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I'm digging into my A/C delete, removing the condenser, and currently have the best access I'm going to get to this aftermarket trans cooler:
It's attached via two zipties to the body and a pair of three foot long rubber lines clamped to hacked off hardlines under the car. It leaks at that connection and I'd like to redo this whole situation. What would be the best way to incorporate the factory trans cooler in the radiator and this one together?
Would the ziptie style through straps work to mount it directly to the rad with my stock twin electric fans, or should I make brackets? Can I feed trans fluid into the bottom of the radiator cooler, output fluid from the top into the top of the aux cooler, and then return from the bottom of the aux cooler to the trans? Or should I always go from top to bottom?
Do I need to do it all with hard lines, or is there some trick AN stuff I could buy to make some nice flexible lines? How would you redo this setup?
Please share your tips and advice with me. Thanks!
I would skip the radiator and just use the aftermarket. The hot radiator was never very effective at cooling transmission fluid, plus cross leaking fluids can quickly damage your transmission before you even know it's happening.
I would NOT use the zip ties to attach it anywhere, especially the radiator. Zip ties get brittle and break after a few years, and running zip ties through your radiator is inviting a future leak and just begging to permanently destroy our radiator.
Do it the right way. Fabricate some brackets for the aftermarket. Braided AN lines are best way to go, but hydraulic hose and worm gear clamps can last a very long time and are much easier. Make sure the hose is routed such to not get rubbed raw anywhere.
Definitely following along on this as if I swap to a higher stall converter I will need a secondary cooler, likely one of the tru cool units.
I would run mine to work through the radiator first and then at the radiator return ( bottom line below lower rad hose) to secondary cooler and back to the trans return. As far as mounting goes I agree with Aaron R to fab something and avoid the direct contact to radiator or AC condenser. Although a lot of ppl do it and it seems to work I would worry about damaging the radiator over time and the fact you loose a lot of cooling efficiency if it’s right on the radiator.
Also I would use Corbin clamps on the cooler so you don’t have to worry about the worm gear type getting loose. Other ppl have used fuel injector clamps on the return line and radiator connections if you do rubber lines for extra grip.
Transmission fluid needs to reach a certain temp before it works properly. Keeping it "too cool" is as bad as letting it get too hot.
Optimum temp is something in the 165 - 185° neighborhood.
The cooler in the rad is EXTREMELY efficient, as is any fluid-to-fluid heat exchanger. MUCH more efficient than a fluid-to-air exchanger. The trans fluid running through it comes back out at the temp of the cold side of the engine cooling system; ideally, a few degrees (exactly how many, depends on the ambient temp) below the engine thermostat temp. Usually, this is just fine; the cooler is large enough, and the engine coolant system's cold side temp low enough, that the trans fluid temp is in the right range. However, if the ambient temp is very high (let's say, much over 95° or so in most situations), or the AC is on which heats up the air passing through the rad, or an unusual amount of heat is being dumped into the trans fluid such as by a "slipping" torque converter or other "abuse", then the factory cooler may not be enough. That's what your add-on cooler needs to address; NOT "the factory one is crap, eliminate it".
Best solution is a system where the hot fluid exits the transmission and goes to the factory cooler; then goes to an extra cooler with a thermostatic bypass; then returns to the trans. Many coolers specifically for trans fluid have this built in, but a "general purpose" one of course does not, since it might be installed to cool engine oil, PS fluid, etc., whose temp requirements are different.
The trans cooler mfrs, and others, make thermostatic bypass valves to deal with this. For example https://www.improvedracing.com/oil-t...ermostats.html When the trans fluid temp is below [whatever], they bypass the cooler, then route the fluid through the cooler when it's above the set point. Interestingly enough, the people who make these, usually set them at 185° for trans fluid.
If it was me, I'd avoid ANY kind of rubber hose, and ABOVE ALL, worm-gear clamps. That combination ALWAYS leaks, ALWAYS, EVERY TIME. Not much sense in deliberately installing leaks in your system.
I'd suggest instead, a cooler that either has fittings already that you can set up for either AN hose or hydraulic hose adapters, with some kind of retention method for the hose OTHER THAN worm-gear clamps, and mounting the cooler somewhere that has good air flow, but other than in front of the AC and radiator, if possible. Not sure where that might be, and may not be possible, but I'd try to find such a place if I could. Below the battery, or the similar place on the other side, might be something that would work. I would use clamps to hold the lines to something secure rather using than tie-wraps.
I'd also recommend against deleting the AC, unless this is going to be a track-only car. There's little sense in taking a potentially "nice" car and relegating it to the usual dusty, grimy, BO-filled mess that cars without AC usually turn into. But that's just me; I can't stand being in a car like that. I like mine clean and comfortable. You may feel differently. Especially since our cars don't have floor vents like older non-AC cars used to come with, they tend to get unbearably hot from the lack of adequate ventilation. Butt hay, that's your choice to make, do as you please.
Last edited by sofakingdom; 02-12-2022 at 10:01 AM.
Transmission fluid needs to reach a certain temp before it works properly. Keeping it "too cool" is as bad as letting it get too hot.
There are a lot of dumb things posted on these forums, and I have probably been guilty of the same, but this is the dumbest I have seen lately.
Who knew that your transmission doesn't work properly until the car is completely warmed up. Now if you are reading this I can imagine what you are thinking: "but just yesterday I started my car and drove to work in 0* weather and the engine (and radiator/transmission) never got warm, but it worked fine the whole time", or even "but wait, my car shifts the same cold as it does warm". Silly people, everyone knows your transmission won't work until you have driven it for a while. The transmission fluid must be hot (185* fluid is extremely hot).
I always let my cars warm up for at least an hour before I drive them. Transmission fluid won't "work properly" unless I do that. Sometimes in the coldest parts of winter I leave them running 24/7, just to make sure my fluid "works properly".
and mounting the cooler somewhere that has good air flow, but other than in front of the AC and radiator, if possible. Not sure where that might be, and may not be possible, but I'd try to find such a place if I could.
This is excellent advice. Definitely dont mount something you want cooled in front of the radiator. Car manufacturers have been doing that for decades and for some reason have been designing the front of cars to facilitate air flow through the radiator area, but this is a huge mistake. Mount it somewhere else. Not sure where because myself and nobody else I know has never done that, but here are some ideas to help you:
-Under the front of the car. Lots of air flow here, and the only down side is you will be replacing the cooler every week as rocks punch holes in it.
-In the trunk. Very safe place, just gotta figure out how to get air flowing through there. Maybe permanently remove the back hatch glass.
-On a tow behind trailer. This is a novel approach, but worth considering. Have the local UHaul install a hitch on your Camaro and tow a small trailer everywhere. You can mount the oil cooler on it along with some large fans.
-Directly on the windshield. This is my favorite. Lots of airflow here, plus you can keep a close eye on it to watch for leaks from the worm gear clamps. Dont worry, no State has any laws about driving with an obstructed windshield.
Best solution is a system where the hot fluid exits the transmission and goes to the factory cooler; then goes to an extra cooler with a thermostatic bypass; then returns to the trans. Many coolers specifically for trans fluid have this built in, but a "general purpose" one of course does not, since it might be installed to cool engine oil, PS fluid, etc., whose temp requirements are different.
The trans cooler mfrs, and others, make thermostatic bypass valves to deal with this. For example https://www.improvedracing.com/oil-t...ermostats.html When the trans fluid temp is below [whatever], they bypass the cooler, then route the fluid through the cooler when it's above the set point. Interestingly enough, the people who make these, usually set them at 185° for trans fluid.
That makes sense, I've been looking at this thermostatic bypass mainly because it's substantially cheaper:
I did a bunch of reading last night to come up with a proposed cooling system:
Bottom line from trans (feed) -> Bottom fitting in radiator cooler (fill from bottom to prevent aeration) -> Top fitting in rad cooler to IN on thermostat -> OUT on thermostat back to top line on trans (return). Obviously the second pair of out/in on the thermostat goes to the cooler, which will also be filled from the bottom unless both in/outs are on top.
I'm also going to try and flare my hacked off lines on the car and stick a hardline union on them, because I'm lazy and don't want to roll around in the gravel trying to get the fittings off at the trans.
Originally Posted by sofakingdom
If it was me, I'd avoid ANY kind of rubber hose, and ABOVE ALL, worm-gear clamps. That combination ALWAYS leaks, ALWAYS, EVERY TIME. Not much sense in deliberately installing leaks in your system.
I'd suggest instead, a cooler that either has fittings already that you can set up for either AN hose or hydraulic hose adapters, with some kind of retention method for the hose OTHER THAN worm-gear clamps, and mounting the cooler somewhere that has good air flow, but other than in front of the AC and radiator, if possible. Not sure where that might be, and may not be possible, but I'd try to find such a place if I could. Below the battery, or the similar place on the other side, might be something that would work. I would use clamps to hold the lines to something secure rather using than tie-wraps.
I'll have to see if I can adapt some different fittings to the cooler I have. Not that I'm necessarily married to this one, but might as well see if this is going to do what I want it to do. Or, do it well enough for now until I go back in for a better setup. This particular cooler is a bit wide and thin, I think I'd be looking at moving some metal around to get it parked anywhere but in front of the rad. If I were very motivated and really wanted to throw down some cash on this, I like the idea of turning the turn signals back into the vents they always wanted to be, and then ducting that into the isolated cooler(s):
I'd also recommend against deleting the AC, unless this is going to be a track-only car. There's little sense in taking a potentially "nice" car and relegating it to the usual dusty, grimy, BO-filled mess that cars without AC usually turn into. But that's just me; I can't stand being in a car like that. I like mine clean and comfortable. You may feel differently. Especially since our cars don't have floor vents like older non-AC cars used to come with, they tend to get unbearably hot from the lack of adequate ventilation. Butt hay, that's your choice to make, do as you please.
I agree, A/C will be going back in at a later date when I hit that level of priority in my project list. I got the delete pulley as a 'for now' solution because the whole system has been inoperative / dry for 11+ years. The compressor is junk, everything is contaminated with dirty old oil, the hoses are severely cracked, so it's all gotta come out for cleaning and evaluation.
Originally Posted by Aaron R.
I always let my cars warm up for at least an hour before I drive them. Transmission fluid won't "work properly" unless I do that. Sometimes in the coldest parts of winter I leave them running 24/7, just to make sure my fluid "works properly".
You know there are placed in the world that are so cold that people do actually run cars 24/7? Do you also go WOT regularly before your thermostat opens? Fluid that is too cold is at the wrong viscosity, and that might affect its ability to lubricate the system as intended. There is no downside to achieving and maintaining a happy operating temperature as quickly as possible.
Originally Posted by Aaron R.
This is excellent advice. Definitely dont mount something you want cooled in front of the radiator. Car manufacturers have been doing that for decades and for some reason have been designing the front of cars to facilitate air flow through the radiator area, but this is a huge mistake. Mount it somewhere else. Not sure where because myself and nobody else I know has never done that, but here are some ideas to help you:
Guess you don't know a lot of people, plenty of actual alternative solutions here:
I might end up installing the trans cooler in front of the rad for now out of convenience and since my car is actually bone stock, I'm no where near the limits of compromising anything. But, I specified the best. How many race cars do you see with stacked coolers? Obviously you want maximum airflow directly to the rad with no obstructions in an ideal arrangement. Not to mention two of your nonsensical solutions are actually viable with wire to block rocks / a fan attached to the cooler.
I'm also going to try and flare my hacked off lines on the car and stick a hardline union on them, because I'm lazy and don't want to roll around in the gravel trying to get the fittings off at the trans.I'll have to see if I can adapt some different fittings to the cooler I have.
You came to a forum asking for advice, are proposing some very complicated solutions to a simple problem, then said this above....
You need to step back and evaluate yourself and your actual potential. This poor third gen is headed toward the slow painful demise of so many already crushed. If you are admittedly too lazy to even remove some existing lines from your transmission you probably are not ready for a fabrication project. Think about it.
Also, keep in mind every new connection you create (like your hardline union idea) is a potential future leak point. Too proud to use a worm gear clamp but happy to create another joint and potential leak. Dude, keep it simple. Review that other thirdgen forum thread you linked. Full of people with very complicated solutions to a very simple problem, some of whom even admitted later in that thread it didnt work out so well for them.
Most of the third gens that deteriorated and fell apart in someone's yard died from owners just like this. Cool ideas but too lazy to fix a hard line, or deleting their a/c while making plans to reinstall it later . Grand schemes so complicated nothing ever happened and the car slowly rotted away until the crusher arrived for its final road trip to the scrapyard. But hey, to each their own. I've already saved two from owners who were like this, maybe yours will be my third.
I dunno what the tiny / bars that make an X do, but I removed mine and used the holes and installed some painted metal horizontal bars bars to mount the cooler maybe 1 - 2 inches away from the condenser. Just thick enough to mount securely yet not hinder air flow.... and i used the other side to install an auxillary pusher fan and power steering cooler.
Routed the trans fluid to go into the rad cooler, stock I think it goes, top down, then from the bottom fitting to the cooler then back to the trans. So far no issues!
I dunno what the tiny / bars that make an X do, but I removed mine and used the holes and installed some painted metal horizontal bars bars to mount the cooler maybe 1 - 2 inches away from the condenser. Just thick enough to mount securely yet not hinder air flow.... and i used the other side to install an auxillary pusher fan and power steering cooler.
Routed the trans fluid to go into the rad cooler, stock I think it goes, top down, then from the bottom fitting to the cooler then back to the trans. So far no issues!
What size cooler did you run? I've been looking at the tru cool 4588 ( LPD4588 24 5 3/4 x 11 x 1 1/2 19.000 GVD 14.400 BTU 11/32 hose barb) but its hard to gauge which size would be best for our cars. It seems the LPD model I referenced is the same as the B&M 70264 that seems popular on here. The big difference is the tru cool has a lifetime warranty and costs a little less. What is nice with the LPD series is I believe they will not let the trans fluid run too cool because as they have a cold weather bypass.
Last edited by Reddragon88gta; 02-14-2022 at 04:07 PM.
What size cooler did you run? I've been looking at the tru cool 4588 ( LPD4588 24 5 3/4 x 11 x 1 1/2 19.000 GVD 14.400 BTU 11/32 hose barb) but its hard to gauge which size would be best for our cars. It seems the LPD model I referenced is the same as the B&M 70264 that seems popular on here. The big difference is the tru cool has a lifetime warranty and costs a little less. What is nice with the LPD series is I believe they will not let the trans fluid run too cool because as they have a cold weather bypass.
I used a Hayden Automotive 677 Rapid-Cool Plate and Fin Transmission Cooler. Size is 3/4 inch x 11 inch x 7-1/2 inch Its on sale for like $35 on amazon now!
I found this to be a good size based on the space up in there.
I DO live in Hawaii though so overcooling etc.. prolly isn;t an issue here!
I just noticed...thats a pretty massive cooler you got.
Do you need one that large?
Probably not, but it's there and someday I'd like to install a higher stall converter so trans temps is a future problem that I'm addressing now because I've got it all apart.
This is sorta what I'm thinking in terms of placement:
Orange line is feed from trans.
Red line is exit from stock cooler into IN on thermostatic bypass.
Magenta lines are to and from cooler. For the sake of simplicity, I think I'm going to mount it in front of the rad. Does distance matter here? Should I duct any / all of the coolers? There was some thick foam between the condenser and rad, but I'm not sure if I need to replace it without the condenser there.
Yellow box is the proposed location of the bypass. Will probably relocate the primary fan relay forward a little but it seems like I can pass the cooler lines through the sheetmetal there with some grommetted holes and some 90 degree fittings. My concern here is that there will be a ton of line connections here after the condenser goes back in and I won't actually be able to rotate a wrench to snug up the hardlines, but we can burn that bridge when we cross it. Might just need to disconnect the fittings at the bypass first whenever condenser is disconnected, which is hopefully infrequent.
Blue is return to trans.
Still trying to decide if I want to go hardlines with 5/16 inverted flare connectors, or braided hose with AN fittings. Seems like the cost ends up being about the same.
Magenta lines are to and from cooler. For the sake of simplicity, I think I'm going to mount it in front of the rad. Does distance matter here? Should I duct any / all of the coolers? There was some thick foam between the condenser and rad, but I'm not sure if I need to replace it without the condenser there.
I am no expert but I would re-use or get new foam pieces if you mount to the radiator to be safe. From what I have read that little bit of distance helps to not create a hot spot and get a little more air to help cool. But tru cool also states that using an aux cooler should lower system temps as there is less load and will not increase engine operating temps when asked about placement in front of the radiator.
I think you have a solid plan, I would check for a part # on your current cooler, it might already have the thermostatic bypass as some cone with them.
But maybe you should consider going with a cooler with the thermo valve already integrated?
That space there where your thermo valve is, is kinda tight.... and with the ac condenser lines, the rad pushed more forward etc... it might get crowded. Its hard enough to get regular trans hose around that area from the rad to a cooler.....
Also......... looks like you got the wiring for dual fans??....go with LS1 fans while youre in there!!
FWIW, I added a B&W 70273 cooler after upgrading the converter. Sorry, pics aren't very good, but I plumbed AN fittings to the top radiator transmission cooling line.
This cooler matches the exact description of the LPD4454. It's got 36 plates, it's exactly 7 1/4 x 11 x 3/4, and 11/32 would be the correct barb size available to match up with a 5/16 hardline. It also looks just like the one in the older box picture here. So, I think it's a Tru-Cool LPD, which is great because that means it does already have the bypass.
The barbs are fixed, so I'll have to use hoses and clamps for that connection, but since I don't need an external bypass, I'm now thinking about running the new lines directly to bulkhead fittings underneath the primary fan relay. I'll just run short rubber hoses from there to the cooler and they won't need to do any serious bends.
Looks like there's some relatively easy places to make brackets below the cooler. Considering tying into the cross bars in some fashion for the top bracket, not as good of places for brackets above.
This cooler matches the exact description of the LPD4454. It's got 36 plates, it's exactly 7 1/4 x 11 x 3/4, and 11/32 would be the correct barb size available to match up with a 5/16 hardline. It also looks just like the one in the older box picture here. So, I think it's a Tru-Cool LPD, which is great because that means it does already have the bypass.
The barbs are fixed, so I'll have to use hoses and clamps for that connection, but since I don't need an external bypass, I'm now thinking about running the new lines directly to bulkhead fittings underneath the primary fan relay. I'll just run short rubber hoses from there to the cooler and they won't need to do any serious bends.
Looks like there's some relatively easy places to make brackets below the cooler. Considering tying into the cross bars in some fashion for the top bracket, not as good of places for brackets above.
In theory, you could also put it horizontal to the ground in front of where the condenser / radiator are... these cars suck air from the bottom and if you put the air dam in place can have air be pushed up right through it before it goes into the condenser / rad for maximum cooling.
Then again one may argue that if it itsn;t against the radiator, air will push around rather than through etc.............
Progress update, I'm considering this a first functional mockup of the best idea I've had so far. I decided to try a non-destructive approach to attach it to the car, so I've got three cable clamps to get bolt holes on the cross bars, with one direct connection that reuses the factory bolt that secures the front bits together. Mostly stuff found in the home depot electrical section. I will probably swap out the hardware for hex head bolts once I finalize sizes and lengths. It's surprisingly secure even without the clamps fastened.
I had to flip the cooler around so the flat side is facing towards the front of the car. Looking through the cooler, it doesn't appear to be directional so I think that should be ok.
I think you wil lhave ery little wiggle room for a condenser though. theres maybe a small gap between where the condenser site and where your cooler bottom sits.
Cooler is too small for a stand alone cooler. Needs to have the radiator cooler plumbed in ahead of it. There is a massive difference in cooling capacity with the radiator cooler in the loop.
Cooler is too small for a stand alone cooler. Needs to have the radiator cooler plumbed in ahead of it. There is a massive difference in cooling capacity with the radiator cooler in the loop.
Agreed, I'm doing both in that order. I think the previous owner came up with this idea to get heat out of the rad to "fix the overheating", all the while running the car without a lower air dam .
Feed lines into both coolers are going in from the bottom ports to fight aeration, and I'm adapting my hard lines to AN where they've been cut and running custom lengths. I got a pair of bulkhead fittings to pass them through the stock holes on the body, depending on fitment with the condenser.
I went with the absolute cheapest AN equipment on ebay. Clearly nothing could go wrong here.
It fits with the condenser! 1989karr you were right, it's very tight on the bottom.
I might try to get it to sit up a little higher, but I didn't have to fight the condenser at all so I don't think they're touching. The cooler is very secure with everything clamped down, the cross braces start moving before the cooler does when I tugged on it. My idea to use the factory holes for the bulkhead fittings probably isn't going to work:
But, there does appear to be enough room available to still use that area with a new hole for the feed into the cooler. Still deciding on how to pass the return back to the trans, there are a few possible routes since the line can travel lower in the bay.
I ended up ovaling out that upper hole a little too give the feed line just a little more space, but it sneaks behind the condenser just fine. I'll need to put a gap in the sealing foam strip to let it pass through but that's no big deal. Looks like I can mount the primary fan relay using the middle hole on the bracket to the left hole in the factory spot, and the 90 AN fitting sneaks right around it:
I tried to go for the easiest bends I could get:
For the return, I decided to go through the plastic ducting, which will point another 90 AN fitting directly back across the frame rail. The idea is to sneak up into the engine bay, overtop the wonderbar and sway bar, and hook right back into the return hardline:
Nothing is clamped down yet, just loosely fitted. Check out the brutally broken tow hook. This car has seen some interesting stuff.
Jow wil lservicing be once everything is in place? I mean like if some line leaks or breaks.. .are they easy to get to with the rad / condenser etc.. in place?
Jow wil lservicing be once everything is in place? I mean like if some line leaks or breaks.. .are they easy to get to with the rad / condenser etc.. in place?
It's possible to reach the hoses from underneath the car since it's all forward from the condenser. You make a good point about accessing the screws on the clamps, I'll turn them around so I can get them all from underneath. The feed bulkhead connection is tight but can be accessed from the top. Worst case a new hose could be fed up from the bottom through the foam gap. If the cooler itself fails, that would require condenser removal.
I finally have all the pieces together and somewhat finalized. Trans cooler hardware is all locked down with stainless and nylock nuts. The rubber trans cooler line has the perfect ID to wrap around the cross bars, I used discarded hose end bits as vibration isolators where the cooler might touch and locked them into position on the bars with zip ties. I also jammed one of the original cooler pads with some fresh double sided tape between the center frame support rail and the cooler. It doesn't make any noise or move at all when I jiggle it so I think it's good.
Flared what's left of my hard lines on the car. It wasn't easy, but I think my result is acceptable:
Here's what the beginning and end AN lines look like. Hopefully the double adapter won't bite me, doing it this way saved me $30 in fitting costs. I'm thinking about tying the two lines together, and the slight residual tension between the two lines will keep them centered between everything once it gets busier in this area.
This is the intermediate line, radiator cooler out to aux cooler in.
And this is the other end of the return to trans line under the frame rail.
Will it leak? No idea, lol. Picked up some 1"x1" expanding weatherstrip foam at the hardware store today. I figure I can double or triple up on it and fill the gap between the rad and the front of the bay.
Update: it works! I got everything back together today and after tightening down 3 minor leaks (both flare nuts into the brass union, and a softline to bulkhead connection), I have a leak free setup. I guess we'll have to see if these cheap fittings stay that way but so far, so good. Here's some pics of the final orientation:
Weatherstrip foam, 3x 15 or so inches on each side. I guess I could have filled the gap at the top as well by making them longer but this should duct as well as oem I reckon.
Ended up using the 45 to sneak around the lower rad hose:
45 feed into the rad, holds up lower hose with zip tie:
Everything hangs nicely and doesn't rub:
Final hardware for cooler, as viewed from underneath the bumper:
Trans fluid for our typical units (4l80e, 4l60e, th350, similar) should stay 155 to 165*F in the pan, according to many sources including my own experience
We like to see 160 in our shop, but do not run it cooler than 50 degree's cooler than your motor temp.
Discussion
If you run the trans at 165*, then make a WOT Pass, or spirited driving, it will rise from there gradually in the pan even with substantial cooling aux exterior components.
Thus it will approach 175*F- the maximum desired temperature of transmission fluid.
This is why we avoid running the transmission at 175*F steady- it will rise to 180+ easily from 175.
Engine coolant runs hotter
Engine coolant should run 195-215*F for most cars, including turbocharged gasoline performance engines.
The outlet temp of coolant from the engine should approach 212*F IMO.
Low coolant temperature is associated with accelerated wear/tear, always thermostat the coolant flow to achieve operating temps rapidly.
Low transmission temp on the other hand does not seem to negatively correlate with increased wear. The fluid viscosity seems to change very little from cold to hot, unlike oil which dramatically changes. The wear properties of clutches (frictions) of a transmission seem not to care what the temperature of the fluid is, as long as it is cooler than 175*F. I don't see any issue running without a transmission thermostat.
I agree with bypassing and avoid the radiator as a transmission cooler because of the large disparity between temperatures and the chance of cross leaking.
I feel the trans cooler should be placed away from the engine radiator and also the transmission cooler should use a fan to regulate temperature for performance setups which produce significant heating such as high stall converters.
Very good thread here and lots of valid points. So let’s pick some brains. Komet, you went from the trans to the bottom of the radiator to deal with aeration. That makes sense. But I was told to go hot to the top, and cool out the bottom. Same with the auxiliary cooler. Because heat rises, so the bottom of the coolers will be a little cooler than the tops. Just slightly, but little bits do matter. And aeration shouldn’t be a problem because any air in that system “should” be flushed out and back into the trans where it is vented through that little vent neck at the top of the trans. I’m not absolutely certain of this so I’d like to hear from some of the ones with more knowledge.
Just a quick note on ATF temperature (applies to Dexron/ Mercon Fluids specifically... Dexron VI as well).
I personally find ideal Temps to be in the 165*F to 185*F range, when measured via the Oil Pan.
I have never seen any harm come from lower Temps...
However Transmission performance would be better in the above Temp range (exceptions when using non-traditional Friction Materials).
Very good thread here and lots of valid points. So let’s pick some brains. Komet, you went from the trans to the bottom of the radiator to deal with aeration. That makes sense. But I was told to go hot to the top, and cool out the bottom. Same with the auxiliary cooler. Because heat rises, so the bottom of the coolers will be a little cooler than the tops. Just slightly, but little bits do matter. And aeration shouldn’t be a problem because any air in that system “should” be flushed out and back into the trans where it is vented through that little vent neck at the top of the trans. I’m not absolutely certain of this so I’d like to hear from some of the ones with more knowledge.
Factory, they squirt from the top of the radiator cooler. ...at least mine does. for 2 birds and my S-10. and it goes down and exits the bottom of the radiator cooler.
I heard about that too about aeration....... I can;t imagine that any air would get stuck though given the force that the fluid is pumped through the lines.
I've run auxillary coolers with the fluid entering numerous ways, top down, bottom up, sideways..... in different makes and models of cars and have never had any problems...... I usually run it so I can pop the line and have fluid pumped out for trans flushes........but i just do normal regular driving so im not sure if that would have any affect on how it flows
02-12-2022, 12:18 AM
I agree, A/C will be going back in at a later date when I hit that level of priority in my project list. I got the delete pulley as a 'for now' solution because the whole system has been inoperative / dry for 11+ years. The compressor is junk, everything is contaminated with dirty old oil, the hoses are severely cracked, so it's all gotta come out for cleaning and evaluation.
. Grand schemes so complicated nothing ever happened and the car slowly rotted away until the crusher arrived for its final road trip to the scrapyard. But hey, to each their own. I've already saved two from owners who were like this, maybe yours will be my third. 
14.400 BTU 11/32 hose barb) but its hard to gauge which size would be best for our cars. It seems the LPD model I referenced is the same as the B&M 70264 that seems popular on here. The big difference is the tru cool has a lifetime warranty and costs a little less. What is nice with the LPD series is I believe they will not let the trans fluid run too cool because as they have a cold weather bypass.
