We have a 1994 Z28 with 297,170 miles on it. T-56 transmission, 3.73 gears, LT1. Last summer the pinion seal started leaking. Shortly after that the rear end started roaring. I thought it was the carrier bearings and maybe the pinion bearings, so I changed them all. Checked the gears and axle bearings, found no damage. After re-assmebling I road tested and the noise was still there. After talking to a few people about what had happened and what it was still doing, we all came to the same conclusion. The gears were burned up even though they looked fine. Ran the car for 10 months, the noise didn't get worse or better. Today I changed the gears out with a new set of Richmond Gears. Same ratio, new bearings, seals, and crush sleeve. Filled with Mobile1 synthetic LS gear oil. Ran the car on jack stands for 15 min. Checked everything over and road tested. Still exact same roar. Any ideas?

 

nope, but mine did the same EXACT thin with 3.73s except for i havent replaced mine yet, the roar isnt too bad. my pinion is a bit over heated you could see,

i have heard richmonds wine a little bit

 

The gears I took out were GM 3.73 gears and they made the same noise as the Richmonds. I don't really think it's gears anymore. I'm leaning more towards rear end housing. I'm not 100% sure yet. I'm going to pull the rear end apart and check the axle tube alignment in relation to the carrier bearing saddles. I'm thinking with that many miles and that many hard launches something has given. Like I said, I'm not sure but it's worth a shot. Thank you for the reply.