I"m fighting a vibration for the second year now with no luck. I get a very controlled, almost harmonic, vibration in all gears (auto) and over 70 it gets very strong and about 90 the car feels like it's going to grenade. the feeling is comes then goes comes then goes comes then goes, and the faster you go the fast it comes then goes. (if that makes sense) tires, driveshaft, have both been double checked. one thing i've noticed is if I ride the brakes while still giving it gas at 70+ it controls the vibration to almost nothing, or at least just high speed vibration, vs. a very harsh whooshing vibration. I've rotated the torque converter (and this is the second torque converter) with no luck. any shots in the dark appreciated-

 

Tires?
If they've sat a while you get flat spots that cause this. I was a dummy and the tires I have on my TA have flat spots and are doing exactly as you are describing.

Balancing?
Feeling it in the steering wheel?

 

tires seems good, the car sits 6 months of the year in the garage. they are about 4 years old with about 50% tread left. last year (about early june) was the last time I drove it with the stock motor,tranny and rear end and I don't remember it doing that. so I feel it's one of my componenets I put in??? I did have the wheels doubled checked for balance but no change. I do not feel anything in the steering at all. how did you know the tires had a flat spot? did you get new ones and it was gone? i'll check that, i'll try anything at this point. any other options?

 

could be a bearing problem...and i know you said you've checked it but if your still running the stock driveshaft they are well known for creating vibrations...other then that id say tires...try inflating them up little pass there usual point of course dont go over max psi...then let it sit for a lil while and let air back down to desired psi might work out the flat spots a little...

 

thanks- I'll try that, I have the old stock tires and rims still in the garage, Might not hurt switching the rears and seeing what happens. driveshaft is new with everything else, i had it balanced twice to make sure it's good. bearings- everything should be new, now I know that doesn't mean I didn't get a bad one, but it started right away when I first took the car out after getting it back together. keep the ideas coming, i'll keep testing. thanks

 

Something to ponder...

I too had a vibration. For the life of me, I never could trace it down. Finally, I had the rear end totally rebuilt by a professional. It turned out the bearing race for the pinion was egg shaped. Don't ask me how this happened. Because I haven't the foggiest.

 

not that its not possible but the rear end was brand new complete unit already assembled (excpet for axels straight from moser, I've since (after 800 miles) drained fluid, which looked fine. so that's kinda my problem too, motor, tryanny, rearend are all new so I don't knwo what to suspect. I think i need to find a sharpe mechanic and see what they think. but keep the idea rolling, I appreciate any avenues.

 

one thing I was thinking about is that the vibration is rpm sensitive and not speed sensitive?? what I mean by that is if I'm in third gear (auto) doing 70 the whooshing/vibration is very very strong, once I shift into overdrive it gets better until the rpms reach the same range (about 4000) meaning now i'm doing about 90 in overdrive. so would that rule out tires, ect.???

 

Drive shaft out of balance?

 

brand new driveshaft, and I've had it balanced twice to ensure this wasn't the cause, unless the guys at catco don't know what they are doing!

 

This is a shot in the dark. Does the vibration change in anyway when turning left and/or right?

 

at slow speeds its nonexsistent, I don't really feel it until about 3000 rpm, so I guess to answer your question, no. why what are you thinking?

 

I was a dummy and left the car sitting in the garage for 4 years? Hehe! brand new tires too. I'm living with them for now till I wear them down a bit. It does smooth out with driving, but seems to come back if you sit again.

I had an extra set of rims/wheels in the basement for my wifes car and they fit. so I went out for a spin and I was all smooth, so I knew it was the tires. maybe I need to do some burn outs to "smooth them out" a bit hehe! I kid I kid.

 

Did anything happen with your trans mount?

 

Train of thought is... When turning, your rides center of gravity and weight changes. Possibly causing something or another to act up.

But if your problems exsists only at speed and rpm. I guess I'm at a loss.

 

could be a bad motor mount...motor torques when u get on the gas to the right i believe...so check your left motor mount could have cracks in it...im also trying to drive out a vibration after installing umi sub frame connectors, trans mount and new poly trans bushing and new tko 600 trans and rebuilt modified stock driveshaft with all new joints and yoke...even rebuilt the rear end and new bearings and did my front alignment mine is rpm sensitive...today i went up to speed it vibrates stuck it in neutral and it went away so im thinking it might be my new clutch..i dont think its flat spots on tires car only sat for like 2-3 months...but vibration isnt to bad and im not ganna be going 90mph anytime soon unless a giant tidal wave is in my rear view mirror lol...but i am leaving friday to drive 1200 miles...so im trying to find the vibration before i leave

 

no new updates, car has no motor right now, i'm awaiting my stroker in a week or two. while it has been out I've had the converter double checked for balance (8 grams off he said, not enough to make a difference he says) but I'm interested to see with the new motor if that changes, if it doesn't then I know it's in the tranny or rearend. motor mounts are brand new, whole driveline has 1000 miles on it, i mean EVERYTHING right down to the bearings. I'll update in a few weeks when i get it up and running again! thaks fro the ideas guys!