vorteciroc

I have set up quite a few 9 Bolt differentials, some of which needed the carrier friction cones machined as per the TGO Technical Article that can be found here: https://www.thirdgen.org/bw_9-bolt_cone_repair

I have had some great luck with this minor machining procedure in lieu of having new parts available for this differential.

However many people here recommended placing an order with 9Bolt.com.

I received a pair of new carrier friction cones:


Upon first inspection, i was very please all dimensions looked identical to the original cones, Until i realized that indeed one dimension was different.


The side of the friction cone that rest against the carrier needs to be countersunk like the original cones.


Note this cone had bottomed out in the carrier and is excessively worn, however notice how in this view the top side of the cone is countersunk outside of the splined area.

Here is a closer look:


Now i need some opinions... Should i machine the new cones to be countersunk like the originals. Or should i machine the carrier it self shown here:


Obviously one or the other needed to be machined or the cone will not seat in the carrier and there will be no limited slip action.

Anyone used these cones? Anyone done this modification to the carrier it self?

Twin_Turbo

iTrader: (25)

You got them from 9 bolt like that? Maybe you got unfinished cones? If that's how they come, I'm not going to buy a set, I'll machine the old ones and shim.

I would machine the carrier and leave more spline area on the cones

big gear head

If you are able to get inside the case and machine it then that is probably the way to go. I don't see how it would make anything weaker by doing it that way.

Twin_Turbo

iTrader: (25)

the case splits in 2 so it's easy to machine that part after clocking it true in the lathe.

big gear head

Yea, that's the part I was wondering about. How are you going to hold it in the lathe? The case is kind of irregular shaped, so I figure it's going to be hard to hold.

Twin_Turbo

iTrader: (25)

If you pull the side bearings off you have a nice true surface to chuck in the lathe.

remember, this thing splits in 2 w/ all the bolts removed.

vorteciroc

With the carrier halves completely disassembled they are very easy to mount on a lathe.


As stated above with the carrier side bearings removed, the carrier halves will mount with no problem.

vorteciroc

Some here by now must have purchased new cones...

Maybe?

Anyone...?

vorteciroc

Thank you for your input guys.

I was hoping for some more opinions though...

I have quite a few spares for the 9 bolt in my car, so this is what i decided to do earlier tonight.



I decided to turn the inside of the carrier halves for necessary clearance to use the new carrier friction cones on my lathe. I simply removed the raised area inside the carrier halves and made that area flush with the lowest point there.

Here is a comparison of the before and after...


Vs


I also removed 1mm from the smaller end of the new carrier friction cones for added clearance/ longer cone life.


What is also a benefit is that the new cones have a thicker splined center and hopefully will be stronger than the old set of cones.


Vs


Now, what the cones look like worn/ bottomed out the the carrier...


Now with the new cones, notice the window in the side of the carrier half is now open...

80malibu-175

can any1 answer a couple questions for me? I am about to pull my hair out!!!! please!!!

vorteciroc

What are your questions?

80malibu-175

I put a set of alum heads on my 355 and now when I went to put the intake back on there is a gap where the intake runners overlap the intake manifold. It is a very small gap. Like only a 16th inch but that will never work. Its a performer rpm high rise. Any Idea how I might fix that problem without having to buy a new intake?

80malibu-175

I will buy one if it comes to that, and I really dont see any other way of fixing it.

Twin_Turbo

iTrader: (25)

what does that have to do w/ a 9 bolt axle?

Your heads are angle milled, need to correct intake for that.

eagle_eyes

iTrader: (3)

thanks for this info. i'm assuming the posi works correctly doing it this way?
i ran into the same problem...the new cones i ordered do not have countersunk ends on them. I'm going to do what you did and machine the carrier halfs to get them to work.

dimented24x7

iTrader: (2)

I take it the new cones are only available for the 3-series carriers?

dimented24x7

iTrader: (2)

NVM my last post. I was having a brain fart. I tried contacting them, but the email got bounced twice with no reply. Theyre still up and going, right? I want to grab a set of these to fix my rear. Seems like it might be a better option than trying to cobble together something with the exising worn parts.

irocz

so what's the verdict on the 9bolt.com cones? suck or not?

IAGTA

I just ordered a set on Monday and I will report back on what they look like. This has been a great post and very informative.

IAGTA

Finally received my new cones and they look exactly like the cones pictured above - so I guess machining of the posi housing is now required when new cones are installed.

Twin_Turbo

iTrader: (25)

I just noticed something after looking at this thread again, the new cones have the grooves running the other directions compared to the originals..., wtf?