Rear-end Grind (96 Cobra)

[cobrachris96]

I have a 96 Cobra with approximately 112,000 miles. I bought it brand new in 96 and have only made a couple of mods (4.56 gears and Flowmasters). Anyway, my problem is that I hear a grinding sound from the rear of the car whenever I hit the gas in 1st gear. The grind isn't bad if I take off slowly, but if I take off fairly fast, the grind is worse. I can feel it through the gas pedal too. What could be causing this? Gears? Transmission? I'm not a mechanic by any means, so I'm not sure what it could be. Any ideas from the Stangnet faithful would be greatly appreciated. Thanks!

 

[Superhereaux]

how long ago were the gears installed?

 

[cobrachris96]

The gears were installed approx 2 years ago.

 

[slow96mustang]

maby your pinion is loose. that's bad.
you sure its a grind and not your u joints?

 

[cobrachris96]

What kind of sound/feeling would I get if I had bad U-joints?

 

[PiranhaGT]

I had this same problem! I took the U-Jont off to find the bearing were powder instead. U-Joints are like $15 with that many miles I would replace them anyway. Mine totaly went out when I was on the highway and I thought I lost my clutch cause I couldn't go over 55mph.