Front Grinding Sound . .

[pwsigmund]

OK. 2002 4WD Yukon. Again. You're all probably tired of hearing about it. I had a front end grinding sound noticeable when slowing to a stop. Couldn't tell which side exactly, but it is in the front. My girlfriend said she heard it on the passenger side. I knew the test procedure, so didn't think more of what she said. Next day jacked up front. Left side had good deal (half inch or more) of looseness holding at 12 and 6. No movement at all on the right side wheel. OK, good. Replaced left side bearings. You guys helped along the way.

 

Verdict. Seemed OK at first, but next day still hear grinding noise. It's actually louder and a lot more noticeable. Girlfriend verifies on right side. She's right. We're in parking garage which reflects sound real well, and I can hear it on right side clearly. Girlfriend makes point, several times, of "I told you so". Ah, women.

 

Jacked up right side. Still tight top to bottom. Didn't expect it not to be. Bought another hub for the right side. I'm going to replace the *$ right wheel bearing one way or the other, but is it possible to have a growling bearing that isn't loose? Anything else it could be? Definitely at the front right wheel, and a grinding, almost snapping noise along with it. Wheel spins OK. I compressed the dual pistons taking the caliper back off, and they aren't stuck, so I don't think the brakes were hanging up. . Brakes don't show anything abnormal, although I replaced the pads a couple weeks ago.

 

Am I crazy?

[Jsdirt]

I have the exact same issue right now in a '00 Jimmy, left - driver side. When you turn right, it's loud as hell, when you turn left, it goes away. No excessive play on that side. A wheel bearing is the only thing that would make that kind of deep, bassy, growling/humming/vibrating sound that reverberates through the vehicle. Can easily hear it over the radio at moderate volume.

 

I'll change it when it falls apart. Bearings are pricey.

[Matt_]

paul... you mention a snapping sound- this could implicate the CV axle. A grinding/howling is usually the bearing and a snapping/popping is often the axle. Can you describe the sound in more detail?

[pwsigmund]

paul... you mention a snapping sound- this could implicate the CV axle. A grinding/howling is usually the bearing and a snapping/popping is often the axle. Can you describe the sound in more detail?

 

Well, there's definitely a grinding/groaning/vibration sound that is very pronounced. And that seems to have gotten worse the last 20 miles or so. But mixed in there are sounds like a clicking/flapping sound. I wish I could describe it better. With 135K miles, I thought it was worth a shot replacing the right bearing even though it isn't loose, and pulled the hub today. Should have the new one in Wednesday, and we'll see what happens.

 

What goes wrong with a CV axle? Is there a U joint in there? My boots are intact and look OK. With the hub off right now, is there any way I can check the axle? How is the repair? Sounds major.

[Matt_]

Here's what the inside of a typical CV Joint looks like:

 

Replacement is actually VERY easy. Unbolt axle nut, unbolt at differential, finnegal out.... and reinstall new one. It can often be done without disconnecting the balljoints and tie rods.

 

Let us know how the hub replacement goes. Grinding/howling is really a bearing noise. However if that CV joint is chewed up and binding, it may have the same effect. Grab onto the axle and try to wiggle it around. If there's any play, the joint is bad....

 

Where are you at again? With all your issues I kind of want to come by and have a look for myself

[pwsigmund]

Here's what the inside of a typical CV Joint looks like:

 

 

Replacement is actually VERY easy. Unbolt axle nut, unbolt at differential, finnegal out.... and reinstall new one. It can often be done without disconnecting the balljoints and tie rods.

 

Let us know how the hub replacement goes. Grinding/howling is really a bearing noise. However if that CV joint is chewed up and binding, it may have the same effect. Grab onto the axle and try to wiggle it around. If there's any play, the joint is bad....

 

Where are you at again? With all your issues I kind of want to come by and have a look for myself

 

Matt

 

Thanks for the picture. I didn't know what a CV joint looks like. I got the right hub off yesterday. It was badly rusted inside just like the left side had been, and I couldn't get it off again without the help of an air chisel to wedge it out. Unfortunately that tears up the dust shield, so it was back to the dealer to order another one. But besides having to wait a couple days for it to come in, $15 is a small price to pay to get the hub off. The hub I could get from my NAPA dealer in town.

 

Right now the truck is sitting jacked up with the axle shaft "hanging out" of the knuckle plate. If I could replace the CV without having to remove ball joints, I think I'd spend the $ for a new CV just for insurance, since despite all of the rust underneath and the 135K mileage, I'd like to keep the truck for at least a few more years. Don't I need a special tool for the boot though? Now that the rusted hub has been busted free and will be replaced, the worst part is done, so taking it back out if I had to wouldn't be that bad. But I'd rather replace it all now if I could and be done with it.

 

Not sure how to determine "play" as you mentioned in the CV axle. The axle shaft seems plenty free moving around in a circle, and with effort I can push it in and out. Don't hear or feel any binding. Guess I'd have to support the front end differently if I did try to get the CV out, as I jacked it up by the frame, but have it supported under the lower wheel control arm. I'll have another look at it today, and try to post a picture tonight.

 

I live in Randolph, about 10 miles outside of Morristown. Wish you lived closer.

 

Thanks for all of your help!

 

Paul

[gmtech4]

i think skier works for a parts company and paul has got sucked in to throw parts at his truck,good job skier

 

i've never replaced a cv joint,even on an oil patch truck ,but whatever,your yukon must be just bagged goin for groceries paul

[Matt_]

yea.... cv joints never go bad. its so unheard of i must be off my rocker :rollseyes:. nice helpful post...

 

paul, when replacing the cv axle you repace the whole thing. look at where the other end bolts to the diff. no special tools needed.... they're usually $120 to $150. if it doesnt feel like the internals are binding or grinding when you move it by hand its probably fine. id leave it in, you can replace it later without taking the hub assembly off.

[SEP]

I have similar issue with my 01 Yukon but on the left side. I've replaced the wheel bearing and still does it. I thoght about the CV joint too but then after checking my FSM i found that differential bearing could make the same sound as wheel bearing so i'm going to get the front diff checked to see if it can be the problem.

[Matt_]

yeah failing cv's usually make a clicking or popping sound. if you're just hearing a howling/grinding its more than likely a bearing somewhere.

[jrod332]

What other bearings in the front end could be making that kind of a noise other than the wheel bearings. I have this kind of growling noise in my front end that I cant seem to locate. I have checked both the wheel bearings and they seem fine. No noise when i spin the hub and they feel smooth. I dont feel like just replacing the wheel bearings to find out that its not it. What else could I check?

[Matt_]

take the front tires and the front driveshaft off and try spinning the pinion by hand to see how those pinion bearings feel. The seep hole in the is known to gunk up over time and prevent the pinion bearings from getting lube.... its not an extremely common issue though because most of the time the front diff is disengaged. It could also be the axle bearings. Might want to try disconnecting the CV axles from the diff and spin the flanges. They also shouldnt have any lateral or vertical play and should spin smoothly.

[millhouse49]

did you replace the rotors? and if so did you have to beat them off? if so then it more then likely needs a hub on that side. the front diffs are also bad for making noise.

[jrod332]

I didnt change the rotors so im not sure how badly they are on there. How can I check the front differential?

[SEP]

I found the problem in my case which could be the same for you. Grab the CV where it meets the flange in the differential. Try to move it, up/down/left/right doesn't matter. If it moves it's bad. I now need to replace the output shaft bearing.