camar0rs

I had a cover leak so car was going to the shop regardless

shop indicated the gears were 3.73's and were worn

The whine was more apparent up to 50mph were it then settled alittle but still there...

They fixed 2 leaks, cover and front, and put in a new set of gears and apparently test drove

They said so far the whine is gone down but still trying to see what else is possibly amplifying the sound.... they did mention some bar was close and moved it away

I have read alot of articles that moser has a whine, some because nature of the beast or poor installs or whatever...

Realistically should i be excepting any whine?
car is no way close to stock

01ssreda4

iTrader: (96)

Depends on gears and torque arm. A body mount torque arm will amplify the sound. Some brands of gears are just a little noisy....some tend to be more quiet.

codyvette

iTrader: (24)

Good luck finding and or eliminating the noise. Welcome to the world of I should have bought a 9" or S60.

camar0rs

shop still has car after 2 days.... they appear to be scratching their heads at this point... new gears helped some of the whine

car has a UMI relocation and torque arm setup....

Bob@BruteSpeed

iTrader: (16)

A little whine is quite common and in many cases cannot be cured. Aftermarket gears are usually a little noisier (and stronger) than oem gears, and produce some of the noise, and in some cases noise will decrease as the gears break in. I recommend 500 miles without going wide open throttle to break in a set of gears to make them as quiet as possible. For many of us, that is extremely hard to do... Bob

camar0rs

so i have the car since yesterday.... whine appears to only show up between 40-45 now... in the break in period so keeping it easy here

they mentioned that the exhaust pipe appears to be sitting on the rear end once you have 2 people in the car and that might not help the noise so will have to have an exhaust shop take a look, might need a bracket....

they also mentioned that switching to a BMR arm might help, thoughts ?

Bob@BruteSpeed

iTrader: (16)

Anything that touches the rear can amplify the sound through the torque arm right up to the passenger compartment.

What torque arm do you have on there now? The factory torque arm is made out of stamped sheetmetal and is prone to bending slightly ahead of the rear end. The factory torque arm attaches to the transmission which is hard on transmission mounts but I doubt the rubber that is used in the way it is mounted will transmit much noise. Bob

camar0rs

i have the UMI torque arm currently with the relocation kit

01ssreda4

iTrader: (96)

That's a big part of the problem. That's like a megaphone for noise into the cab.

Bob@BruteSpeed

iTrader: (16)

I agree. It's the better way to mount a torque arm, but it does amplify and transmit noise. Bob

camar0rs

so basically i should suck it up then? lol...

someone was trying to tell me the BMR would be better but from what i have been reading, its basically the same

Bob@BruteSpeed

iTrader: (16)

Both brands do a very good job of removing the forces the transmission mounted torque arms place on the transmission. The only way I can see that one brand could isolate the noise better would be if it had spongy rubber mounts, which isn't what you want in a performance torque arm. Bob

bobby5

I have a Moser 12 bolt and after a couple 5500 clutch dumps with slicks it got extremely noisy. Popped the rear end cover off and everything looked normal. Apparently the gears were stretched from the launches. Put a new set of gears and everything was quit then went to the track a couple times and noisy again lol . Everything held up good just gets noisy after a few times to the track.

camar0rs

i am still working on the 500 miles on the new set... whines starting at 40-50 range but seem to drop off some after.... does seem letting off the gas you an feel the whine through the emergency brake handle.... so annoying....

bobby5

yeah mine is the same way the torque arm amplifies all the noise

Bob@BruteSpeed

iTrader: (16)

The factory 10 bolt that came in these cars has a very small 7.5" gear. A variation of this rear was used back in the '70's in the Chevy Monza, then in the Chevy S-10. GM had to of known they would have warranty claims when they decided to use this rear in the 3rd and 4th gen f body's, apparently the cost of creating a stronger rear was higher than what they thought the warranty cost would be. This has been a real plus for the aftermarket, as a bone stock LS1 F Body with a manual transmission can break one of these 10 bolt rears! Many people have tried to beef these 10 bolt rears, spending a lot of money in the process. What they normally end up with is a rear that still breaks, as everything on these rears is too small.
The 12 bolt rears that are available for these cars is a step in the right direction. The 12 bolts are well known for being a stout rear that was a factory option back in the day in many performance cars. You can have a 12 bolt in an early Chevelle, Nova, Camaro, etc, and beat the snot out of it and not hurt anything. Put a 12 bolt into a late model f body that uses a torque arm, make a couple 4000 to 5000 rpm launches at the dragstrip, and I can just about guarantee you'll have a lot more gear noise on the way home. The torque arm seems to distort the housing on the 12 bolts, and it seems to happen to all the brands of 12 bolt rears. This does not happen to the 9 inch rears, and there is no price difference between the 12 bolt and nine inch rears. As the horsepower in our engines keep escalating, most people these days go straight to the nine inch rear. The 9-inch has an internal rear-pinion support that also supports the gear end of the pinion to limit gear deflection under high torque loads. This seems to be the major reason why the 9 inch doesn't start whining after high rpm clutch dumps, when the 12 bolt will pick up noise. The 9-inch locates its pinion gear lower on the ring gear to improve tooth contact, better the 12 bolt does. The 9-inch also has a 0.125-inch larger ring-gear diameter and internal pinion support than the 12 bolt. Bob

codyvette

iTrader: (24)

Damn Bob, That should ba a banner for the main page here at tech. Hopefully plenty will read and more importantly, LISTEN to this. Thanks

RockinWs6

These 10 bolts were in the late 70's and 80's Impalas too but used a smaller diameter axle.

DANSBIRD

iTrader: (2)

After 15 years and 228k miles, I'm still rockin' my original 10-bolt. Despite the car putting down 460rwhp. The tires have been the only thing that's kept the rear alive. lol

But, I'm about to pull the trigger on a 9".

HCI2000SS

iTrader: (2)

I know what you mean lol.17 years for me but with 90k and about 600 rwhp through a M6 and 4.10 gear. DTS is like an hour from me, and i'd love to get one of their 12 bolts, but after reading stuff like this I may do their S60 instead