Grinding Noise With Bogged Down Throttle On Take Off

[BobG123]

I have a 2004 GMC Yukon SLT with the oddball AWD that has the 4lo selection. I recently purchased the vehicle about a month and a half ago. When I test drove the vehicle it would make a grinding noise upon take off and throttle down. Sounded like the type of noise when ABS kicks in. I turned off traction control and it quit doing that. Made me think of CV Shaft or possible bad hub. So I figured it would be easy fix and bought it. Now I took it in to have it inspected. They tried to check the front diff and wasn't getting a reading. Pulled the drain plug and it was covered in metal shavings. So I was advised it needed a new diif. Ended up replacing it with a low milage unit wich only had 50k on it. They put new seals and fluid in it for preventative action. Replaced a few worn suspention componets and all seemed like that was to problem. Now the same symptoms still persist when trction control is engaged upon take off. I'm leaning towrds the wheel hub/or CV shaft still. They did put it on their diagnostic machine and all electronical componets checked good with the traction control and ABS. I will also add that this AWD is actually equiped with a G80 in the rear end. Read on the forum somewhere somebody said with the short run option, GM never put a G80 in these. RPO codes in the glove box says otherwise. Any help would be appreciated.

 

[Fless]

The first thing I would do is to put a capable scanner on it and graph the wheel speed sensors' activity to see if one is acting up.

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving sage advice from the knowledgeable folks on this Forum.

I recommend that you get yourself a quality bi-directional scanner to add to your tool box. Then, you will be able to read ALL trouble codes, along with a brief explanation/pointer to the source of your issue. You will also be able to reset/delete trouble codes, after taking corrective action. You will literally save thousands of dollars in diagnostic and repair costs over the life of your truck, and you will most likely recoup the cost of the scanner within 1 year.

 

[rockola1971]

I agree with @Fless and suspect a defective wheel speed sensor tricking the ABS control into thinking you are slipping and sliding. A bad wheel hub and bearing assembly will cause this also. Lift the front tires just up off the ground to clear and rock tire left and right at 3 and 9 o'clock position and then 12 and 6 o'clock position and if the hubs are bad you will feel it. Inspect for loose tie rods, pitman and idler arm that can trick you into thinking hubs are bad.