Need help understanding offset and backspacing

[tinner]

First let me thank everyone here for a wealth of knowledge I have gained of the last several months studying this forum. I have a 2012 QC 4x4 5.7 that is about to receive Bilstein 5100s set to 2.1 up front with 1" spacers and Bilstein 5100s in the rear as well as airbags.

Now for my questions. I also want to change my wheel/tire setup from the stock 20" setup that it came with and go to 17" wheels with 285/70 R 17 tires, most likely one of the more aggressive A/T tires (haven't decided exactly which tire yet)

I have searched and read as many threads as I can find regarding this setup and am totally confused regarding backspacing and offset when changing or ordering wheels. Can someone please tell me what backspacing or offset or combination thereof I need for this setup???

Thanks in advance!

 

[RamWrayzor]

With that set up 0, or -6 offset will work great since the tires won't be bigger than stock. Backspacing and offset are the same, just depends on which figure you wish to use. With trucks, a negative offset brings the wheels out from the truck for a more aggressive stance.

 

[tinner]

Thank you very much for the reply! That is what I was trying to figure out is what would give a bit more aggressive stance or more stand off from stock.

 

[012RAMbo]

And to add a little bit so you can fine tune if you want. Your stock 20s are 9'' wide with +19mm offset. 1'' is 25.4mm, so if sticking with a 9'' wide wheel, every 6mm of offset will move your wheels in or out 1/4''. So if you go down to +12mm, thats a 1/4'' sticking out further that your stock wheels. Like said above going toward 0mm offset or negative is pushing the wheels away from the truck and going higher in positive offset brings them closer to the truck.

 

[BOWERSFJ]

I went with a 9" wheel with 0 offset. It's perfect for my 12.50's. It might look a little odd to push those 285's out any further with a -6 or -12 wheel. I wouldn't go any less than 0 offset. You might want to check out the Toyo ATII's. They have a 285/75R17 that would be a nice upgrade from the stock size, without gettin crazy. Wait, just did some searchin . . . Nitto Terra G2 has a new size . . . 295/70R17 . . . The G2's a getting really good reviews. Throw that on a 0 offset wheel with the lift amount you are puttin on, and you'll have no rubbin, and it would look great I think. You're in New Mexico for gosh sakes . . . No sense settling for a skinny little 285 . . . Lol . . . Good Luck