drivetrain wear, jerky when on/off throttle

[TajMan]

I'm trying to diagnose 'worn' drivetrain problem on my '93 Stealth R/T TT with 109K miles. There seems to be drivetrain lash that feels jerky when I'm on/off throttle, like acceleration/deceleration, shifting gears then back into the clutch/throttle, etc.
It just feels like the car has more than 109K miles I suppose.

Car is not stock, it has a 1-piece carbon fiber driveshaft and an RPS Max stage 3 street clutch (apparently) which is stiffer than the stock pedal feel.

When under the car, you can rotate the 1-piece driveshaft by hand and it seems to have more play than it should back and forth before it engages the rear end/wheels or T-case output (compared to what I think a stock car like-new condition should feel like).

Expert opinions? I heard that loose mounts for the rear differential could cause such feelings?
I'm thinking now, maybe worn splines on the clutch disc itself could cause conditions that feel like this?

[KeithMac]

Probably rear diff backlash out of spec (same as mine), also rear diff mounts can give bother.

How old are you engine mounts?, when I replaced mine at 100k the rear mount was in pieces..

[HLxDrummer]

Engine mounts, rear diff mounts, rear diff backlash, play in the transmission/TC, etc.

If you really want to tell you could disconnect the driveshaft from the rear diff, then wiggle the rear diff flange. You should be able to tell if there is a lot of "slack" in there. You could also wiggle the driveshaft back and forth to see if the play is in the trans/TC/output shaft/etc. If you can take off your hood and drive around you should be able to tell how the mounts are. Either that or just pop the hood and try to pull out in first gear with the emergency brake on and have someone watch.

I would like to adjust the backlash on my rear diff but I am worried if I adjust it it will make noise/wear faster since the car has 180K on it. You guys think that is true?

[green-lantern]

I'm trying to diagnose 'worn' drivetrain problem on my '93 Stealth R/T TT with 109K miles. There seems to be drivetrain lash that feels jerky when I'm on/off throttle, like acceleration/deceleration, shifting gears then back into the clutch/throttle, etc.
It just feels like the car has more than 109K miles I suppose.

Car is not stock, it has a 1-piece carbon fiber driveshaft and an RPS Max stage 3 street clutch (apparently) which is stiffer than the stock pedal feel.

When under the car, you can rotate the 1-piece driveshaft by hand and it seems to have more play than it should back and forth before it engages the rear end/wheels or T-case output (compared to what I think a stock car like-new condition should feel like).

Expert opinions? I heard that loose mounts for the rear differential could cause such feelings?
I'm thinking now, maybe worn splines on the clutch disc itself could cause conditions that feel like this?

Hey dood what's up? Haven't seen you post here in a while.

It could be the output shaft and or TC spool.

Also I had that issue before and it was the rivets loosening up in the clutch.

[TajMan]

heeeey buddy! yeah I haven't posted here or done stuff to my stealth for a second, but I'm driving the car again now.
Sorry I had seen initial reply to thread talking of rear diff backlash, then I was gone in Denver last weekend and forgot about checking thread.
I will officially diagnose this drive-train problem eventually, right now I'm just looking for time to install waiting parts and pass emissions, one of my problems is I may need a '93 TT ECU to swap out with mine and test/possibly_fix running issues I'm still having now. I guess nobody in the Utah community here has a '93 TT, unique year ecu..

[Primus101]

Some of your excess drivetrain lash could also be from the dog-style connection between the VCU & the sun gear assembly in the center diff.

[green-lantern]

heeeey buddy! yeah I haven't posted here or done stuff to my stealth for a second, but I'm driving the car again now.
Sorry I had seen initial reply to thread talking of rear diff backlash, then I was gone in Denver last weekend and forgot about checking thread.
I will officially diagnose this drive-train problem eventually, right now I'm just looking for time to install waiting parts and pass emissions, one of my problems is I may need a '93 TT ECU to swap out with mine and test/possibly_fix running issues I'm still having now. I guess nobody in the Utah community here has a '93 TT, unique year ecu..

I have a 92TT ECU, I know it's a little different but I believe it will run OK. I think the timing will just be a bit off.

[TajMan]

That's good to know, maybe someone with a '92 TT locally can actually help me in testing..

[drew0u812]

Some of your excess drivetrain lash could also be from the dog-style connection between the VCU & the sun gear assembly in the center diff.

Yeah, I have seen the holes elongate which just adds to the slop.

[DrGonzo]

I had the same issue. I made letting on/off the gas pedal a pain as it would jerk and clunk every damn time. I checked the backlash on both rear diff's I had swapping them both in/out with no luck. Poly filled the carrier bearings to make them solid, no luck. I pulled the output shaft and transfer case and had the shaft and input spool replaced with Ninja parts. That got rid of the all of the problems I was having. Only took me a year to get it all figured out!!!