I upgraded my tires to 285/70/17's, about 20,000 miles ago. Another forum member asked me if I adjusted anything such as the t-bars, which I did not. I noticed that the stock tires on the 20" wheel option had about the same diameter as my new ones (33"), parking next to a guy with a Hemi Sport.

My question is, is there a difference in components or adjustments between the suspensions of trucks that came stock with 17" rims versus the ones that came with the 20" wheel option?

 

From what I understand there is no difference. The only thing I could think would be different is 3.92 vs 3.55 gears. But then again my truck has 3.92 and 245/70/17's on it.

 

Even the gearing in the rear is optional.
You can get 20"s that have the lower ratio... Wheel OD is almost identical. (I'm pretty sure it's within 3/16" difference)
It you ever had a shadow of thought about towing, you DO NOT want the 3.55 gears.... bad juju.
3.92 minimum, or higher.

With an 04, you have torsion bars.
I'd suggest looking into the "Tighten the T-bar and get an alignment" levelling method, mainly for looks, but if your only concern is towing, don't worry about it...
My 03 QC 4.7 with the 3.92 towed my boat (700lb tongue weight, 9800lb gross) and I honestly didn't feel it back there... The only reminder was the sound of the hitch in the receiver under accel/decelleration. Never felt it in the pedal... but actually the ride felt smoother.

 

I have neither and have no stake in this, but a tire site that I was on indicated the tires that most commonly found with 17" wheels (265/70s) are 1.5" larger in diameter to the 275/60s found on the 20" wheels. Now your making me go back and check.

 

Actually, the stock tires on the 17"s are 31.6" in diameter and the stock 20" Goodyear (read as CRAPyear) are true 33"s.