Pinion bearing preload to tight?

[gradysjeep]

Well I just had yukon 4.56 gears installed in my Dana 30 and I'm getting what I think is some slight gear whine. It only happens at speeds below 15 miles an hour most audible when I'm decelerating/coming to a stop. Can hear it on accleration a little bit. Its not that loud though, the windows have to be up radio off to hear it. Anyway I'm thinking this is being caused by a tight preload. When I got it back the guy who set them up told me he set them at 18in/lbs which was a little heavy but he didnt expect any problems. the yukon booklet calls for 10-15 in/lbs but i guess they wouldn't set up well in that range so he set them at 18 in/lbs and called it good. Am I going to have any harsh affects from this over time or is it ok? I would hate to ruin brand new gears but if its just going to make a little noise and not hurt a thing i don't really care. My jeep has plenty of noises.

[Comanchedude]

Originally Posted by gradysjeep

Well I just had yukon 4.56 gears installed in my Dana 30 and I'm getting what I think is some slight gear whine. It only happens at speeds below 15 miles an hour most audible when I'm decelerating/coming to a stop. Can hear it on accleration a little bit. Its not that loud though, the windows have to be up radio off to hear it. Anyway I'm thinking this is being caused by a tight preload. When I got it back the guy who set them up told me he set them at 18in/lbs which was a little heavy but he didnt expect any problems. the yukon booklet calls for 10-15 in/lbs but i guess they wouldn't set up well in that range so he set them at 18 in/lbs and called it good. Am I going to have any harsh affects from this over time or is it ok? I would hate to ruin brand new gears but if its just going to make a little noise and not hurt a thing i don't really care. My jeep has plenty of noises.

I don't think that preload is the issue, generally wining noise is due to the gear mesh, its the setup. he may have the gears to tight and this can cause overheating and damage to the gears. but I have read some people have run noisy gears for a long time so you would have to wait and see.(i don't recommend that)
I have setup 5 axles correctly myself and they all run quite. now the 18 in/lbs is close enough that it could be the way he took the reading IE ring gear installed will add a bit of resistance. or the tool could be off? but if its tight worse case the bearing goes out early and if it did/does you should be able to feel side play in the pinion by moving the yoke by hand.if that has no side play its most likely your gear setup and I would open it up and check the gears. run a pattern and see what you have.or ask the installer to recheck the pattern and correct if needed.

[traitor5150]

That is not too tigh at all. I always set mine at 30 and I know a Jeep tech that works for my family dealership that sets them closer to 40 in puonds. He taught me how to set up gears has been doing it for years and swears it is the way to go because they loosen up as they wear in. Ive always done it that way never had any issues,

[OLAK]

I concur. Dana says 20 to 40 for new bearings is normal. The noise you describe is gear noise

[jpcherokeekid]

Once you get that gear noise, it will never go away. So now you just have to deal with it unless you put new gears in it.

[OLAK]

Originally Posted by gradysjeep

It only happens at speeds below 15 miles an hour

I would say just go faster