Im shopping the complete upper arm and there are several differences. One being the slightly longer to correct camber on lifted trucks (Rouge Racing, Rough Country) and thats clear to me but..
Why do I find arms that state for replacing cast aluminum army only (replacement parts are always cast iron) and will not replace factory iron arms. I also find arms that state the other way being they only work with iron factory arms and not aluminum.
Clearly buying the wrong part would be could be bad but I cant wrap my head around when shopping for a upper arm 2wd 2015 Yukon XL, I find both type listings and both claim fitment. Mine is cast aluminum but did GM really use two different arms in the same year on same 2wd truck and in what way would it matter?
I also come across uppers listed only for police package and wont work with any other. Really? Id think if I was lowering then it would be perfect (but Im not. Actually going up a few inches)