285s: Stock Wheels + Spacers to new 17x9

It’s time for new tires and I’d like to get rid of my current set up that includes wheel spacers. Help me do math stuff

I currently have stock wheels with 1.25” spacers, 285/75/16 Hankook Dynapro ATMs (discontinued).

Stock wheel: 16x7 +30 offset
1.25” spacer = 31.75mm
Resulting in -1.75 mm offset (?)

Switching to a 285/70/17, probably KO2’s. The wheels I’ve got my eyes on are 17x9 with -12 offset.

The change in offset should push things out roughly 0.4” further than my current set up, but since I’m going from a 7” wheel to a 9”, the tire will stick out 2.4” (0.4” + 2”) further than my current set up?

Is that right?

 

For reference, here's my old truck with 17x8.5 -10 wheels with 305/65/17 tires which are a little wider tire than the 285. So with the 17x9 -12 wheel you would be looking at around a 1/4" more sticking out but might not look like it with the narrower tire.

 

Nice. Thanks for the pic

 

It'll stick out about 1.4" further (0.4 + 1). Going from a 7" to a 9" wheel will increase 1" in both directions (inward & outward).

 

Stock or aftermarket UCAs?

 

Thanks. I plan on taking some before and after measurements and report back. I’d imagine if the tire should fit a lot better onto a 9” wheel over the 7”

 

The truck had SPC adjustable upper control arms which I thought worked great for easy adjustment.

 

Good deal, that’s my current set up.