Wheel/Tire Balance questions

[TruckerChris]

Running down the highway any faster than 60mph I get a good dose of steering wheel shimmy and the truck shakes a bunch. It does it on and off the throttle and hitting some of those bigger holes in the road seem to jerk the wheel more than any other truck I've driven. Today I stopped at a Tire Shop in Shreveport, LA and had them take off my centramatic's on the steers and then balance the tires and mount them back up.

This shop seemed to be anti-centramatic's and said they haven't seen a set last longer than 100k... I don't know if I believe that but after I started driving down the road the shaking was almost gone. It's a lot better than before but it still shakes and shimmy's while at cruising speed. The steers are in great condition and are wearing evenly. The PSI is spot on too...

What do I do now? I'm thinking of calling up centramatic and seeing what they have to say. What about an Alignment?

Chris

[klleetrucking]

.1 get to an alignment shop and have the front end checked out. A good shop will evaluate the problems and tell you whats worn out.
.2 I have had Centrimatics on my steers for over 100k and I'm happy with them. BUT, my tires were balanced before the Centrimatics.. Are they a magic cure? NO
.3 a tire man will point at the suspension, a suspension man will point to the tire.
.4 Good luck. A front tire shimmy/bounce will wear you out!

[Rev.Vassago]

.3 a tire man will point at the suspension, a suspension man will point to the tire.

That's the truth.

This shop seemed to be anti-centramatic's and said they haven't seen a set last longer than 100k...

I got 132,000 out of my last steers. I put Centramatics on at about 60,000 miles, when I had a bad shock start to cause uneven wear. Even with the uneven wear, I managed to get a good life out of the tire. The steers I have on now are at 60,000 miles, and still look brand new. Whether or not the Centramatics are the cause is unknown, but I believe they play a part.

If you had a suspension issue, you'd likely see uneven wear. It wouldn't hurt to have your suspension looked at by a reputable shop, however. It should be pretty easy to see if there is an issue just by a visual check (look for oil stains on the shock). You might want to have your kingpins looked at too, however if that were an issue, you'd probably hear popping noises while turning sharply.

If you pull the same trailer all the time, you might also want to invest in a whole truck alignment.

[TK THE TRUCKER]

Did you buy your own truck or something Chris or is it your company truck ? 8) 8)

[Doghouse]

You have some worn suspension parts on there. You shoud feel no skake/shimmy at any speed. Some trucks react diff. when you hit bumps, some are heavier on the steers than others, so just because other trucks don't do what you one does now really doesn't mean anything. Have your truck looked at by a suspensin professional, preferably the trucks manufacturer.

[no_worries]

When they put your tires on the spin-balancer, did they check for an out-of-round condition? Vibration due to out-of-round can show up at various speeds depending on the particular harmonic characteristics of your truck. There won't necessarily be any wear indicators and getting the tires balanced will improve the condition...for awhile.

[Doghouse]

I forgot about out of round, that could be a problem also. I've seen trucks pass me and their wheel visibly wobbles,..gotta drive a guy crazy.

[lwsii]

You've probably fixed it by now, but you mentioned shreveport, so you're not far from the 589 exit south side (In Longview), I forgot the name, but they are in miracle workers. I can't express how impressed I was, they absolutely know their **** & and they do it all-tires, suspension,alignment, because like he told me, its a system, it all works off each other; in their view it would be wasting their time & my money if all they did was mount & balance (and check the trueness or actual how round is the mounted tire) & then send me somewhere else to make sure they went down the road in a straight line or had a driveline/suspension angle wrong to fix somewhere else down the road. them & equalizers (or cat-eyes) was the best money I ever spent.

[INKTOXICATED]

my truck had a bad shimmy at 45-50 mph then it slowly got better after that. the mechanic took the steers off and put some little gauge to the tread and spun the wheel. then found high spots or something. he took the wheel off and put it back on according to his chalk markings and wah-lah. the shimmy was nearly gone. these were less then 10k mile tires too. he said that there getting brand new trucks and tires in with shimmy. jersey roads are tearing **** up. not onlt do i hate the shimmy i hate when the steering wheel is crooked!!!

[Larry227]

If you're getting a steering wheel shake at 60 or so it's most likely a steer tire too far out of round. No tire is perfectly round but when one gets above 60 thousandths it will cause a shake. Sometimes balancing will help but if you can get it below 60 thousandths you don't need to balance. Only way to check is with a radial runout gauge. If it's only a little out sometimes you can jack it up and loosen the nuts (if it's unimount) with the high spot on top and let it settle on the hub. If that doesn't bring it below specs you have to break the bead and move the tire on the rim or try a different tire. It's called match mounting. When done right there's never a need for balancing or any type of add on balance device. That's what INKTOXICATED mentioned.

This isn't to say you shouldn't check out your front end. That should be the first thing you do. But when you have it jacked up slowly spin the steers and see if they stop smoothly or stop and roll in the other direction a bit. If they stop and roll in the other direction it's pretty far out of round. If they start rolling as soon as you jack it up then it's severe radial runout and you've found a problem for sure.

[heavyhaulerss]

I know nothing about tires. I do know that when I had bad trailer tires the truck would bounce & shake at certain speeds. put new tires on tailer & the truck rode like a new one. I never thought the trailer could make suck a difference in the way the truck rode.