Hi all, Just joined, sold my 2 wheel drive ford crew Diesel and picked up a GMC 2001 crew with a 8.1. Truck has 100k on it, clean, but when ...

Hi all,
Just joined, sold my 2 wheel drive ford crew Diesel and picked up a GMC 2001 crew with a 8.1.
Truck has 100k on it, clean, but when I shift into 4 wheel, hi above 10 mph (electric push button on left dash) I get a pretty good clunk in the front end.
shifting at slow speeds, not to much noise, and everything sounds good once its in, and works as it should.

One mechanic, thats pretty good on GM said its normal with the 8.1.
Thoughts??

BTW, was going to go with a diesel but with fuel costs, oil change costs with adding in the cost of going diesel, figured I would try the gasser, plus all the high costs of injectors, and head gasket issues with both ford and GM when bying used.
This is just to pull my 33' fifth wheel toy hauler, so milage while pulling will be pretty close to the diesels(I hope). Other then that, its just a back up vehicle, so not to worried about mileage other wise.

Thanks for reading!
Mike

I have an 05 1500 and I get not noticable noise when going from 2wd to 4 high. Now, when you switch it to 4lo the transfer case clunks a bit, but that is normal.

zoomer10h wrote:Truck has 100k on it, clean, but when I shift into 4 wheel, hi above 10 mph (electric push button on left dash) I get a pretty good clunk in the front end.
shifting at slow speeds, not to much noise, and everything sounds good once its in, and works as it should.

I get the exact same thing in my 03. In most cases, I'm going pretty slow when I pop it into 4Hi (like when plowing), but in some cases I'm going fairly fast. After 1.5 years of use, it hasn't changed at all, so I'm not worried about it.