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Discussion Starter #1
Hello everybody. It's been a few years since i've been off the forum.. well a lot of stuff happenned, and i will update my street/strip project asap.
But at the moment i am dealing with an annoying driveline vibration.
A few months ago my mechanic took off the tranny to replace a rear main seal, and when i took home the car an annoying vibration between 55 mph and 70 mph appeared.
Then i took the car back to the guy in december to solve that and also install some other things, and we found that a transmission support was broken, he changed that and it improved A LOT.. but a slight amount of vibration is still there. It seems to come from the back of my car, and only at that speed. It is not related to the rpm of the engine, but to the speed of the car (well, i tried driving the car at 55+ mph in second gear).
She does that only at a certain speed, and only cruising at part throttle.. if i slam the throttle wide open i can't notice the vibration.
He pointed the finger to my tires, being that the car has been not moved for a couple of years into another garage.
With my car home again, i tried to drive it with a different set of wheels and tires on the back, but they were damn old tires too.. but i decided to give em a try.
The car behaved exactly the same.
Well, he also suggested me to put hub centric rings into my american racing TT D wheels (that are lug centric of course) because conical seats of aluminium wheel lug nuts could get worn over time, and i already bought them, also if i don't think that the trouble stays here. I will try them anyway.

Well, as soon as possible i will crawl under the cougar to see if something seems to be loose, and i will also try to put a couple of jack stands under my rear axle to see if the car vibrates at the same speed with wheels spinning in the air. And i will try also the hub centric rings.
I suspect it could be my driveshaft but... it only has 2 years of life. Could also be worn shocks the cause of that?
I didn't had that problem before the rear main seal replacement.

Do you guys, have any other suggestion for me? how can i troubleshoot that kind of annoying stuff?:(
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