Tires Vibrate At Low Speeds...

[bob h]

Well I went back to the T.A. where I had the new tires installed. I advised them of the problem and they said they would check it out. A different Tech. said the tires were not balanced properly in the first place and he would correct it. So after spin balancing them he adds and changes where the wheel weights are located on the tires, then he switched sides with tire/rim. He mentioned that my one rim was a little out of whack. He added 12 weights to one, and 8 to the other. He said this should work fine. He also advised me the on one wheel 4 lugs were loose, and the other wheel had 2 lugs loose from the guy who changed the tires before, apparently he never tightened them properly. Then I asked if they were torqued, and he said they don't have a torque wrench, as he's been trying to have the T.A. buy one.

I was in a hurry as I was under a load and needed to move quickly. I did not get to take it for a test drive. So I left. Well I get down the road and low and behold the shack and shimmy is still there at about 30 mph. It appears that nothing has changed at all. As indicated before with the old tires there was never any shake or shimmy... none.

So today I’m heading back down to the T.A. again to have this check out.
Any tips or suggestions?

Thanks.

Are the tires running true (is it wobbling side to side or bouncing up and down)? You need to look at this yourself, the techs will ignore it.

What do you mean by "spin-balancing"... on or off the vehicle?

An egg-shaped tire will balance, but the heavy side will cause it to "tramp" or slap the road as it spins under a load.

Tell them sternly; "There was no shaking before the tire replacement... why is it shaking now?!?"

If you want to verify the alignment - - place a protractor or angle finder...

http://images.google.ca/imgres?imgur...lr%3D%26sa%3DN

...on the flat part of the axle just beside the springs/u-bolts... then, post what you find.

Make sure you come back and post the outcome when you get the problem solved.

[Neckster]

Here's what happened... The mech. at the T.A. checked my front end out and said that my kingpins were bad, specially the passenger side. He said it had about an inch of free play and this could be the problem.

He suggested I take it down the road to a big-truck garage, which I did not know was even there. Supposedly I have to wait until Monday when this tech. comes back to work. Then he will look at it again.

Ok, so I head down the road to the big-truck garage to have a certified mech. look at it and give me his written opinion on the front end.

After $81.00 for an hours worth of work, here's his opinion and suggestions, and what he found.

This is a top notch mechanic with 28 years of experience and no beating around the bush!

1. There is nothing wrong with the kingpins
2. There is nothing wrong with the front end parts at all, everything is tight
3. Wheel bearings are in good shape
4. Shocks are all good
5. Springs are all good
6. Steering parts are all good
7. Wheel alignment ok, he checked the old fashion way.
----------------
He did find one wheel bearing slightly loose and tightened it to spec.
He indicated the problem is the TIRES period! The tires are either bad from the factory, or they are not balanced properly. He also said that there could be a rim out of whack due to not being torqued and/or the lugs being loose, but he would put money on the tires being bad or not balanced properly.

He could not believe that the TA never torque the lugs, and doesn’t even own a torque wrench.

I'll keep you posted as to the out come.

Thanks!

[COLT]

If a tire is cupping, wearing uneven, something is wrong, period. Worn front end parts, toe in, soft springs, (ride height) shocks, something could be bent, but still tight. A simple (old fashioned ) toe in check, means nothing. Rear suspension problems can cause front tire wear. The last tires were replaced because of uneven tire wear, new tires go on, IS the original problem fixed? A bad drive tire can cause vibration, that seems to come from the front. Dose the vibration get better with a load on ?

[Neckster]

I was told that the cupping of the tire was mainly from either over inflation or under inflation. I was also told that if the lugs were not torqued and were loose this could cause the holes to become egg shaped and this could be part of the problem.

Whatever the problem is, it's very annoying to drive a truck like this, especially at around 30 mph, as this speed is used most of the time within cities.

Also remember THIS DID NOT HAPPEN WITH THE OLD TIRES, maybe I should have left the old tires on.

My suggestion would be to put a used tire on one side without balancing it first, if that don't work try to balance it and put it back on. Or maybe another rim and tire from the rear, or another known good rim and tire.

I’ve already put over 1,000 miles on the tires.

[COLT]

Over inflation will wear the center, under inflation will wear the outside edges, egg shaped lug holes ? Well that would not be good! Something cupped your last set of tires.

[JAXLE67]

Lots of times many tire guys wont put the tire lube on when the mount the tires causing the bead not to pop out evenly leaving u with a out of round condition that will shake no matter who or how its balanced. It could be just out of round period. The worst out of round bald junkiest tire can be balanced but if it doesnt roll round then its gonna bounce. my advice is go to a real truck shop that can spin them up on the truck then u can see whats up

[Krzysztof]

Common misconception. If they were torqued right the first time, they do not ever need to be retorqued. Shops just tell you this to cover their ass!

As a former mechanic on Cars, Pickups, and Semi's I have to dispute this on one front. Steel wheels you're correct, however on Aluminum wheels the metal will actually stretch when the lug is tightened (stretch as in accomdate the lugnut not making the lug fit the hole properly). So you DO need to re-tighten them after 50-100 miles to make sure they're all still tight. After that recheck unless you take the wheel off again they're good to go.

[bob h]

Common misconception. If they were torqued right the first time, they do not ever need to be retorqued. Shops just tell you this to cover their ass!

As a former mechanic on Cars, Pickups, and Semi's I have to dispute this on one front. Steel wheels you're correct, however on Aluminum wheels the metal will actually stretch when the lug is tightened (stretch as in accomdate the lugnut not making the lug fit the hole properly). So you DO need to re-tighten them after 50-100 miles to make sure they're all still tight. After that recheck unless you take the wheel off again they're good to go.

'sup?

I disagree. Steel wheels will settle-in as well, following the initial torque.

If this re-torquing concept was a major undertaking, I could see reason for argument, most shops will probably do this re-torque for free... where's the issue?

[allan5oh]

I don't know, I used to do the re-torque all the time. Problem is was I was running nights, and it was a PITA. Every single time, the nuts didn't budge.

All the failures I've seen(some MUCH less then 50 miles) have been due to the initial torque being wrong. Torquing isn't the only issue either.

[yoopr]

I was told that the cupping of the tire was mainly from either over inflation or under inflation. I was also told that if the lugs were not torqued and were loose this could cause the holes to become egg shaped and this could be part of the problem.

Whatever the problem is, it's very annoying to drive a truck like this, especially at around 30 mph, as this speed is used most of the time within cities.

Also remember THIS DID NOT HAPPEN WITH THE OLD TIRES, maybe I should have left the old tires on.

My suggestion would be to put a used tire on one side without balancing it first, if that don't work try to balance it and put it back on. Or maybe another rim and tire from the rear, or another known good rim and tire.

I’ve already put over 1,000 miles on the tires.

Just because the tires are brand new it doesn't mean that they can't be defective right off of the Line.
I had this happen a couple of times.

[Papa Rick]

I had this problem after buying 8 new drive tires. I had some vibration with the old tires, but nothing compared to the new ones. My problem was found by a mechanic from a different garage, in that I had two wheel (steel) that were out of round.

Once I got two new steel wheels, the vibration was gone.

I learned the importance of watching when you buy tires and get them balanced, to be physical there and watch it happen.

The reason I say this, is because when I took it to another mechanic and saw the tire go on the spin balance, I noticed the wheel out of round before he ever said anything.

Another thing I have noticed, is the smaller garages, will usually let you watch them doing work, and ask questions.

I always ask if it is ok to ask questions because I just want to learn how to do some things. They have all said it was fine, except for the big chain Truck Repair Centers. (For Insurance purposes you are not allowed)

[bob h]

Just because the tires are brand new it doesn't mean that they can't be defective right off of the Line.
I had this happen a couple of times.

Ditto, I've seen this several times as well.

[bob h]

I don't know, I used to do the re-torque all the time. Problem is was I was running nights, and it was a PITA. Every single time, the nuts didn't budge.

All the failures I've seen(some MUCH less then 50 miles) have been due to the initial torque being wrong. Torquing isn't the only issue either.

How could it be a PITA? You only need to do this once following the initial install... unless, of course, you were with one of those companies that torque them on a regular basis... that quickly becomes pointless btdt.

I agree... initial torque, or lack thereof, is the major issue... keeping in mind that over-torquing causes many failures as well (ye ole 1" impact gun!). Also, proper wheel bearing adjustment procedures (or lack of that as well).