Buying Used Gears Question

So I decided I wanted to put 4.88's in my truck, figured I'd spend the money buying something I'll feel/notice everyday driving.

Conveniently I have a buddy who has nitro 4.88's and an auburn who is going to 5.29's and offered me a sweet deal on his 4.88's/auburn that I couldn't pass up, with this said I also have a great installer as well who is familiar with gears that I trust.

Any issues with used gears as long as installed correctly?

 

Buying from a known source such as this you’d have my blessing.

Maybe see if your friend will let you have his whole diff. You just bolt it into your truck. No set up nothin.

He has to set up his 5.29’s anyway. So why not set em up on your diff??

 

He is driving out of state to have the swap done. He offered to have me drive as well and just swap housings but the auburn needs a rebuild anyway and i’d like my guy here to do the install even if it’s a little more work than just swapping a housing