The rear suspension is not adjustable. So, if in a bad accident if the rear suspension is bent, you'd bend it back, or replace the bent parts. But it's not adjustable in the sense the front is adjustable.
Front end is a 2 wheel alignment, with the rear not adjustable
Front and rear is a 4 wheel alignment, front and rear adjustable
Front with reference to the rear is a thrust angle alignment, front adjustable, but a rear-wheel drive vehicle
So, there sort of is a four wheel alignment for trucks. It's a thrust angle alignment that aligns the adjustable front relative to the non-adjustable rear, because the rear is the drive axle. It's more than a front wheel (2 wheel) alignment, but isn't quite a four wheel alignment. It's a two wheel with reference to the rear drive wheels.
Ace! You kinda lost me. Sorry for my lack of technical understanding.
For the front - (independent suspension). I understand there is (1) tow, (2) camber and (3) caster to adjust.
For the rear - (fixed axle). Are you saying that the rear tires/axle "CAN" be align/adjust to coincides/parallel with the front tires?
Can you or anyone link me a website with photos so I can visualized what/where is being adjusted on the rear axle.
No, and I'm sorry I brought it up. The rear aren't adjustable; however, there is an alignment relative to trucks that's not a two-wheel alignment.
On a rear wheel drive, like a truck (where the rear isn't adjustable) there is a thrust angle measurement (where the drive wheels point...which doesn't have to be EXACTLY straight, but should be darned close). What happens then is the front, which is adjustable, is made to point the direction the rear points (which may or may not be EXACTLY straight). So, really, on a truck like yours or mine they take a measurement of where your rear tires are pointing even though they aren't adjustable (or because they aren't adjustable, and because it's a rear wheel drive) and they then adjust the fronts to point the same direction/angle. Then, based on that they adjust for camber, caster, toe.
So, they aren't adjusting the rears to coincide with the front, they are adjusting the front to coincide with the rear (since you can't adjust them), then they are doing the normal two-wheel alignment stuff. It's a thrust angle alignment, or it's also known as a two-wheel alignment with rear wheel reference, or something similar to that. Sometimes places call it a four wheel, but it's not a four wheel...it's just a front wheel with rear reference, thrust angle, etc.