4X4 Noise

dgrammer · October 21, 2004

I just got my 2002 silverado a couple months ago. I haven't really tested the 4X4 out other than to make sure it works. Yesterday I took it off-road to test it out. When engaged it sounds almost like a bearing going out or something. Not real loud or anything, just loud enough to possibly be concerned about.

I wasn't sure if this is maybe normal. I haven't had any experience with any of the NBS silverados, but I know my 98 blazer didn't do this.

Any Ideas?

Bish · October 22, 2004

I just got my 2002 silverado a couple months ago. I haven't really tested the 4X4 out other than to make sure it works. Yesterday I took it off-road to test it out. When engaged it sounds almost like a bearing going out or something. Not real loud or anything, just loud enough to possibly be concerned about.

I wasn't sure if this is maybe normal. I haven't had any experience with any of the NBS silverados, but I know my 98 blazer didn't do this.

Any Ideas?

<{POST_SNAPBACK}>

Depends on what you are hearing. I hear driveline whine in mine when in 4x4 but it really isn't that noticeable. I'm at 130K so I dont think anything is whong with the sound I hear.

srmrvette · October 22, 2004

You need to check the lubricant in your transfer case NOW. Use the fill plug which is at the rear of the TC.

I have had 2 TC rear seals replaced at a GMC dealership, because they leaked. After the 2nd one, I did not notice any leaks, but some months and miles later when I had to use 4wd there was a terrible noise. Checked, no fluid. On the first seal change they list the p/n of the special lubricant. On the 2nd seal change they mention a flush and they tell me this is a kit which includes the fluid. Anyway, they say I need a new TC at $2600 plus.

dgrammer · October 22, 2004

Well it is going to the dealership in the morning to get checked. I did notice the other day there is a small seap forming where the transmission and motor bolt up but didn't notice anything at the transfer case.

dgrammer · October 23, 2004

Well I took it to the dealership today and they said it sounded like a bearing in the front differential going bad and I will have to let them have it for a day or 2 to find which one.

Also I was talking to them about tightening the torsion bars and they said it will not hurt anything and will not void any warranty. The shop manager said GM designed them to not neccessarily be used for lift, but to work within spec when cranked up.

As far as the ford keys or aftermarket keys, they will void warranty but he also said if they were not cranked all they way as to be very noticable they would probably not say anything or even notice.

srmrvette · October 23, 2004

It hasn't happened yet, but I now understand the GMC dealership is going to install a new transfer case in my truck, at no cost to me!!! Hope you get results as good as I have been promised.

garyandtricia · October 23, 2005

Yes, the transfer case. I've had three front diffs replaced in my 2002 avalanche. On the third one they said that the transfer case was too tight(it has a clutch pack in it). That caused pinion bearing wear. GL