Truck Jerks from side to side?

[Papa Rick]

Need some advice on this one. 2003 C-15 W900L Daycab. I have a jerk in my Truck that goes from side to side when the speed is 40 to 45 and 66 to 69 mph. Otherwise it is a smooth ride.

I have noticed that it does it much more when empty than loaded. I can notice it when loaded, but nothing like when I am empty?

I have had trucks that had bounces in them, but never a jerk from side to side (left to right, and right to left)

I had this in it prior to my wreck an everything was checked and fixed from the wreck, but it is getting worse.

Kingpins replaced after the wreck, no change

3 axle alignment done after wreck, no change

I replaced the steer tires, had them spin balanced on the drum and nothing changed.

Replaced the drive tires and nothing changed.

Had suspension updated 18,000 miles back, no change.

Front shocks replaced 75,000 miles back

Rear shocks replaced 45,000 back

My truck has 859,000, so started replacing items as needed, but nothing has caused it to get any better, or worse.

Could it be cause by a bad brake drum? No reason to think this just thinking out loud?

Or maybe the shock on the back of the cab, or thrust bushing (this is what I call it) that goes from left to right behind the air bags and shock on rear of my cab.

Thought maybe my tires would start to show some funny tire wear as I have 10,000 on them, but nothing yet?

Any advice for me to check would be so appreciated.

[9200IH]

Papa Rick I know you said you had a 3 axle done on your truck but if I were you I would spend some time with a couple tape measures, a string and a buddy.

Your drives need to be square to the frame, parrallel with each other, centered with the frame, the same distance from steer to front drive from side to side.

Mike

[NotSteve]

You need a 400 pound APU to counteract the side to side action.

[Papa Rick]

Done did the string, tape and buddy and found nothing out of measure. I thought for sure by now if it was something like that or anything that I don't know to check it would have showed up on my tires by now????

Really at a loss of what to check for.

[NotSteve]

Motor mounts?

[Rev.Vassago]

Replace the steering wheel with one that doesn't jerk from side to side.


All kidding aside, given the fact that you've already checked or replaced everything else, I would look at the steering - specifically the steering box. Perhaps if there is too much free play in it, you are noticing it at certain speeds. After all - you've already replaced everything else. Why not the steering too?

[wot i life]

Truck jerks from side to side badly until you`re empty?
That is to say until you have "unloaded"?
Would there be a box of Kleenex in the cab at the time?








Sorry

[Maniac]

If you have the AG 200 rear suspension, the bushings between the rears are probably worn out.

AG 200 was famous for this and there have been several fixes over the years, check with KW and find out how to check the bushings and what to look for.

AG 200 is the one with the 1" air lines that go thru the frame from inside to the bags.

[Papa Rick]

Going to see if the KW place in Chattanooga can look at it tommorow. As for the suspension, I had it updated and all bushings that should be replaced done 18,000 miles ago.

When this started I thought it was cause the tires were getting wore out and it would go away when I replaced them, but it has not.

Really it seems to be getting worse as times go by.

[Jumbo]

Motor mounts?

Or transmission mounts? Or like rev said steering box valve.

[Papa Rick]

Went to KW Dealership in Chattanooga TN, and had the following done, which fixed 95% of the problem.

On the drive axles, replaced all wheel bearings, inner and outer, races, brake shoes, and drums. Shoes and drums were not the problem, but were in need of replacing.

When I took it up there, the shop foreman rode with me and when we came back he put the truck up on jacks and had me get it up to the speed that it was doing the jerking.

Then he took the axle out of the one he thought was causing the problem and you could see silver in the fluid and the wheel was loose. (I learned something new here, because I had always seen mechanics just jack the truck up and take a pry bar and check for looseness) Which was what he did, but then he told me he would show me how to check even better on this.

3 out of 4 had silver in the fluid in them, so I had them change all out since truck had 859,000 on it and not sure when if ever it had been done prior to me buying it.

After pulling the bearings out you could see where they were scratched up and needing to be replaced.

I learned something here because I always thought that if the bearings were going bad you would have tread wear showing it different, but not mine.

He told me to check the fluid in the axle and look for the silver would be one of the best ways to check and if in doubt pull the axle out and you could really see.

[heavyhaulerss]

thank you PAPA RICK . FOR SHARING IMPORTANT INFO

[allan5oh]

Wheel bearings will not show up as tread wear, unless they're really bad read to blow. Actually you'll probably have a wheel seal leak before that happens.

Wheel bearings are very precise.

[Bandit102]

I'm thinking spring bushings in the front end.

[bob h]

Rick, I've got a little trouble with your description of the problem; Is this a cyclic jerking... like a wobble? Or, does it occassionally dart in one direction or the other?

Do you feel this in the steering wheel? Or, more in the cab/seat of the vehicle?

[Papa Rick]

HECK!!!!! Thought the wobble was gone, and was thinking it would get better, but no chance of that. Everything I have had done so far has not fazed it at all.

I posted that it fixed 95% of the problem, but what happened was I was on a bumpy road when I came and posted that it was fixed. Got on a smooth road, and WHAM there it was again.

It has always pulled to the right some after the wreck, and I took it back to KW in Chattanooga and they said everything looked fine, adjusted to toe in to try and correct the problem, but it has not helped at all.

The truck still pulls to the right. The only tire wear is on the right tire on the outside it is starting to wear more. It has the wear marks on it, and they started out with 5 slits on them. The left tire has 5 on the out side, 3 on the inside, the right tire has 3 on the inside, but only 1 for the outside???

I checked the tread depth on the drives , and all the same, no wear patterns on them at all.

I cannot tell if it is coming from the front or rear. I do not feel it in the steering wheel, but the front end gets to bouncing when this is doing this.

I have looked and checked the shocks, no leakage, and after driving it they are warm.

The leaf spring bushings are all ok. The right spring and both kingpins were replaced when it was wrecked.

The tires have 16,000 miles on them and look good except for the wear on the right outside tire.

Any suggestions on this? I have a run to go by the KW place tommorow and will take it by there for them to check again????????

[allan5oh]

I cannot tell if it is coming from the front or rear. I do not feel it in the steering wheel, but the front end gets to bouncing when this is doing this.

That to me indicates a tire problem, they may need to be remounted/balanced.

But "pulling" is usually alignment of the drive axles.

[bob h]

Thanks Rick... much better description

quote="Papa Rick"]HECK!!!!! Thought the wobble was gone, and was thinking it would get better, but no chance of that. Everything I have had done so far has not fazed it at all.

I posted that it fixed 95% of the problem, but what happened was I was on a bumpy road when I came and posted that it was fixed. Got on a smooth road, and WHAM there it was again.

It has always pulled to the right some after the wreck, and I took it back to KW in Chattanooga and they said everything looked fine, adjusted to toe in to try and correct the problem, but it has not helped at all.


Toe-in does not cause vibration, wobble, or pull

The truck still pulls to the right. The only tire wear is on the right tire on the outside it is starting to wear more.

The steer axle likely had excessive toe-in (before they adjusted it) which caused the outside wear on the passenger side steer tire... that resulting (and continuing) tire wear might be the cause of "pulls to the ditch", i.e. - separated or broken belts. You can verify this by swapping the wheel/tire assemblies from on side of the vehicle to the other; if the pull goes away or changes direction, you've found your pull problem... however, if there is no change, then radial tire pull is not the PULL problem

It has the wear marks on it, and they started out with 5 slits on them. The left tire has 5 on the out side, 3 on the inside, the right tire has 3 on the inside, but only 1 for the outside???

NS... WTH??

I checked the tread depth on the drives , and all the same, no wear patterns on them at all.

If the tractor IS dog-tracking, the wear might not show up at all on the drives... but, on the steers (the steer tires will correct the improper thrust angle of the drives)


I cannot tell if it is coming from the front or rear. I do not feel it in the steering wheel, but the front end gets to bouncing when this is doing this.

THAT sounds like too high of a caster angle on the steer axle... did they give you an alignment printout? can you get me those #s? Between the steer axle and the springs, there is usually a "wedge-shaped" spacer... take a look and see if there is one on each side; same size, direction facing, etc..

I have looked and checked the shocks, no leakage, and after driving it they are warm.

The leaf spring bushings are all ok. The right spring and both kingpins were replaced when it was wrecked.

The tires have 16,000 miles on them and look good except for the wear on the right outside tire.

Any suggestions on this? I have a run to go by the KW place tommorow and will take it by there for them to check again????????[/quote]

[Papa Rick]

It has the wear marks on it, and they started out with 5 slits on them. The left tire has 5 on the out side, 3 on the inside, the right tire has 3 on the inside, but only 1 for the outside???

NS... WTH??

It has what people call wear indicators that you can look at and see if one side is wearing faster than the other. I believe this is what they are called, not sure.

THAT sounds like too high of a caster angle on the steer axle... did they give you an alignment printout? can you get me those #s? Between the steer axle and the springs, there is usually a "wedge-shaped" spacer... take a look and see if there is one on each side; same size, direction facing, etc..

BEFORE THEY RECHECKED IT AND READJUSTED IT:
This is done using the Josam Report

Left: Right:

Camber +030 Camber +0 5
Caster +045 Caster +0 0

Total Toe +1.1

On the tires the left one shows straight up +0.0
Right one shows +1.1

After the Readjustment

Camber and Caster show the same, total toe went from +1.1 to 1.6

Left tire still shows straight up at +0.0
Right tire now shows 1.6

According to the picture I am looking at the right tire was set to lean in a little to start with, and on the readjust, it was set to lean in (to the left) even more.

These were not used tires that were on the truck after the accident, but new steer tires mounted in the body shop.

I did not go by the KW shop as I had many things to get done today and ran out of time.

Advice and suggestions needed!

Thanks

[tracer]

Going to see if the KW place in Chattanooga can look at it tommorow. As for the suspension, I had it updated and all bushings that should be replaced done 18,000 miles ago. Really it seems to be getting worse as times go by.

One thing that might help is this:

1) drain all fluid from the power steering system
2) fill to capacity with POWER-STEERING FLUID (not engine oil)
3) bleed the air from the system

I just did it on my truck and steering has considerably improved. Evidently a lot of shops/mechanics use ENGINE OIL instead of POWER STEERING FLUID when topping the reservoir!

Also, you might have air in the system and that causes "shimmying and oscillation" while driving, according to my International truck manual.