Gear whine

So I got my truck re geared to nitro 4.88 gears. I went all the way to Washington to have them do it since no one around here will touch these new trucks. I broke the gears in exactly how I was told. Baby them for the first 500 and change the oil. I also did the heat cycles right after they were done. Now I’m having gear whine when I’m decelerating. You can hear it from 25mph and up. When you come off the highway you can really hear it even over the radio. I called them and told them what was going on and i was told “you should be fine”. I’m finding that people say it’s a problem and some say that the gears just make noise. This doesn’t seem right to me. What’re your thoughts. I have a short video where you can hear it but I don’t know how to upload a video on here.

 

Believe you, but not much you can do, its hard to prove if its the back lash/preload or if its the gear set itself causing the noise.

 

it sucks. I know I’m not the only one with this problem. I wish it was an easy fix.

 

I have it since upgrading to 5:29 gears, been thinking about putting in some heat resistant dampening to see whether it reduces the noise.

 

dont know if lifted
dont know if diff rotated
(actually changes fluid level)

if set up correct
breakin not critical

lash not correct
fluid low or both

 

I’ve been trying to find some kind of additive that would quiet it down. No luck though.

 

the truck just has about a 3” lift. I checked the fluid level today and it was fine.

 

Red Line makes more types
than anyone

Yet

if out of adjustment
its going to go bad

 

Is the differential aimed upward as a result of the lift?
Common practice was to overfill because of starving the pinion bearings.

 

I don’t believe it is. I have an ome bp51 lift. I don’t think it messes with the differential. I could be wrong though.

 

I experienced this after re-gearing my Wrangler. In that case, my carrier shims had somehow shifted and resulted in poor gear tooth alignment. It was an easy fix and I caught it before damage was done but I did have to inspect the diff to find it.

 

Not sure, but you can hear gear whine even in NITRO's own marketing video on Youtube.



You have to listen carefully in certain parts of the video but you can definitely hear it. For what it's worth the stock gears are also known to be noisy. The reason Toyota gives is that it's how the gear mesh vibrations are transferred throughout the vehicle.

 

over in the 5:29 mega thread, I thought I read that it's something to do with harmonics and isn't really a defect. But that's a long thread.
@JoeCOVA did I read that correctly, the whine doesn't indicate something is wrong, it's a byproduct of the types of gears?

 

I can definitely hear it in the video. My trucks sounds exactly like that. I guess I should be fine then. Hopefully it doesn’t cause issues down the road.