99 front end issue

[MikeD266]

Ok, guys. This is one of those PITA "it's making this noise" posts... bear with me.

1999 ext cab 4x4 5.3L 249k miles.

Had new tires put on in the last 30 days. Problem began 3 days ago.

"Grinding" noise like a wheel bearing gone. Seems to be coming from left front. Haven't had a chance to get it off the ground to examine yet. Bearing was replaced within the last two years. Noise remains when rolling straight and turning left. Goes away when turning right.

Noise doesn't increase/decrease with braking at all.

Also having intermittent issues with ABS activating at low speed - especially on left turns.

Would a wheel bearing - even a low end after market - go this soon? Or should I consider CV joint issues in this mix?

[kahjdh]

With the sound dissapearing when turning right my guess is right side wheel bearing.

[j cAT]

Originally Posted by MikeD266

Ok, guys. This is one of those PITA "it's making this noise" posts... bear with me.

1999 ext cab 4x4 5.3L 249k miles.

Had new tires put on in the last 30 days. Problem began 3 days ago.

"Grinding" noise like a wheel bearing gone. Seems to be coming from left front. Haven't had a chance to get it off the ground to examine yet. Bearing was replaced within the last two years. Noise remains when rolling straight and turning left. Goes away when turning right.

Noise doesn't increase/decrease with braking at all.

Also having intermittent issues with ABS activating at low speed - especially on left turns.

Would a wheel bearing - even a low end after market - go this soon? Or should I consider CV joint issues in this mix?

with the quality of replacement parts today this is no surprise of a repeat failure...check out that the parts used are not from china...I just did some U joints and I found many to say,, stay away from the chinese parts...


the abs acting up with the noise and it is the front left driver side this is usually the wheel bearing ..for some reason the driverside bearing fails ...

[old_master]

It could be either side causing the noise. Each 4X4 front wheel bearing assembly has two sets of ball bearings inside, an inner and an outer. On a left turn: The left inner and right outer bearings are loaded and the left outer and right inner are unloaded. On a right turn, the load changes and the oposite ocurrs. If the noise goes away turning right, either the left inner or right outer bearing is bad. Raise the front wheels and check for looseness or noises when rotating the wheel by hand. A stethoscope comes in real handy for listening to the bearing. Camber being out of spec will shorten the life of wheel bearings. Might want to have the wheel alignment checked if it's the same bearing you replaced before.

[MikeD266]

Well now you're just bugging me OM... Good points, though....

Forgot to mention that I DID have a 4 whl alignment done when the tires were mounted. Was significantly out in the front. Maybe I just wore the bearing out because it was so far out for so long... Guess I'll get it up on a jack and wiggle... And I do have a stethoscope around here somewhere... As soon as it stops raining...

[old_master]

Gee, I really hate to bug ya But, did the alignment shop tell you they did a 4 wheel alignment? If they did, they're jerkin' your chain. The rear wheels are not adjustable on your Silverado.

Whenever you have an alignment, tell the tech to set camber as close as possible to zero degrees. It puts the wheel perfect vertical and distributes the weight evenly between the inner and outer bearings. It also makes the tires last longer too.

From under the vehicle, stick the probe of your stethoscope against the knuckle as close as possible to the hub. Have an assistant rotate the wheel slowly, you'll find the bad bearing right away. Keep us posted.

[MikeD266]

Now you're just making it worse OM...

According to the shop:
Before alignment
LF 0.2 camber/4.0 caster/0.66 toe
RF -0.9/1.0/-0.19
Total toe 0.47
Steer ahead 0.42

LR -0.1 camber 0.27 toe
RR -0.7 camber -0.09 toe
Total toe 0.18
Thrust angle 0.18

After:
LF 0.3 camber/3.9 caster/0.06 toe
RF 0.4/4.0/0.04
Total toe 0.10
Steer ahead 0.01

LR -0.1 camber/0.26 toe
RF -0.8/-0.05
Total toe 0.21
Thrust angle 0.16

Based on what you've stated, OM, is there any good reason why the LR lives so far out on toe? Any chance it's somehow compensation for my 200+# of arse?

[j cAT]

Originally Posted by MikeD266

Well now you're just bugging me OM... Good points, though....

Forgot to mention that I DID have a 4 whl alignment done when the tires were mounted. Was significantly out in the front. Maybe I just wore the bearing out because it was so far out for so long... Guess I'll get it up on a jack and wiggle... And I do have a stethoscope around here somewhere... As soon as it stops raining...

these tire / alignment shops are to be avoided..too many owners have problems with these low payed unqualified alignment tire installers working on your vehicle ..

I do my own alignment on my truck.. the last time I aligned it was when I had to replace the inner tie rod..that was several years ago..

I had to align the truck when new because the camber was way off ...too much camber...after the 1000mi breakin I adjusted the torsion bars for correct height then aligned the front end.... min toe and no camber...got 90,ooomi on the original truck tires LT245 firestone...

when the alignment changes that means somethings broke !
these people are not the one's to work on your vehicle..

[MikeD266]

Hmmm...Never even thought to tackle my own alignment, jc. How difficult/specialized is it?

[old_master]

The way it was set before the alignment, you could expect the vehicle to pull pretty serious to the right. The inboard edge of right front tire to wear smoothly and quicker than the left front. And a jagged wear pattern on the outboard edges of both front tires. Is my crystal ball working?

Front camber at .03 & .04 is a bit much, but acceptable. Front toe at .10 is also a bit much, but acceptable. Expect to see/feel wear on the outside edges of both front tires in less than 1,000 miles. Run the palm of your hand, in both directions, along the circumference of the tires and you'll feel a slight jagged edge caused by the toe, and worn more, but smooth, from the camber. It depends how fussy you are when it comes to replacing tires. .00 camber and a maximum of .05 toe would be ideal. Caster is a "handling" or "control" angle and does not cause tire wear, it WILL cause a pull or drift. You're basically looking for no more than .25 degrees difference side to side, and you're fine there.

Rear wheels: If the rear axle tubes, (not axle shafts) are straight, and aligned properly to the differential, and the rear axle assembly is installed square in the vehicle, rear camber will be zero, rear toe will be zero, and the thrust angle will be zero. VERY rarely seen when all are perfect.

Left rear camber at -0.1 degrees is acceptable. Left rear toe at 0.26 degrees means the tire is turned 0.26 degrees to the right. I would suspect a bent axle tube, or the tube is not properly aligned in the differential.

Right rear camber at -0.8 degrees is a problem and it will cause the tire to wear smooth on the inboard edge, (the top of the wheel is leaning inboard too far). Toe at -0.05 means the tire is turned .05 degrees to the right... acceptable. Again, I would suspect a bent axle tube, or the tube is not properly aligned in the differential.

Thrust angle is the direction that the rear axle is headed away from the centerline of the vehicle. Rule of thumb: if it's less than .025 positive or negative, the affect on drift or pull is negligible. When the toe problem on the left rear is fixed, thrust angle will come back closer to zero.

Rear total toe: If you add toe from each rear wheel together, it gives you rear total toe. In your case, 0.21 degrees, too much, should be zero.

With both rear wheels headed to the right, (thrust angle) it will cause the vehicle to drift very slightly to the left. Bottom line, when you combine the adjustments on the front wheels and the thrust angle, it should track very nicely now! To the "run of the mill" alignment technician, everything is within specs... ship it down the road! To the perfectionist... not so much. If a tech knows what he's doing, he can make a car track straight down the road with the adjustments so far out of spec you wouldn't believe it! So, just because a vehicle tracks straight down the road and the steering wheel is straight, is no guarantee the alignment is good. Any questions? Just ask.

Alignment is nothing but geometry, complex until you understand it!

[j cAT]

Originally Posted by old_master

The way it was set before the alignment, you could expect the vehicle to pull pretty serious to the right. The inboard edge of right front tire to wear smoothly and quicker than the left front. And a jagged wear pattern on the outboard edges of both front tires. Is my crystal ball working?


Alignment is nothing but geometry, complex until you understand it!

your crystal ball is right on ! the right pull was pretty stong back when this 2000 sil was new...Even at the 1000mi when I did the alignment you could see the wear on the front tires,,,not good...

A little quick check on the tire pressures / alignment is, to place chaulk on the tire tread , then move the vehicle a few feet and inspect how the chaulk wears off on the tire tread...should be evenly worn almost to the outer tire tread...this is only helpful with new tires...

[MikeD266]

Alrighty then... I'm not happy... Experts - thoughts?

Got all set up to throw a new wheel bearing on the LF side today. New hub, puller, etc. Popped the dust cap to break the axle nut loose before yanking the tire - and the damn axle nut is only slightly more than finger tight. Now, I haven't been anywhere near that wheel for anything since I replaced the bearing almost two years ago.

The question I now have:

Is there any - ANY - reason for anything that a tire jockey does, with regard to mounting new sneakers OR an alignment, to loosen an axle nut in any manner, shape or form? Haven't had problem one since replacing the bearing.

Tightened the axle nut back up and, funny thing, all of the grinding noise disappeared. Fortunately, I haven't driven much since this started... Guess I'm going to go back to changing my own tires out. j cAT, OM or anyone else, any suggestions or direction to point me in to bone up on how to do my own alignments?

[j cAT]

the spindle nut should be torqued with a large torque wrench...what was the torque setting ? also I would use medium lock tight on this nut...removal of all lube grease on the threads.....

did the nut look like someone screwed with it ?...

alignments are very do able with out lasers and expensive equiptment..explaining this over the internet would be a bit too much...

so with this nut being loose how is it that they did this alignment , on the vehicle...

I would not be surprised if this person doing the alignment thought that nut adjusted the left front wheel...

these tire jockeys are dangerous...

[old_master]

Originally Posted by MikeD266

.... any suggestions or direction to point me in to bone up on how to do my own alignments?

I've been doing wheel alignments for 36 years on state of the art equipment, and have taught wheel alignment classes for many years. I wouldn't even THINK of doing it without the proper equipment.

[j cAT]

Originally Posted by old_master

I've been doing wheel alignments for 36 years on state of the art equipment, and have taught wheel alignment classes for many years. I wouldn't even THINK of doing it without the proper equipment.

I know what you talking about....I know roofers that wouldn't even think of installing roof shingles with out air powered tools..

using a expensive alignment machine is much faster....but does not guarrantee anything , with the poor workmanship and , unquailfied techs at the controls !

with proper training you could do a very good alignment with a level and dental floss....