1998 concourse drifts to the left

[Blue~Go]

I also thought that alignment should be done with a typical load (especially with something like an RV which can vary quite a bit vs. a car). Is that no longer true?

[Scott]

It's true. Or definitely advised. A heavy load in rear affectively changes caster (assuming that load changes rear ride height). Varying front end load changes camber (with our suspension design). and even with the robust mechanicals that we have, things still flex and move around, including the frame, the body, and most suspension components. That's more significant in a dynamic situation but even in a static state on a rack, load matters. But nothing matters more than a competent technician.

[dougm]

Do you guys seriously think that vehicle manufacturers do not take into account the gross vehicle weight loaded and unloaded as well as the intended purpose of the vehicle when it is built and those specs placed in print for their technicians to follow? Im not saying you cant load your truck down, what im saying is that it is not required and your wasting your time, unless of course you have worn out suspension thats going to cause excessive spring sag in the rear or youre overloading the vehicle to begin with. The ride height is what affects the caster not the load, needless to say if your springs are worn out or your overloading the truck beyond manufacturers specifications your going to have issues.

[Scott]

"Do you guys seriously think that vehicle manufacturers do not take into account the gross vehicle weight loaded and unloaded"

They take mass into account, of course. If there are posts suggesting otherwise, I missed them.

"as well as the intended purpose of the vehicle when it is built"

They do consider "intended purpose" when they design a vehicle, yes.

"and those specs placed in print for their technicians to follow?"

Shop manual?

"Im not saying you cant load your truck down, what im saying is that it is not required and your wasting your time, unless of course you have worn out suspension thats going to cause excessive spring sag in the rear or youre overloading the vehicle to begin with."

"Loaded down" (max) and "typical load" are not necessarily the same. It's not required, but if one is looking for the most precise alignment possible, it makes sense to have the vehicle weight close to where it would be during typical operation. I'm not sure where the "waste of time" comes in.

"The ride height is what affects the caster not the load, "

Ride height affects caster. That's correct. But load can affect ride height (stated previously, maybe ambiguously).

"needless to say if your springs are worn out or your overloading the truck beyond manufacturers specifications your going to have issues"

You're right again.