Hi,

I have a 2007 Suburban LTZ with a transfer case problem. The other day I heard a grinding noise for a few seconds whilst driving slowly with the selector in AUTO, it then dissappeared. Today the noise came back, but now even when the car is not moving and I shift gear. It doesnt seem to matter what gear I am shifting to or from. The noise goes away when in 2WD. I managed to record the noise.

https://youtu.be/Tx-b4Y_ldjo

Any ideas what could be wrong? I read something about a snap ring, is there one on the output shaft for the front that could break? Thanks

 

Running it on a lift is the sure way to listen to see exactly where the noise is coming from is a first step. Everything else a just a guess.

 

We have located the noise to the transfer case. We discovered that it makes this noise even when the engine is not running and I am shifting gears in 4wd/auto mode. I am thinking maybe it has to do with the transfer case electric motor somehow...

 

Encoder motor likely cause but how long since fluid was changed and are you driving in Auto or 4wd on dry pavement?

 

Fluid changed only 4 months ago and the old fluid seemed fine. I emptied the fluid again yesterday and at least I couldnt find any metal in there. I have been driving in auto for a while, I guess I must have forgotten to put it back to 2wd.

 

in auto you can drive on dry pavement , but not when in 4wd. I have had 3 jeeps , 2 of which I wheel off road at offroad parks , had np231, np242, and dana 300 transfer cases. 231 and 300 are part time , 242 is full time/ part time . the one in me surburban is a sorta of a full time with the auto selected and part time when 4 wd selected. part time is for gravel, dirt, snow, ice etc. full time can be used on dry pavement , but eats gas !

 

a wee bit off topic , but what boat is your picture ? I was plank Owner on USS Carl Vinson CVN 70 . I wheel jeeps now tho LOL

 

That is the USS Kitty Hawk CV-63. I was ships company from Feb. 1972 to Dec, 1975. Two years of Vietnam War and 2 years peacetime.

 

still off topic for forum , but once a SQUID always a SQUID I was HT/DC 78-83

 

You should read thru this thread I started on another forum that is all military stories: https://www.tahoeyukonforum.com/thre...-force.118133/