Alignment problem

[OneBadasz71tahoe]

I just got this truck about a month ago and have had this problem since purchase. I have a 1998 2 door Chevrolet Tahoe z71 4x4 with about 90k on it. It is completely stock. The issue that I am having with my truck is when I let go of the wheel on level ground at low or high speed the car will drift to the right. I end up going down a normal straight road with my wheel cocked between 10 and 11 o'clock. My tires have been balanced, and my front end has been inspected and aligned to GM specs by my local Chevrolet dealer. I even took it back to get them to recheck their alignment because it was continuing to drift to the right and they claimed it was the tires. I have BF goodrich All-terrains K/O 265/75/R16. Before I go out and replace my tires do you have any ideas. My friend said that his 1997 Silverado did the exact same thing and it ended up being something really simple in the steering or front end that they discovered after a bunch of wasted time inspecting ball joints and and tire rods. The only problem he couldn't remember what it was or where he had the work done. I have jacked the front end up and there is a slight bit of play in the wheels if you try to move one of the front tires from lift to right. Does this sound normal or do you think I need to replace my steering box or pitman arm and idler arm? I appreciate your help.

[GMMerlin]

A slight drift to the right is normal (alignment specs are written this way....if you let go of the wheel, your vehicle will go right instead of left into oncoming traffic)
You also have to take in account road crown..you will not find a flat road, all roads are graded and paved with a grade from center..this is for drainage and can aggrevate the drift to the right or left.
First thing you can do is swap your tires side to side..if your drift straightens out or drifts to the left, its your tires.
Also any componant that is loose on the front end may cause this also

[maxwedge]

GMMerlin, about the built in drift, every alignment spec I've seen and used does not show a difference in left/right camber or caster that would account for an intentional drift, some vehicles have slightly more or less camber on the lt to compensate for driver weight, but this may be .2 degrees at most, the resulting cross camber would not cause a pull, maybe something in the suspension design I am missing? Setback usually displays .1 degree, again that would not cause a pull, usually just calibration of the equipment or manufacturing tolerances.

[GMMerlin]

Originally Posted by maxwedge

GMMerlin, about the built in drift, every alignment spec I've seen and used does not show a difference in left/right camber or caster that would account for an intentional drift, some vehicles have slightly more or less camber on the lt to compensate for driver weight, but this may be .2 degrees at most, the resulting cross camber would not cause a pull, maybe something in the suspension design I am missing? Setback usually displays .1 degree, again that would not cause a pull, usually just calibration of the equipment or manufacturing tolerances.

The alignment spec is written not to take in account the road crown.
Since there is no compensation for the crown, the vehicle will drift away from the crown.
Also most caster/camber measurements are taken from the ground.
If the measurement were taken off the frame (suspension geometry) there is a difference.
There were some spec changes on C/K trucks because the spec was off the frame and not from the ground..This caused some confusion during alignment adjustments.

[maxwedge]

Wow, who made that mistake in the specs, what years?

[LongIslander26]

Originally Posted by GMMerlin

The alignment spec is written not to take in account the road crown.
Since there is no compensation for the crown, the vehicle will drift away from the crown.
Also most caster/camber measurements are taken from the ground.
If the measurement were taken off the frame (suspension geometry) there is a difference.
There were some spec changes on C/K trucks because the spec was off the frame and not from the ground..This caused some confusion during alignment adjustments.

I usually set the right side camber a little higher than the left for just these reasons. Usually anywhere form .3 - .5 degrees is good.

[maxwedge]

Where on Long Island, from No. Bellmore here. So you say you are arbitrarily setting the camber specs out of range? I know of no oe mfg that suggests or publishes doing that, help me here.

[LongIslander26]

Originally Posted by maxwedge

Where on Long Island, from No. Bellmore here. So you say you are arbitrarily setting the camber specs out of range? I know of no oe mfg that suggests or publishes doing that, help me here.

(From St James, but I live in AZ now.)

As to the alignment specs, they're not "Arbitrary". Normally, if you look at the published specs, it's shows the caster specs at "3.5, +/- .5" So, I'll set the left side to like 3.3 or 3.5, and the right to like 3.8 or 4.0, and still be within specs, then set the camber and toe to the nominal specs, equal on both sides, and then the caster negates the road crown, and the equal specs on either side reduces any tire wear and pull/drift issues, and you're good to go.

[maxwedge]

Ok cool, so you are not building in a drift setting. As we know camber has the single greatest effect on steering pull so I see what you have done, you stated camber in your post but this explanation clears things up.

[LongIslander26]

Originally Posted by maxwedge

Ok cool, so you are not building in a drift setting. As we know camber has the single greatest effect on steering pull so I see what you have done, you stated camber in your post but this explanation clears things up.

You are correct, I did say "Camber", but I meant "Caster". My Bad.

[sa200]

You better switch your front tires side to side to see if one of the tires is pulling. Also check to see if your truck has been in an accident before (bent frame ect.)