Ok so i got a question. I have rebuilt my transmission and rebuilt my transfer case and got 4:56 gears. I started having humming noises that i swear that are coming from my rear end. I have taken it to the gear shop that did all that work and they said it was the transmission. I took it to the transmission shop and they say its the gears. Im stuck between a rock and a hard place right now. The humming only happens soon as it gets to about 30 mph once i switch into 3rd gear (standard). And huming through 3rd 4th and 5th. Soon as you put in the clutch and or take the gas off the humming goes away. Im pretty mechanically inclined. I swear its the gears. Im gonna disconnect my front driveline this weekend and see if it still does it. Can some body chim in and help me. The gear shop said they would change the gears out for me and redo everything. If it fixes it then i dont have to pay anything but if it doenst fix it i have to pay for the new parts and the labor.

 

Pull the rear drive shaft, and drive in front wheel drive. Report back.

 

How high is your lift and do you have a t case drop or sye?

 

I might be crazy here, but if you are still moving and put in the clutch the gears in the rear end are still moving so the noise would remain if it were gears (or driveshaft since that keeps moving too). I might be wrong though, not 100% sure how that whole thing would work just rolling along.

That is weird though, because the more I think about it, everything would be moving in the transmission as well, all pushing in the clutch would do is disengage the engine from the transmission. Just from the little bit you've said I would guess transmission.

Does the noise happen in second gear at 30MPH+? I know that that's revving it up a bit, but you shouldn't be at redline by those speeds. If it does it in second at 30MPH + then I would guess it to be gears. I'm grasping at straws though at this point...definitely curious to see how this one turns out.

 

I have a 4.5 inch lift. Shimmed 6 degrees with a sye in it and new drive shaft. NO TC drop.

It actually does do it in 2nd if you rev it up to 30 mph. Just did it on the way home and yes it does it. Never thought about it till figure id give it a try. I aint tryin it in 1st lol. You can have it in 3rd, 4th or 5th and if you engage the clutch then the noise goes away.

 

Has your driveshaft been balanced properly? Just throwing some ideas out

 

I took the rear driveline off. Took it up to 35mph and no humming. So it's either rear driveline or gears. Driveline is a Tom woods driveline that I got when I did the sye. It's been greased. But haven't had it balanced no.

 

Mine has a hum in the rear end. I suspect a bearing in mine. Same symptoms.

 

Ok, so put the front ds on the back now and test it. This will eliminate the drive shaft, or the gears in the diff.

....Maybe pinion too low? I used a 2 degree on my 6" lift with hack and tap.

 

I'd say it's not the tranny at this point. Like Kyle said, if you can fit it put the front DS on the rear and see if you get the same thing. If you do get the noise, then it's likely the gears or a bearing somewhere in the rear end.

 

Does the humming noise sound like hmmmmmmhummhumhumhmmmmmmmmmHMMMMMMMMMhmmmmmmmhumhu mhumHMMMMMMMMMhmmmmmmmmmmm
Or mmmmmmmmmmmmmmmmmmmmhmhmhmhmhmhmhmhmhmhmhmhmmmmmmm mmmmmmmMMMMMHMHMHMhumhumhum?

 

I will try the front driveshaft on the rear if it will fit tonight after work. Can update a little after 6 MST.

I have the sye and a 6 degree shim. Could it be to high?

LMAO GreenXJ21. Id say the 2nd one lol