off topic a little (new 2007 GMC HD2500 crew cab gas pickup does not go into 4WD)

[Michelle K linnane]

Hi Guys
I know this off topic for this forum, but this is a big collection of people with pickup trucks that know
what they are doing. I just picked up a GMC 2007 HD2500 gas pickup (Automatic Trans).

I had friends take me out to albany to get truck and they did not want to leave until we could all
leave together to get my new truck. So I was in a hurry and did not try everything on the truck
which I will never do again. Picked up the truck on Saturday and on Sunday read the owners
manual on how the 4WD worked. My Tahoe it just had a switch this has shift on the floor.
My jeep had the instruction right over the visor. This one for the first time in my life I read the
manual.

After reading the instruction I tried in engage the 4WD hi. The light never came on. Did not want to
mess with LOW after I had a problem with high. Took over to friends to show him new truck and
he read manual too to see if I missed something we could not never get the 4WD light to come on.

We have just a little snow and pulled on the lawn and gunned it and Mike watched the front wheels
the only thing that spun out was back wheels so it is not engaging. (I called an left message with the
sales man, this morning). I was a little upset to say the least, the dealer ship is 45 minutes away
and my tahoe is in the shop being repaired so I can not take it today. I have to work. Will try and
get it out there in the next day or so.

2007 HD 2500 GMC The truck is gas engine, auto tran, the 4WD shifter is on the floor stick shift. The truck seems to be
well careed for has 75,000 miles the bed has spread in bedliner but it looks like it was never used.

Has anyone had a truck of this year or similar with these problems? Just curious I am going to make dealer
fix it, but was curious if this is well known problem with these trucks?

 

[Xfaxman]

Check your manual for the location of the 4WD fuse, and check it. If all the spare fuses are gone, it may have happened before.

This is a good place to check also: Diesel Place: Chevrolet and GMC Diesel Truck Forums

 

[Diamondpilot]

Its a manual engaging 4x4 system, no push buttons?

That era GM trucks prior to 08 have a bad transfer case. The issue is called pump rub. I have seen it eat up two GM teansfer cases, a 05 2500 & 07 3500.

Google "pump rub Chevy/GM"

I have got one working temporarily by moving the lever and having a buddy beat on the transfer case with a block of wood protecting it and a 3# sledge or better yet a dead blow hammer.

No matter what I would drain it and take a look at the fluid. It uses ATF, about 2 qts same spec as the auto tranny. Its a simple job. There is a drain plug on the bottom and a sight plug on the side you pump the new fluid in till it runs out. Save the old fluid to show the seller. The drain plug and sight plug are either a large internal hex or uses just a 3/8" extension.

Chris