HulkMJW

Ok i have a 98 cobra with 44k on it I just had a very trustworthy Alternative Auto in MI who strickly work on stangs amoung other ford products install some new 4.10 gears and I had them replace all the bearings axles outers, carriers, and input shaft bearings along with the gears and I know all my tires are balanced i Just had new tires installed today and I am getting a bad vibration noise at 85mph and up so im thinking it might be a bearing in the rearend causing the noiseor something in the driveshaft which i checked to make sure that was tight and the Ujoints were good so any help would be appreciated

QuarterMileMaster

You had a lot of work done... so I'm guessing you paid a lot of money too. You need to take it back to them and make them find out what's wrong with it.

HulkMJW

I spent 600 total with tax for the Ford Racing 4.10 gears installed with the bearings. So basically I rebuilt the whole rearend besides the limited slip which it hadnt worn out yet so i didnt bother but im prob gonna take it back to get it fixed so thankx for the reply

RuffCat

Tires can still be out of balance when you get up in the MPH especially with the stick on weights. Also, do the gears whine at all when you let off the gas or give slight gas? Or does it just vibrate? Vibration is one of 3 causes..1.u-joints are worn(you prob can't tell by looking at them)...2.driveshaft is out of balance(maybe they dropped it or it was like that and you hadn't noticed it)..3..Tires are out of balance. Gears will whine and grind and moan and that's about it. They don't give you a vibrating feel like u-joints do. My guess is that the gears are much tighter than what you had before and all the sound transmits though the tight linkage as before it probably got drowned out and washed away for the most part!

SVTCobra97

i had a similar problem with my 97 cobra and all it ended up being was my drive shaft was unbalanced.. have you had that checked at all??