Kevova

I got a 3.73 assembly from a member here several years back. It been in the car for about 2k miles. It had a little whine I attributed to the poly batwing bushings amplifying noise. I rarely drive car with windows up, but it was 30 degrees. It has a US Gear gear set. It seems louder than I remembered. It's quiet on float and coast. Noticeable on accel and cruise. Does anyone have experience with US Gear?

84 4+3

Depending on gear mesh you can cut them where they will make noise on acceleration and not when coasting. Do you get the whine in reverse? That would say if it's the gears themselves or the setup...

Kevova

I don't drive in reverse far enough to notice. Most of the gears I have dealt with have have been oem. I have heard of some aftermarket gearsets being noisier than others.

rjacobs

gear noise on a low mile setup is usually attributable to poor gear setup...

USA Gear is pretty good quality. Almost all aftermarket gears are made in Korea at the same factory so no big difference between USA Gear, Motive, Yukon, etc... Real Dana gears are made in USA, supposedly.

ZWILDZR1

I have experience with gear noise but not with the Dana 44 & 36. I decided to go from a 3.08 to a 3.73 ratio in my 77 Trans Am. Not having any experience with setting up differentials I got a friend who worked at the shop next to mine to do it. I gave him a new Richmond 3.73 ring and pinon, all new bearings and races for the ring and pinon, and carrier along with a new crush sleeve and various shims. He said he couldn't get the crush sleeve to crush so he just used the old one. The car whined or hummed on acceleration and went away on deacceleration .

I ended up having to buy all new bearings and races and having a guy who worked at the local Chevrolet dealer redo it as a side job. He asked me how it was done. When I told him about the guy using the old crush sleeve he just shook his head and said he has no business touching a differential. He always gets them to crush. He was able to use the same ring and pinon. The car had been driven less than 100 miles. But in that time a wear pattern had been established. The car had a whine or hum passing through around 45 m.p.h. So I just didn't cruise at that speed. Plus the car was loud enough I never paid any attention to it. What was happening with the old crush sleeve was the pinon gear was walking in and out on the ring gear. It doesn't take long to establish a wear pattern.

383vett

The guy that set up my rear end for racing said that noise is ok when decelerating, not ok during acceleration.

Kevova

I figure pinion depth is off, the risks of buying used parts. I have several months to decide what to do about it. Install loud radio and straight pipes .lol

PatternDayTrader

Its probably to.late to change anything. Meaning even if you set it up.properly now, it's very likely still going to be noisey.