Drivetrain movement (crossmember??)
10-26-2015, 06:07 PM
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Car: 87 T/A
Engine: 400SBC Carb'd
Transmission: T56, Kevlar clutch
Axle/Gears: 3.73 Yukon Duragrip posi
Drivetrain movement (crossmember??)
So, my engine/transmission have always shuddered a lot since my t56 swap. Even with an organic clutch, it still tended to shudder way more than it should.
Just (for other reasons) got a new clutch kit, Kevlar, with new pilot bushing, etc... and it's a lot worse. I had my console out of the car, so I could see the top of the transmission, and that thing bucked up and down a LOT more than it should.
I have one of those "hump" style crossmembers, for exhaust clearance, but it's one of the crappy ones that are just plate steel, no boxing.
http://www.hawksthirdgenparts.com/tr...r-t56-6-speed/
To me, if the transmission is bucking up and down, that means the crossmember is flexing up and down, which it should not do. I'm also considering poly engine mounts (or solid) because I think that's a weak point as well.
Thoughts? This is very frustrating. Especially since everyone says Kevlar clutches are "so smooth"... :/
Just (for other reasons) got a new clutch kit, Kevlar, with new pilot bushing, etc... and it's a lot worse. I had my console out of the car, so I could see the top of the transmission, and that thing bucked up and down a LOT more than it should.
I have one of those "hump" style crossmembers, for exhaust clearance, but it's one of the crappy ones that are just plate steel, no boxing.
http://www.hawksthirdgenparts.com/tr...r-t56-6-speed/
To me, if the transmission is bucking up and down, that means the crossmember is flexing up and down, which it should not do. I'm also considering poly engine mounts (or solid) because I think that's a weak point as well.
Thoughts? This is very frustrating. Especially since everyone says Kevlar clutches are "so smooth"... :/
10-26-2015, 10:49 PM
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Car: 1988 Camaro
Engine: 355, 10.34:1, 249/252 @.050", IK200
Transmission: TH-400, 3500 stall 9.5" converter
Axle/Gears: Ford 9", detroit locker, 3.89 gears
Re: Drivetrain movement (crossmember??)
My 1st thought was trans mount. How is yours? They are known for cracking/breaking. Install a poly one.
Next, look at that crossmember
Next, look at that crossmember
10-27-2015, 07:16 AM
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Car: 87 T/A
Engine: 400SBC Carb'd
Transmission: T56, Kevlar clutch
Axle/Gears: 3.73 Yukon Duragrip posi
Re: Drivetrain movement (crossmember??)
My trans mount is pretty new, and looks fine. I'm pretty sure the stupid crossmember is just flexing up and down. It has no 3 dimensionality to it, so it's VERY weak up and down. It's just a camel-shaped flat piece of steel, so it has no strength up and down.
I'm thinking about welding in a little crossbar, so it can't flex like that.
I'm thinking about welding in a little crossbar, so it can't flex like that.
10-28-2015, 02:19 AM
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Car: 1989 Iroc-Z Camaro
Engine: TBI,5.0
Transmission: Automatic 700R4
Axle/Gears: Eaton Posi,3.42,LPW Ultimate Cover
Re: Drivetrain movement (crossmember??)
You must lift the transmission a little off of the crossmember to see if the trans mount is tore from the rubber to the metal it attaches to. Otherwise it looks fine.
I tried three different poly mounts until I finally found the "Energy Suspension" #3.1108G without using the loading plate and that fit right with no vibration.(Or very little. It’s hard to tell with poly engine mounts.)
It works for me.
The reason I point out that # mount is because guys have a hard time finding the one that works for them. The geometry of the car plays a roll but I think it’s a good starting point.
Welding a bar there should help though.
I tried three different poly mounts until I finally found the "Energy Suspension" #3.1108G without using the loading plate and that fit right with no vibration.(Or very little. It’s hard to tell with poly engine mounts.)
It works for me.
The reason I point out that # mount is because guys have a hard time finding the one that works for them. The geometry of the car plays a roll but I think it’s a good starting point.
Welding a bar there should help though.
Last edited by Ron U.S.M.C.; 10-28-2015 at 02:23 AM.
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