Possible U joint, possible drivetrain issues....HELP

[sassyboots]

Hi everyone.

I have a 2008 Envoy that I love to death. Great little SUV, so sad they quit making them.

ANYWAY

I am getting what is best described as a "whirring" noise when I accelerate in regular 2wd. The noise gets progressively worse if I am in "auto" and then it just sounds awful when I put her into 4wd. 4 hi, not 4 low.

She also seems sluggish on acceleration. Went on a road trip this summer and could not seem to get the peppy power I am used to on this vehicle. Seems like the engine is also working pretty hard coming off a dead stop and trying to get her up to speed. I had all the maintenance fluids done with an oil change about a year ago, the only thing that wasn't changed at the time was the transfer case and that was because they said it still looked ok. I keep regular oil changes done and have the fluids checked when I should. This includes the front and rear differentials. They didn't mention anything of note last time I had the fluids done.

I also noticed today that if I am shifting from 2wd to auto to 4wd in my driveway with the car in park and me leaning out the open window, I can hear the noises quite well; I don't remember being able to hear them before, but then I wasn't trying to, either. When she goes into 4wd I can hear almost like a small grind and then a click. A fairly loud click. I went into 4wd while driving on dry pavement today, just to check things out, and had a pretty good noise when I did so. Not a huge noise, but I know I've never heard that before.

The car pretty much howls if I put it into 4wd even at low speed. I'm too scared to see how long the howling lasts or if it gets worse as I speed up in that gear.

Hope someone can shed some light on this before I take her in for a check. Lots of mechanics just see dollar signs when a woman walks into a shop and I am a widowed single parent, don't really have anyone else to help me out with this.

Thanks in advance.......

 

[Gmcguy6677]

Hi. I would be looking into the possibility of a seizing caliper or bad wheel bearing. CV axles and U joints would have clunking and vibration which is more noticeable on acceleration. The noise you hear in the front is the electric motor engaging and/or disengaging the front end gears which is normal and sometimes will have a clunk depending on the sync/mesh alignment of the gears. If the engine doesn't seem peppy but all is fine, ie: spark plugs, air filter and fuel, then I would lean more toward sticking brakes.

 

[Gmcguy6677]

Hi. I would be looking into the possibility of a seizing caliper or bad wheel bearing. CV axles and U joints would have clunking and vibration which is more noticeable on acceleration. The noise you hear in the front is the electric motor engaging and/or disengaging the front end gears which is normal and sometimes will have a clunk depending on the sync/mesh alignment of the gears. If the engine doesn't seem peppy but all is fine, ie: spark plugs, air filter and fuel, then I would lean more toward sticking brakes.

You could possibly have a siezed u joint in the front drive shaft.