Alignment

[Cary and Don]

Any idea as to how much an alignment will cost if you don't need parts?  Does it really make a difference in the handling? We are thinking of getting the 05 Eagle done.  It has nice new suspension and the front end had been rebuilt a few years ago. Don't have any record of it ever being aligned. Trying to find out if it would make a real difference in the handling or just spending money for the fun of it.

Don and Cary

[eagle19952]

What does your tire wear tell you ?
you can measure the toe in pretty easy.
Does the coach wander ?

[sparkplug188]

This is a copy of Dans alignment guide posted on Eagles International:

$400 or $0 if you do it yourself.

http://www.eaglesinternational.net/forum/viewtopic.php?f=5&t=66

Alignment always starts with the drive axle. You want your drive axle aligned with the frame of the coach. We call this the thrust angle. A simple check that you can do is this:

Park your coach straight on a level hard surface.

Drop a plumbob from a common point on each outer most point of the drive axle housing. For instance, you may use one of the bolts that mounts the stabilizer bar to the drive axle housing.

A plumbob is a string with a ball and pointer attached to it.

Let the plumbob hang freely until it stabilizes and do not let it touch the concrete surface below.

After it is stabilized, mark the ground where the pointer is. do this on both sides of the drive axle. Now you have two marks on the ground.

Now take your plumbob to the front center casting between the torsion bars.

Drop the plumbob from the center of this casting and mark the ground.

Next, remove the coach from where it is parked and then take a measurement from each mark at the drive axle to the front center mark. They should be the same measurement. If not, then you know how much you will need to adjust the drive axle.

Adjutment on the drive axle thrust angle is accomplished through the stabilizer bar.

Next you want to align the bogie or tag wheels to the drive axle.

You will need a ten foot straight edge and your tape measure.

Set the straight edge horizontal against the center of the outer drive axle tire with the other end extending forward through the center of the bogie or rearward through the center line of the tag.

While holding the straight edge, have another person measure from the straight edge to the outer walls of the tire on the bogie or tag. Compare the measurements, they should be the same or the measurement on the front should be no more than 1/16" greater than the measurement on the rear. Now you know what your toe setting is on the bogie or tag. It should be Zero to 1/16" toe in.

Camber setting for the bogie or tag can be checked using a level.

Hold the level vertical against the centerline of the wheel. Check the bubble on your level, it should be centered. If not, you will actually have to install a camber gauge on the spindle to get the actual degree setting so you will know how many degrees to adjust it.

Alignment settings on the bogie or tag is done with tapered shims installed between the spindle and fixing arms.

Next you want to check the front end.

Make sure your coach is parked straight.

To check the front end for toe, take a tape measure and measure from the centerline of the tires on the rear of the tires from side to side. Record the measurement.

Now take a measurement from the centerline of the tires on the front of the tires from side to side.

These measurement should be the same or the rear measurement should be no more than 1/16" greater than the front measurement.

Toe is adjusted through the intermediate tube on the steering.

To check for camber, do the same as what you did on the bogie or tag.

These are just quick checks you can do without going to an alignment shop. Make sure you do not have any worn tie rod ends or steering components. Anytime you replace any tie rod ends or any cross pins and bushings, you will need to have the alignment redone.

If you have any questions, don't hesitate to ask as I know this may sound confusing to anyone who is not familiar with the alignment process.

Dan

[TomC]

Especially with Eagles independent front suspension, front alignment is very important. Out of alignment can mean excessive tire wear, shimmying at any speed, squirrelly handling, etc. You should have all axles laser aligned. Will cost in the $3-400 range. But considering you're sitting on $4,000 worth of tires, it is worth it. Good Luck, TomC

[Cary and Don]

The tire wear is even. The problem we are trying to cure is in the steering.  There isn't any slop in the steering wheel. It is over sensitive.  You are always trying to keep it tracking straight.  Every adjustment is a little too much, so you are always working the steering wheel a little. It doesn't pull to one side or the other. We adjusted the suspension last year because it was down almost two inches in the rear from the front.  We ended up lowering the front and raising the rear to level. It does drive better now than before the height adjustment by 100%.

Since all the parts are new we suspect it needs to be aligned.  Any other suggestions welcome.

$300 or $400 is good news.  We had visions of about $1K.

Don and Cary

[shelled]

over sensitive steering is likely because of insufficient front castor.

edward

[Jim Eh.]

Failing all else:

One other item that can cause a steering issue that you are describing is a binding in the steering linkage somewhere. It is commonly referred to as memory steer. Every steering input requires a larger amount of correction to overcome the resistance causing an over correction. With sufficient caster the steering system, without any binding, should return to steer ahead (relatively). Do you find you have to turn the wheel back to center when coming out of a corner or will it do it by itself allowing the wheel to slide thru your hands?

BTW, adjusting the ride height in the manner you posted would decrease the caster.

[DriverGT5]

I'm not sure how it translates in the bus world but a "darty" car is typical of a little toe-in. Ideally you would be pretty close to 0 total toe in the front. As you drive forward your wheels will toe out just a bit from the friction and that will give you a little stability. On cars toe out helps cornering because the inside wheel will be at a tighter radius than the outside wheel but on a bus I doubt that will matter.

Low front caster will negate the centering effect of a vehicle and can also work in a similar way. If I'm not mistaken I think the early Eagle's are known for having very little caster in the front suspension design.

If your toe isn't zero or 1/16" out I would start there and see. I had a quote for aligning the front end here in Charlotte of $175. I've been told off the cuff about $400 for the whole bus.

[Lee Bradley]

Failing all else:

One other item that can cause a steering issue that you are describing is a binding in the steering linkage somewhere. It is commonly referred to as memory steer. Every steering input requires a larger amount of correction to overcome the resistance causing an over correction. With sufficient caster the steering system, without any binding, should return to steer ahead (relatively). Do you find you have to turn the wheel back to center when coming out of a corner or will it do it by itself allowing the wheel to slide thru your hands?

BTW, adjusting the ride height in the manner you posted would decrease the caster.

I was going the same direction; possibly a king pin/ball joint sticking.

[rusty]

Eagles have very little caster ( less than 2 degrees ) and there is no adjustment for caster. Some try to put more shims in the front upper A arm. All this does is put things in a bind.  Be careful not very many alignment shop can or know how to align an eagle. We have had shops say they can until they get under it a say what is that. Do a three axle alignment. If the boogies are not running true it will push the front end around. When I changed to Michelin tires it helped the wandering some.

Wayne

[Cary and Don]

Thanks for the information.  Hadn't thought of the binding, we will check that.  We found a shop that does alignments on Dinas.  They said they are very similar. At least the guy knew what an Eagle was.  Their next available appointment is two weeks out.  So at least they are busy.

Don and Cary

[Jim Eh.]

I'm not sure how it translates in the bus world but a "darty" car is typical of a little toe-in. Ideally you would be pretty close to 0 total toe in the front. As you drive forward your wheels will toe out just a bit from the friction and that will give you a little stability. On cars toe out helps cornering because the inside wheel will be at a tighter radius than the outside wheel but on a bus I doubt that will matter.

Actually it is toe out that will create  a "darty" car (on a rear wheel drive car). It tends to climb the tire ruts that naturally wear in the road surface. Some cars such as front wheel drive or AWD usually have close to zero toe spec due to the "toe-in" caused by engine torque. I race autoslalom and most racers set extra toe out to help with turn in, it gives more oversteer producing quicker turn rates. Helpful on the track but more of a handfull on the city streets.

Tire pressures may affect the steering touchyness as well along with reduced tire wear so be vigilant of the pressures. Check on your pre-trip and somewhere in between if you travel from a cold climate to a warm one.

[wg4t50]

Caster is always a biggie for handling, also handling can be in three areas,
1-Dart & Dive, lack of lube, rusted up parts, caster.
2-Wonder & Weave, worn parts, sloppy parts.
3-Correct weight per wheel position.

BUT do not over look the big issue of weight per tire/axle, since each wheel needs to be adjusted for proper amount of weight, this become a lage issue, know I watched one using 6 portable scales, and mechanic rolling around adjusting all the torsion bars, Not wquick nor easy, then you can get into the alignment.
This was on the older 01 Eagle, What a mess to drive, after all the work it was better, not great but much better. Had been set with way too much on left front and right drive, they seemed to be carrying all the weight, very strange handling.
Clearly, we all have different experiences.
Dave M

[belfert]

The steering on my Dina has very little play yet it doesn't easily go straight down the road.  A car will typically go straight down the road if you hold the steering wheel in one spot.  With my bus the driver has to constantly make tiny corrections or eventually you'll end up in the ditch or in the center median.  I've had the steering gear rebuilt, some bearings in the steering replaced, and had the wheels aligned.  Bryce Gaston knew about the bearings in the steering and did the work for me.  The steering gear made the biggest difference, but it still takes some work to keep it going straight down the road.

[Geoff]

I had the same problem; it turned out to  be worn dogbone bushings in the rear.