99 Montana Alignment Problem

[blockhead]

I just got new tires on my Montana and the tire place said that the camber on the left front wheel was -2.0 degrees (should be -1.2 to -0.2) and the right front was at 0.1 degrees. They said the only way to correct this was to get camber bolts and redo the alignment. I thought camber was usually only messed up if you've changed the ride height from the original factory height (which I haven't). Anyone have any idea if I'm being told the straight story on these camber bolts and if so how hard is it to do. In other words how much should I expect to pay for this? It's always something whenever I've taken my vehicle to a tire place to get tires. All thoughts/comments are welcome.

[463]

trust the mech,shop,shop service writer and last is your gut feeling. i go to my GM dealer for all the alignment work and have had many conversations over the years. Note i get the alignment printout with the before and after alignment information and keep it in the auto for next time it goes for a alignment.

[1999montana]

Originally Posted by blockhead

... I thought camber was usually only messed up if you've changed the ride height from the original factory height (which I haven't)...

The only things I know of that will change the Camber, Caster or Toe angles are hitting potholes, curbs or replacing worn components.

While doing repairs will disturb the adjustments made when the vehicle was new or last had an alignment, worn components ignored and not maintained can have the same effect.

For instance, worn ball joints will change the camber angle as will worn lower control arm bushings. I just replaced the lower control arms on our van last year. Before that, I replaced the lower ball joints only to replace the entire assembly a short time later.

I tried to give the front end as much positive caster as I could when re-connecting the shocks to the knuckles (there is a small amount of play in the holes in the strut and the bolts will shift ever so slightly.

The upper shock mount attached to the shock forms the pivot point for the center line of the steering knuckle. If the mount is worn, it will throw the camber and possibly even the caster angle off enough to be noticed during an alignment.

Bear in mind also that as the lower control arm bushings wear, the distance between the center line of the pivot point of the lower arm and the center line of the ball joint will change. This will affect camber too.

It will also affect toe adjustment and make it nearly impossible for the front end shop to do a proper alignment.

Tightening up the front end by replacing worn components is the only way to get a reasonable alignment.

This link does a pretty good job of explaining the relationship between Camber, Caster and Toe: http://autorepair.about.com/cs/gener.../aa012201a.htm

[blockhead]

Thanks for the info. Do you have any idea where to get the information on what is involved in putting in camber bolts?

[1999montana]

Originally Posted by blockhead

Thanks for the info. Do you have any idea where to get the information on what is involved in putting in camber bolts?

No idea.

As a matter of fact, while I did notice that the original bolts have a spline on them to prevent them from twisting, I didn't even take that close of a look at them to see if they were already camber adjusting bolts or not.

I believe if they are not, the ones the tech would install would pass through the shock and into the knuckle that houses the hub bearing and axle assembly.

My guess is the bolts the tech wants to use are designed with a slight eccentric shape that allows him to twist the bolt to a desired angle in order to position the knuckle (and the angle of the axle center in relationship to the road plain) to the correct angle.

[1999montana]

Originally Posted by blockhead

Thanks for the info. Do you have any idea where to get the information on what is involved in putting in camber bolts?

Here's another link that defines the relationships between camber, caster and toe adjustment quite well: http://www.aligncraft.com/terms/term...Front%20camber

[rcnewbeh]

hello there
sorry about the spelling its not my greatest
buy the way those numbers look the side to side differene is
just over 2 degrees the right side is to high left is to low
did you have a tranny job done ?
because they will loosen the craddle bolts and change the camaber easly and caster
if i had the car on the hoist and it was that small i wold not
make the customer pay for accentric bolts
i would just loosen the craddle bolts
and adjust the camber and caster in the raised postion with live readings and redo a caster sweep small toe adjust and vola 35 mins 65 bucks done . providing the springs are not broken or well sagged out and front end parts not worn out