My 99 2wd 4dr is making a scrapping noise from the front. Loud when cold, stops once warm. Stomping on it at 40mph and its loud, coasting it quiet. Hwy speeds it sounds find. No lights on and wheel feel tight....got to be bearing hub??????? Do motor mount fail on these? 165,000 miles

Thanks......Mike

 

Interesting. A 2WD. Noise from front. Not sure if it's engine or wheel bearing related.
Try this: When you first start it up put in gear, hold the brakes on and give it gas. Noise or not?

Motor mount test: Get helper, put in gear, hold the brakes on and give it gas. How much does engine move and how? If a mount's bad it looks like it's flopping around, if not ..it's gradual and being resisted.

Wheel bearing test: Get to 40, put in neutral, make sharp swerves left and right, then put brakes on lightly while swerving .

Note: See Rotti's post below, he stole my end game!!!!!

On the other hand I was posting lessons in diagnosis. Applianceguy.. if you want to learn stuff on how to deal with these things go through the steps, anyway.
Quit handing out fish, guys!

But if it's betting on cause you want... it's the AC clutch bearing ready to go. Backupbet : Dayco belt.

 

A motor mount getting quieter after the engine warms up? If the scraping noise goes away after it warms up that makes me think of a belt driven accesory. Maybe try taking the serpintine belt off when the engine is cold & starting it? It'll only run for a few seconds & then shut off but you'll be able to see if it's a bearing, pump, A/C etc.

 

I agree with Rotti, try taking the serpintine belt off when the engine is cold & start it only for a few seconds. My first guess would be the belt itself, the a/c clutch or tensioner pulley. But popping that belt off and starting it up while cold for just a few seconds will tell you if it's anything belt driven.

 

Lol sorry... my A/C clutch went out a few years back. You can run the windshield defroster & the A/C pimp will start & stop or just run the A/C & see if the grinding/scraping sound is there.

I'm not handing out fish. I'm mearly leading him to the fishing spot - he has to do the fishing!
Leading to the spot - try this to see what's wrong.
Him doing the fishing - figuring out what's wrong & fixing it.

 

abra-kdabra make the noise go away!!! there fixed it. yea im thinking too that the ac clutch is gone another thing gm is famous for.

 

Ok...I'm no dummy. If you have feet on the floor you feel and can count the scraps. Did the brake on - motor lift....good mounts..no metal contact. I can punch it 30 - 50 mph and make it scrape. when its not moving everything under the hood is quiet. Tearing it apart tomorrow.
I was thinking that punching it is taking the wieght off the bearing slightly
and letting get loose????????? This is freaken loud.

 

Nobody said you were a dummy. We didn't know the feet on the floor/seat of the pants feeling.
Could be a U Joint or something out of line. But it goes away after it warms up - have you tried the belt off start up?
Many vibrations etc go away/you don't notice at higher RPM's because of engine noise & or the frequency of the noise.
Just offering suggestions is all.

 

I'm sorry...this crap sucks. u joints only 1000 miles. How about this....The scrape speeds up as the wheels speeds up and will do it a little turning right. Got to be the bearing hub.......find out in the morning. This would be alot esier if the ABS light would come on!

 

Never even concidered 2 problems........Front wheel bearing took care of bad sraping noise but there still an annoying whine. Got under and noticed oil drip hanging from the pinion seal and the center of rearend wet.........SOB! the pinion bearing slightly worn??? Took me an hour to find a disc brake posi unit on craigslist for $150.00!!!
What REALLY suck is my buddy has ford explorer that never breaks down and had to use it three times to tow my blazer home ;-(