'92 vibration

[Tim Scales]

Hello. I am "New" to the CAC but an old experience "vette owner. Happy to find you guys! I currently own a "92 dark Red Metallic Coupe. I bought 'er with 17,000 miles on it in 97. I have over 115,000 miles on 'er now. Since the beginning she has a slight vibration when accelerating from OD Lockup...it is getting a little worse in her older days and has me somewhat concerned.
To get it "over the vibs" I can either ease up on the acceleration, increase the acceleration or just simply "Tap" the brakes and it will stop the vibs. I am inclined to think it has something to do with the "Lock up" torque converter. I don't want to spend a fortune on her but just wondering if anyone has had the same thing happen. I had a '91 L98 that did the same thing and an 86 also but did not keep those 2 as long as the 92. I have hand and visually checked the U-joints and can see no damage and all appear to work rather smoothly for 115K miles. I do have some dry rot on the rear spring "Cushions" or rubber bushings. Could this have made the vibration worse as time went by? I have checked and no one has the cushion set without ordering. I work in Indiana and am only home about once a month so when I am home I have a very hectic schedule. I love the car and don't want to trade 'er in just yet. It is in otherwise excellent shape. 25-26 MPG on road driving 80+ on average. Uses NO OIL! I have changed oil every 3,000 to 3,500 miles since I bought her and use only Mobil 1 10w30. Keep it in showroom condition. 90% of the miles are road miles as I drive as much as 4,000 a month in my job. Please help if you can...Thanks, Tim

[jsinga]

You might have a torque converter/ transmission problem going on. If it's in the transmission it should do it on other gears besides OD. I'm inclined to say any car over 100K miles has worn out half-shaft u-joints. My 200K mile 87 is working on it's second set of half-shaft u-joints. Don't worry about the driveshaft, it doesn't move and those u-joints don't wear out.
You can change half-shaft u-joints in an afternoon at home.

JS

[gearshift]

I had a similar problem and it turned out that the break calipar was sticking due to the ABS systems behind the drivers seat failed. I found a used one for about $200 and had it installed.

[Tim Scales]

Thanks Guys!
I took 'er to the tranny shop to have the pan pulled and while changing the filter and fluid I noticed the pressure valve that someone spoke of in an earlier thread was loose. I had the mechanic remove the valve and inspect it for cracks. No cracks! He put it back in and tightened it down good and guess what? No more VIBES!!!! Thanks for the advice Men! Keep up the good work, Tim