a chattering/rubbing noise thats driving me insane!

[Destroyer000]

so here is the issue, i have a 95 4x4 an iam getting a wicked rubbing sound, vibration in the front some where. it only happens when my hubs are LOCKED an the truck is in 2wd.. sounds like a shaft rubbing on metal or something. i checked the front drive shaft an the axle shafts an their fine. all the u joints are good. all axle shaft u joints have been replaced, spindle bearings have been replaced. when the truck is in 4x4 its fine an their is no noise. i did however notice that when its in 2wd with hubs locked , if you depress the clutch pedal the sound goes away.. i cant figure out what the issue is what so ever. i just started doing this last weekend . its driving me INSANE!

any one have an idea what might be the issue?

 

[razrwild]

shot in the dark but have you checked the fluid in the diff? Other guess would be how is the angle of the front shaft? any interference from crossmembers or anything?

 

[Joe400]

I would check the fluid level inside your transfer case and front diff, although if your clutch being engaged stops the noise in 2wd, it can't be the front diff... my guess is tcase

 

[holyford86]

when the hubs are unlocked the sound goes away as well, correct? so sounds from the tcase would still be present if in two wheel drive with the hubs unlocked if that's where the problem was. does the sound still persist with the tcase in 4x4 and the front hubs unlocked?

 

[Destroyer000]

the sound goes away when hubs are UNLOCKED only does it when their LOCKED an truck is in 2wd... once its in 4x4 it goes away as well.. front fluid is good tcase fluid is good all u joints are good ... the hubs seem to be good too.. iam stumped

 

[Defective]

This is happening to me too. exactly as you've described.

I've gone through my axle completely and everything looked good except the little needle bearing in the spindle was dry and my seal was compromised.

Sometime the noise is really loud and feels like a tire out of round or something. Kind of a romp romp romp as you go down the road. Especially at speeds around 35-45. Higher speeds it almost dissappears again.

I've been trying to determine if the hubs can do this. I've got manual looking hubs.

I've put hundreds of miles on it like this without much change now. Was kind of waiting for something to get worse to find the cure at this point.

 

[Kyle M.]

Well, if the hubs are locked, and you are in 2WD, the front wheels are turning your front driveshaft, inturn rotating the internals of the tranfercase. I don't know much about the transfercases, but I know some are chain driven, maybe by changing the load direction from inputting from the front driveshaft and not the tranny it is making the chain rub? Basically it is all freewheeling inside of there. Or maybe you never become fully disingaged? That would explain the noise going away once it in in 4WD

I don't know, just my ideas....

 

[Defective]

Wanted to follow up a bit on this.

Yesterday my t-case started sounding like a blender chopping ice when in 4x4 with hubs locked. Sounds like a bearing let go. It still works, but sounds pretty horrible. I'll be replacing it and tranny over the 4day weekend. I'll let you guys know exactly what I find in there.