Spacing wheels out another inch as stated above modifies original steering geometry, center point steering modification puts larger load on wheel bearings, wears tires more.
Ed
You could buy stock GM wheels with a wider offset so that's not accurate. It doesn't change the center point because it's still at 90 to the center point, Weight of the truck isn't changed so larger load on the bearings is not accurate either. Look at a 3/4 ton a 1 ton and then a 1.5 ton and tell me one will do any of the thing you've stated. each has a different off set wheel and track width due to wheels and all share the same axle and the same center point.
It doesn't change ackerman either. even though they are outward 1" they are still well within the wheel wells
