Gear Whine after regearing

Switch brands too? A thinner oil was quieter?

 

Moose when I had my gears changed I could hear a light whine at about 60-70 then went away below 55 MPH. I took it back to the installer just to be safe and he jumped in the truck and drove like hell! AS I was hanging on he floored it and drove FAST/slow varying speeds about a 10 mile loop then said it wasn't the gears as it wasn't happening at lower speeds also. When I asked about using heavier oil he said it wasn't necessary, if gears aren't installed correctly NO matter the gear oil weight it won't keep them quiet. They installed Lucas 80w-90 heavy duty during break in and after 500 mile change I'm still using Lucas 80w-90 today and the whine is still there ever so slight, I really don't hear it much anymore after 12000 miles. Most of the whine was deaden after I installed 3/4 inch exercise mats in the bed and adding rubber grommets to the rear bed box attach points/frame. I wonder if the rear end vibrations is resonating through the composite bed?

 

Interesting. I'm really not bothered by it. It's almost a tire hum, but slightly higher pitched. Not loud at all, just noticable, as it didn't exist before. It's definitely more prominent at 65-70 than 55. Who knows. Just curious if there was an easy solution to eliminate it. No biggie

 

Yessir. I believe the 80-140 oil was the nitro branded stuff that came with the gears. I switched to Amsoil 75-90 front, 75-110 rear. It's been great (and quiet) from -15 up to 100.

 

Doesnt matter. If you go effing around with a new ring an pinion, you want to replace all seals and bearings.

 

You'd be an idiot to replace bearings with very low miles with aftermarket ones.
Check any top notch gear installers and they will not replace the bearings unless they have noticeable wear.
When East Coast Gear supply rebuilds diffs they leave the bearings alone unless needed to be changed because of wear.
Seals on the other hand I personally would just replace them but again a lot of shops don't being so new and undamaged.

 

So, its dumb but you agree with me?

Your truck, you do what you want. I prefer a new gear set to have all new parts.

 

No I don't agree with you at all!
Have your gears done they won't replace the bearings unless you request it.
They definitely will explain why there is no need to replace them but at the end of the day they'll do want you want for a fee of course.
Ask the forum how many had their bearings replaced

 

Bearing replacement during regear

Rear diff

0-50k miles, no need unless there's a bad bearing

50-100k miles, may be considered, but original bearings are probably still just fine

100k+, consider replacement

Front diff

Front diff only spins in 4wd unless you have an AWD vehicle, so really shouldn't need bearing replacement.

 

I am having that same sound. Did you figure it out? Is it normal?

 

I am no an expert by any means, but that sure sounds crunchy. If it was any other machine I’d be looking for a problem.

 

I have not figured out exactly what it is but based on other people on here who install gears, do not think they’re set quite right. I’m going to take it back to the people who installed them to re-evaluate the noise and hopefully break the carrier assembly back down and check the pattern on the gears.

 

Agreed, @Stocklocker!

 

Any census on what gear oil reduces the whine?

 

i also have a whine with my 4.88's and i decided to try the 75-110 amsoil. It's much louder now. not sure how it's quieter for you but i'm going to have to go back to the thicker stuff.

 

Interesting. I did the same going from 80W-140 in front/rear to 75w90 in the front and 75W110 in the rear. I too noticed better coasting, which translated to maybe .5mpg better overall. During winter with my short trip to work it is about 1mpg better since the fluid doesn't have much time to warm up (1.5 mile drive). However, my diff whine only worsened. I have nitro 5.29 gears that were loud at first and really loud now. Wish I had the same results as you.

 

Yea, beats me. I'm at 10+ months in with the thinner weight oil and stand behind my original statement. My whine is still much quieter. I'm about to order a second batch.

 

Has anything been figured out to at least reduce the whine? I put 85/140 in my rear diff which helped a little bit I still hear the howl when feathering the throttle from 55+, curious if there’s an extra method I can add on top of the heavier oil just to get the whine a little quieter at least!

note: I already have the back of the cab and all the doors sound deadened!

 

No. That's the solution even on factory gears. Sorry man. I mean, you could sound dampen the whole cab, but it's not really worth it.

 

Just out of curiosity, has anyone heard their front diff whining, or is this specifically something with the rear diff only?