grinding noise in 2WD HI

**EdPDX** · 12-17-2008, 03:56 AM

The subject of this post was wrong- should be grinding in 4WD HI and LO Not so much in 2WD.

I don't have much experience with 4x4s. Today, because of the 3" snow we just got here in Portland, OR, I drove the Mrs to work. I put the transmission in 3Rd gear (automatic) and the transfer case gear in 4WD HI. Along the way I noticed a bit of a clunking, then a more serious grinding. It sounded like it was coming from the tranny or Transfer Case, so I put the Suburban in 2WD and the noise went away.

Earlier in the year I noticed what sounded like a sickly bearing- I suspected a tail bearing housing as it sounded like it was clicking like a ball bearing dropping to the other side when I moved at a crawl. I have not serviced that; but today I got the idea that I should have. Does one have to do with the other? what is this grinding noise?

Ed

98 GMC Suburban 1500 4WD SLT

**04sierracrewcab** · 12-17-2008, 07:45 AM

is there a correct amount of Oil in the Tcase?

**JMoney02** · 12-17-2008, 08:32 AM

Originally Posted by 04sierracrewcab

is there a correct amount of Oil in the Tcase?

04 is right check the Tcase, do a drain and fill if possible and go from there, see if noise returns....
How often have you used the 4WD feature?????

Jeff

**retired** · 12-17-2008, 09:49 AM

Grinding in the transfer case is not good, take it and have it looked at. Get ready to have it rebuilt.

**GaryL** · 12-17-2008, 10:20 AM

See if this might be what you are experiencing.

http://www.gmtruckclub.com/forum/showthread.php?t=2509

**EdPDX** · 12-17-2008, 09:14 PM

I don't use 4WD except when the snow comes- not since last year.

I would order the Gilly's Kit; but I need my truck pronto, so I guess I'll get a replacement snap ring... and what else do I need while I have the Tail shaft out? I am not sure of the procedure. Pull u-joint, Back tail shaft off. Remove bolts for tailcover. Then what broken or Not broken Snap ring, then what, bearing?

Is that all the parts that I can replace w/o diving into a full TC R&R.

Where can I get these parts? And are there better after-market parts I can get without having to special Order? I live in Portland, OR so I guess someone should stock them right? What are the actual part names... I dont want to end up with the wrong thing.

Ed

**EdPDX** · 12-18-2008, 06:15 PM

Just got back from the Dealer to get Snap Ring, seal, and Output Shaft bearing. I was gonna tackle the job this afternoon in my brother's garage.

The dealer only had the tailpiece extension seal- no Snap ring or Bearing. I was on my way to the dealer that had one and decided to ask the service dept what they would charge for the work. The women did not know what I was talking about so she called the mechanic that does the tran work.

He advised, sfter a test drive, that it was not the snap ring. In fact the trasmission/transfer case I have was the NP8- no snap Ring to break.

He advised that the front differential was the problem and that 1200.-1300. would solve it unless the gears were all gone- add 600. more.

What exactly the problem was is that the crush ring was loose or warped or something.?!?!?

Sound Right?

Ed