Gears Whining REALLY BAD!

[GottaHaveLS1]

I just had my motive performance 4.10 gears installed in my m6 two days ago. The guy i had do it put my friend's gears in his 94 GT and was highly recommended. In the past two days I have put about 260 easy going miles on her with the new gears. I parked it and the gears were really quiet and the next time I drive it.. about 30 min later... the gears are howling really loud! Should I change the fluid? it's really loud i bet people can easily hear it when i go by. I was going to change the fluid tomorrow or the next day. i'm going to call the guy soon and see what he thinks. is there anything else i could do? 71k miles

[Wesman]

Sounds like they were set up improperly. If they were fine before the install, and they are whining after, then something is out of spec. Have it looked at before you either damage the gears themselves or the entire differential gives out.

[GottaHaveLS1]

I only drove it home after i noticed the sound (10 miles) and now shes parked. My guy told me to call him for anything so i'll probably call tomorrow. I put 100 miles on the car yesterday and 150 today before the rear started whining. hopefully the worse that can happen is that he has to take it apart again. I will check the fluid tomorrow and see if i should change it and probably get the limited slip additive. is there a certain type of synthetic oil i should get?

[roblelp]

I have 4:10 gears in my 2000 SS and was told prior that they would whin, and they do.

[badazta]

I had 4.10 richmond gears done in mine. They whine, the guy was upset because he said they they better then any he's ever done. He is highly recommended and told me 4.10 whine he doesn't know why. He told me when I ordered them to get the richmond gears because they are quiter then the motive. I used amsoil for the fluid. I'm not sure how bad yours are I chaulked mine up as a price to pay for performance.

[GottaHaveLS1]

hmmm, its so weird tho. there was hardly any noise for the first 250 miles!! if they're going to whine, then why so late after the install. it's only been 2 days but that's half of the break in period. I also did the heat cycles and everything. i hope this can be fixed or minimized at least. it was such a tease to have them so quiet all that time

[Wesman]

I only drove it home after i noticed the sound (10 miles) and now shes parked. My guy told me to call him for anything so i'll probably call tomorrow. I put 100 miles on the car yesterday and 150 today before the rear started whining. hopefully the worse that can happen is that he has to take it apart again. I will check the fluid tomorrow and see if i should change it and probably get the limited slip additive. is there a certain type of synthetic oil i should get?

Go with Mobil 1 75W-90 for gear oil. Its excellent oil and not too expensive.

[0rion]

hmmm, its so weird tho. there was hardly any noise for the first 250 miles!! if they're going to whine, then why so late after the install. it's only been 2 days but that's half of the break in period. I also did the heat cycles and everything. i hope this can be fixed or minimized at least. it was such a tease to have them so quiet all that time

the best thing you can do is have someone there that knows what they're doing listen to them and see what they think. They could be set up wrong or there could be nothing wrong at all. Noise is a price you pay for gear swaps usually but that doesn't mean yours is normal. Does in whine on accel, decel, or both?

[Z ROADSTER]

I only drove it home after i noticed the sound (10 miles) and now shes parked. My guy told me to call him for anything so i'll probably call tomorrow. I put 100 miles on the car yesterday and 150 today before the rear started whining. hopefully the worse that can happen is that he has to take it apart again. I will check the fluid tomorrow and see if i should change it and probably get the limited slip additive. is there a certain type of synthetic oil i should get?

Stay away from synthetic with A/M parts .

[SteveC]

Some gear sets whine more than others, it depends on the angle that the teeth are cut at, the more straight up and down the cut the more the whine.

SteveC :)

[GottaHaveLS1]

I dont think you guys are getting it. the gears were extremely quiet for the first 250 miles... not right after the install. I do remember downshifting into third and the rpms went up a decent amount but it wasn't a hard downshift... it was just to slow down. then i parked the car at my friends house and it cooled down for about a 1/2 hour. i'm fearing that downshifting messed up the gears and then they cooled down and hardened.

[GottaHaveLS1]

the best thing you can do is have someone there that knows what they're doing listen to them and see what they think. They could be set up wrong or there could be nothing wrong at all. Noise is a price you pay for gear swaps usually but that doesn't mean yours is normal. Does in whine on accel, decel, or both?

it whines very loudly on accel and decel. you can hear it over the radio even when it's turned up. when i take it out of gear, it's a little quieter.

[GottaHaveLS1]

i just got under the car and a lot of oil seemed to have leaked out where the rear connects to the driveshaft. i'm going to call the guy who installed them and see what he thinks. can anyone tell me how to drain the fluid out of this thing? theres no drain plug:wtf:

[0rion]

Just take the rear cover off.

There's a fill hole on the cover, use a rachet drive to take that out and stick your pinky in there and see if you can feel fluid. Sounds like maybe you're low/out.

[SteveC]

i just got under the car and a lot of oil seemed to have leaked out where the rear connects to the driveshaft. i'm going to call the guy who installed them and see what he thinks. can anyone tell me how to drain the fluid out of this thing? theres no drain plug:wtf:

USUALLY when people replace the rearend gears, they also replace the POS GM pinion seal with a solid pinion bushing, the installer may have damaged your existing seal, without a drain plug, you need to remove the entire cover to drain out the fluid, HOWEVER you can purchase a self taping drain plug that can either be used on a transmission pan, or rearend cover.

I purchased a T/A girdle, which is deeper than the stock cover and comes with a drain plug.

If you do not mind me saying, it sounds like you did not do enough research before entering the modification, at least in my instance, I do ALOT of reading, ask ALOT of questions, and then make my choice as to what I want to do.

SteveC :)

[GottaHaveLS1]

USUALLY when people replace the rearend gears, they also replace the POS GM pinion seal with a solid pinion bushing, the installer may have damaged your existing seal, without a drain plug, you need to remove the entire cover to drain out the fluid, HOWEVER you can purchase a self taping drain plug that can either be used on a transmission pan, or rearend cover.

I purchased a T/A girdle, which is deeper than the stock cover and comes with a drain plug.

If you do not mind me saying, it sounds like you did not do enough research before entering the modification, at least in my instance, I do ALOT of reading, ask ALOT of questions, and then make my choice as to what I want to do.

SteveC :)

I did plenty of research. I purchased the master install kit with the gears as well. i'm bringing it to the guys shop tomorrow and he'll take a look at it.

[Cutlass]

4.10 gears shouldn't whine any more than any other gear ratio, so thats total BS. Richmond gears whine more because of their cut. If your gears were quite then he set them up correctly and then something happened to make them noisey. ie low fluid level, something came loose (pinion nut, carrier cap bolts, gear to carrier bolts,etc). F-body pinion seals seem to be very difficult to seal up but they usually don't leak out all the fluid that fast!

[GottaHaveLS1]

i'm hoping it's something that just came loose. i'll be taking it to his shop soon.

[Z ROADSTER]

Question for all you rear end experts . Its a well known fact that straight cut gears are much stronger & louder that of helical or spur cut gears , although it takes more HP to turn a helical gear . What type of gear is the OEM gears as apposed to HD racing gears ?
ANYBODY ?

[Cutlass]

All rear gears are helical cut no matter the applications. Spur and helical aren't interchangable terms either. Spur cut gears are straight cut gears.
The difference between say Top fuel and OEM gears are the heat treatments. OEM gears are harder and more brittle and would basically explode in a top fuel car. Top fuel gears are soft and absorb shock load, but wear out faster.

[Z ROADSTER]

All rear gears are helical cut no matter the applications. Spur and helical aren't interchangeable terms either. Spur cut gears are straight cut gears.
The difference between say Top fuel and OEM gears are the heat treatments. OEM gears are harder and more brittle and would basically explode in a top fuel car. Top fuel gears are soft and absorb shock load, but wear out faster.

Oh ! Ok . All gears ? I've always heard that GM's M22 rock crusher transmission's had straight cut gears . That's why they were so noisy but very durable & would hold-up under those high horse-power 427/454 big blocks .
Also since I have your attention , is it true that the OEM axles in our f-bodies do not come heat-treated ? And is that why the soft bearing surfaces of the axle ends grind grooves into it so easily , necessitating replacement so often ? Also , is that why aftermarket heat-treated & chrome hardened race axle shafts make noise ?

[Cutlass]

I meant all rear end gears are helical cut, however I probablly shouldn't say that because I suppose there are examples to prove me wrong.
Yes I've heard of straight cut gears in manual transmission like the M22 and aftermarket T5's and that does indeed make them stronger.
I've never heard any about the rear axles heat treatment or not. It would be interesting to know. I'm not sure how a chrome hardened axle shaft would be noisey.

[GottaHaveLS1]

I dropped my T/A off at my guys shop. I was there when he took the cover off the rear and there were lots of metal shavings on the magnet. This was only after driving less than 40 miles after changing the fluid. He said the gears looked fine and nothing was loose (backlash was perfect). I called him later in the day and he told me that I blew a bearing in the rear end. He also told me that this could be the problem thats causing the noise so I had him order a new one. It was $47 and I'm picking it up tomorrow. what do you guys think?

[Eagle]

Its still going to grenade on you sooner than later... keep saving ur duckets for a new axle!

[Cutlass]

Bearings cause noise all the time in differentials, so yeah that most likely your problem. Question is how did it happen so soon??? Did he say if it was an axle bearing, carrier side bearing, or pinion bearing??

[intheclouds1977]

Proper breakin is VERY important for new gears. Did you follow the proper breakin procedures? If not, the differential will become excessively hot, possibly damaging gears and/or bearings. Could lead to gear whine as well. If you didn't follow proper breakin, this may be your fault and not the installer's or the product's.

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Fill with fresh gear oil. Drive for 20 miles without hard acceleration and at a steady speed. Do not exceed 60mph. Let the vehicle sit as long as it takes for the differential to become cool to the touch. Repeat procedure one more time.
For the first 100 miles, do not exceed 60mph. After 500 miles, drain/refill with new gear oil. Your new gears are now broken in.