Looking for a GREAT alignment shop - Somewhere in ID, WA, OR, WY, MT, ND, SD

[Brian Diehl]

Thank you everyone for your replies.  I have an appointment on the 13th with Dick @ Precision Frame and Alignment http://www.precisionframe.com/.  They believe they can figure out what is wrong and help me get a solution.  I'll update this once I learn what they have to say.

[Brian Diehl]

First of all, the experience I had was very good!  Dick is very knowledgeable about what he does and knows how to educate his customer and bring the customer in on the investigation stage of the alignment work.  It is great to be able to be walking around speaking with him as he is setting things up and checking each axle.  Here is what I learned:

1)  The front axle alignment is just about perfect. 
2)  The drive axle is pointing to the left such that from the drive axle to the front axle the thrust angle is offset by 2"
3)  The tag axle is point to the left such that from the tag axle to the front axle the thrust angle is offset by 3"

This perfectly explains why the bus is always pulling to the right.

The charge to fix the drive and tag axles is $400 should I choose to do it.  Now I just need to decide if I want to have it fixed.

[Sean]

The charge to fix the drive and tag axles is $400 should I choose to do it.  Now I just need to decide if I want to have it fixed.

That's a great price and you will not regret it -- just do it.

You could save that $400 in tire wear alone.

We had a similar drive-axle alignment issue and I'm glad we had it fixed, even though we paid more than that at a Freightliner dealer.  Coach handles much better now and tire wear has dropped significantly.

-Sean
http://OurOdyssey.BlogSpot.com

[Sam 4106]

Hi Brian,
Thanks for the update. I think a lot of us would be interested to know what work would be required to fix the problem. It seems to me that your $400 would be well spent for the sake of driveability and reduced tire wear, but it is easy for me to sit here and spend your money.
Good luck with your decision, Sam MC8

[bevans6]

I would not hesitate for a second.  I vote with the "just do it" crowd.  I just made a similar upgrade in steering performance to my bus, the different in enjoyment is astounding.

Brian

[JohnEd]

Brian,

Welcome to Eugene. Really pleased to hear that Dick resolved your problem.  I wouldn't pass up the chance to have him correct the problem.  Now in the most remote possibility that Dick missed something......he will correct that also.  You pretty much have a guarantee that your problem will be fixed when you leave town.

Can anyone share with us "how do you check the tag and drive alignment?"  How do you adjust it?

Thanks,

John

[rv_safetyman]

JohnEd, Brian went to Elk River, MN and had a different "Dick" work on the alignment (not Dick Kaiser).

I too, would like to know how they adjust the thrust angle. 

I have had on my list of articles to write, an alignment process that the racers use called "stringing the car".  Here you put a tight string along the bus making the string parallel to the side of the bus.  You then measure in from the string to measure thrust angles on the rear axles and tow-in on the front axle.  I have not had time to set up the system to verify it works on a bus and to take pictures.

Jim

[John316]

I wouldn't hesitate for a second. Do it!!!!

You won't regret it. Just do it!!!

God bless,

John

[JohnEd]

Jim,

Thanks for getting back to me and clearing that.

Stringing sounds good.  I asked cause they aligned these pups before Bear Alignment Sytems happened, let alone all the lazer stuff.

Tow is measured by spinning the tire and coating it with quick dry paint.  Then with the tire spinning you rub a sharp ice pick type tool against the painted portion of the tire to scribe a sharply defined line around it.  Using a square leaned up against the tire and carefully placed against ech scribed line you measure the front distance between lines.  Do the same for the rear of the tire and take the difference in the measurements for the tow.  The weight of e vehicle must be on the tire so the jack needs to be under the king pin or other strong structure o the underside.  You can measure the camber with a level and measure the amt that it must be moved to get it perpendicular and with geometry you can compute what that distance needed to correct must be.   You measure at the rim and use that rim diameter and the off vert and use trig to find the angle.  Caster... I got nutt'n.  Sure hope you get this all worked out as it is going to be useful.

John

[gumpy]

Brian,

For $400, I would do it if I had confidence they knew what they were talking about and could fix it properly. I'd probably have them explain the correction procedure first.

Please let us (me) know what you decide and if you do have it fixed, how it goes. I really should get the alignment on mine looked at as I've never had it done. Mine drives
pretty well, but lately seems to require more correction. Could be the larger tires I just moved to the tag from the steer. They were cupped and worn on one side (which is
why I think I should get the alignment checked).

craig

[rv_safetyman]

JohnEd, the toe-in method you mention has worked well for smaller vehicles as far as I can tell.  However, the reading I have done suggest that you need to drive the bus a few feet forward to get all of the clearances "organized" the way they would be going down the road.  I think that just jacking up the wheel and then dropping it down could give you some false readings.  

I made a bar out of electrical tubing with a nut welded on each end.  I thread in some thread-rod into each nut.    I then drive the bus forward on the shop floor several feet and carefully place the rod in front of the suspension and tighten the thread-rod so that the bar is gently seated on a very specific place on the tire.  Then I move to the back of the suspension and place the rod against the same place on the tire.  There should be about a 1/16 to 1/8 clearance on the rod.  I have aluminum wheels, so rim run-out is minimal.  I have repeated the process with the tires rotated to a different location and get reasonable repeatability.  I have a very old alignment set (mostly bought for the turn-tables) and it used the rod method.  Worked fine for the older cars.

I have used that method on a bunch of cars and the bus.  The bus handles very well and tire wear is normal.  

Many "vintage" race folks use the string method to adjust toe in.  My plan is to string the bus and check the toe-in by measuring off the string on each side (will take a bit of simple math to take four measurements into consideration since the wheels will not be perfectly straight) and compare it to the rod measurement.

The use of a level will indeed give you a measure of camber.  At least it will tell you if it is reasonable.  Caster is a value that we can't measure with simple tools.  I have a fairly modern set of camber/caster gauges and turn tables for cars, but would not attempt to try to adapt them to the bus.

As home mechanics, we can fairly easily adjust toe-in. Anything else should be left to the experts.

Jim

[JohnEd]

I have increased the tow-in till I got a stable ride on the freeway.  Of course the shop had already set to the "correct" position.  I agree that you need to roll the vehicle after setting it back down but that applies only to the way it was raised.  If you lift from the king pin bottom point the suspension comes down "relaxed".  If you lifted by the frame then when it sits down your wheel and suspension will be in a bind and you need to roll the vehicle to "relax" that binding.

When I had a low floor jack I didn't bother with rolling. If I had to use a tall jack I rolled the car or the readings were crap.

I hope you get that set of instructions done and printed for all of us.  Even if there is onlyone method described and it can be followed by all then this problem will be solved.  I think that effort needs to include some data on verification of the condition of bushings, bearings, Kings, etc.  Stuff that you need to do BEFORE you start twisting bolts in a suspension alignment effort.

Jim, good luck with this.

John

[bevans6]

"Stringing" a race car is used up to quite high levels of racing, and is certainly used by pro teams all the time.  It starts with a flat surface to put the car on, adjustable platforms are used in the field and are levelled with laser systems, or with beams and machinist's levels to within .010" to .020".  Each car will have a custom rig made for it that fits into the chassis with index pins for repeatability.  The string is high tension test fishing line, about .020" in diameter.  The line forms a perfect rectangle to a machined accuracy of a few thou. around the car, and you measure to the wheel rims if you are in a hurry, or to machined setup plates if you are trying hard.  Wheel rims aren't really all that accurate, a good rim will have ten or twenty thou run-out.  You measure from the edge of the string to the rim or plate using a digital caliper, and you can get accuracy down to a couple of thou if you are good.  All this sets the the width of the car and the toe.  Digital levels or protractors are used to set castor (on machined surfaces on the uprights, usually) and camber, and digital gauges are used to set ride height.  Your setup platform also includes digital scales that allow you to measure each wheel load to the pound.

When I had my bus aligned with a two axle Hunter laser setup,  they basically created the box with lasers attached to each wheel.   They measured the alignment of the drive axle to the steer, measured toe, castor and camber with levels, but I did not notice them doing any measurements to measure offset of the axles in the chassis.  But in general the process they used on the bus and the process I use on a race car were really very similar, just different tools to accomplish  the same goals.

Brian

[rv_safetyman]

Brian, I was hoping you would jump in.  Most of my experience has been in the vintage car area, but I had a suspicion that it was used on other levels of racing.  Done properly (as noted in your post), it should apply to any vehicle. 

I want to do the process to make sure it scales up to a bus.  I am concerned about getting 40 plus feet of string tight enough to make meaningful measurements.  The thought of using fishing line makes good sense.  The lighter weight should minimize the catenary affect over that large distance.  The good part of the process is that the long side length of the bus will make a good reference.

One of the main reasons I want to string my Eagle is the fact that the bogeys can get out of alignment and I want to check that.  On an Eagle, the alignment (at least reasonable adjustments) can be done with shims.

My opinion is that alignment of our buses does not have to be done down to the thousandths.  A race car needs that level of accuracy. 

Guess I had better get on with trying the process and documenting it

Jim

[luvrbus]

Jim, I used the 20 dollar laser from HD or Lowes to check mine pretty good little gadget for checking the boogie also

good luck