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Driveline Grinding - NEWBeee on here

REBS-TA

Active Member
Hey guys. I just bought a rough '89 TTA a few weeks back and although not abused it was not loved. So, going through it front to back. So far replaced; waterpump, heater core, plug wires, motor mounts, trans mount, u-joints, window tint and tires... I've been restoring old muscle cars for years and have had at least a dozen 3rd Gen TA(s), but this is my first '89 Turbo TA (always wanted one). Also the first one that's had this problem.

I've got a driveline problem: Under acceleration (light or heavy), there is a constant grinding/vibration. Vibrates the car and my belly. Almost like running over a cobblestone road. If you have ever had an exhaust system on a race car get within a 1/8" of the floor pan and it start vibrating under acceleration, you know what I'm talking about. The differance is this is in the driveline..feels like a worn out bear or bearing somewhere. Doesn't matter what gear or what speed. With no acceleration, it's still there, just not as intense. The tires were old, so I replaced them, already did the u-joints..no real change. So, before I start tearing into the rear-end or tranny...would like to hear from folks that's been there done that. Car has 75k miles. Rebuilding the rear doesn't sound like much on this car with the lack of parts available for the BW 9 bolt. Don't want to tear into the tranny, as it appears to be shifting fine, but who knows, maybe the output shaft gears or bearings have gone bad.. I'm just too new to the 200r and 9 bolt set up to know what to look for.

Thanks guys and any help would be appreciated.
 
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I have had that before and I thought the transmission was going to explode. It ended up being a bad plug. It is any easy check and is worth trying. Did it do it before you replaced the plugs and wires? If not, recheck them and make sure you didn't cross a wire. Just my 2 cents since that got me once. I hope it is something simple like this, also you can check your flex plate bolts, maybe they are loose.
 
Thanks Mike,

I corrected the work already done. We didn't change the plugs, they looked good, just the plug wires. Will do that this weekend. It would shock the crap out of a group of us looking at this thing to see that work, but we would certainly be happy campers. Both rear wheels were severely wharped (I would expect some vibration from there, but I would expect it to be constant and not exaggerated when under load/acceleration). The wheels go to the "Just Fix it Wheel Place"..today.
The guys at the shop still are putting money on the rear. After researching the web for parts/rebuild kits, I'm praying it's not. Only used 3.42 ring and pinions available and only used carriers...then another $300+ for the complete rebuild kit.. wow... I'm loving my old 10&12 bolt rear ends more and more. Parts are a sure lot easy to get.
 
Would still like to hear from others experience. I will keep reporting back. I am trying to bring this baby back to life. Needs a lot of TLC. After I get her restored, I'll be looking for a low mileage show car, one year from now is the target.
 
I wouldn't totally rule out the flexplate, but when it's loose it makes more of a clanging noise like the downpipe hitting the frame. Under acceleration the centrifugal force would push the flexplate in one direction and the noise would go away. The only time you'd hear the noise would be under deceleration or idle.

But with that said it's easy enough to remove the inspection cover and check it out.

Don't ask me how I know this. :bash:
 
Flex plate tight, changed plugs, next takking the drive shaft to the balance shop...however, it doesn't look to have any issues, dents or physical damage to cause it to go out. We also put the car up on the lift and spun it up. No appearant vibration from the shaft..but I do understand harmonics and mechanics and looks can be deceiving. Vibration and noise really sounds like it is coming from the rear end. Occurs in forward and reverse... also a pretty major clunk when put into either reverse or forward and the slack gets taken out. Looking at the rear on e-bay and 3rd gen forums. This is getting expensive, quick.

Thanks for your help guys...
 
Hopefully will find out during the Christmas holidays. Will have some time off and start tearing in to the rear. Throught if it was the pinion bearing there would be some play with putting pressure on the yolk..but, then again, I don't know these rear ends, but I will soon enough. I'll probably replace all the bearing and seals and just get the entire rebuild kit and pray the ring/pinion aren't damaged and also the carrier is still good.

thanks..Robby
 
Just wanted to update the thread. After replacing the u-joints, balancing the drive shaft, checking the flex plate bolts, replacing pulgs and pulg wires, replacing then reinstalling coil pack, replacing tires, having the rims restored to new....I replaced the torque converter...That was it...
 
I am glad you found it. A damn shame I did not see your post earlier. I was going to say that I had a tta do that and it was the torque converter bolts being loose. Very frustrating and it went on for a year before anyone figured it out. Someone had probably forgotten to tighten them when they put the car back together from their racing project.
 
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