Going to 20" wheels from 18"

tpdolph · April 22, 2012

was wondering if I needed to have my speed-o corrected when changing to the 20" wheels, seems likely I would, can the dealer do this?

SouthCo · April 22, 2012

The size of the wheel doesn't matter. The overall diameter of the tire does in regards to the speedo. What size tire are you planning on running? My truck didn't come with 20"s but I put oem 20"s with the oem size of 275/50/20 which has virtually the same outside tire diameter of the stock setup.

So my speedo wasn't affected.

tpdolph · April 22, 2012

Thanks SouthCo, Actually the wheels you have are the ones i'm wanting to purchase (nice set-up you have) My current wheels are P265/65R18 and the ones I'm wanting are your size P275/55R20, So i should be good to go? Also Did you get the TPMS installed before or after you purchased your wheels, the reason i'm asking is, don't they have to take the tire off to install them? Thanks

SouthCo · April 24, 2012

All tire manufactures actual sizes can vary somewhat. So a goodyear p265/65/18 tire may have a larger or smaller diameter than a bridgestone p265/65/18 tire. With that being said, you should be fine. The difference in diameter should be less than an inch.

I got my 20" wheels/tires off ebay and the were new takeoffs. They already had the TPMS in them and were ready to bolt on to the truck. So I just had to program them to the truck. If you add the tpms after the fact, yes the have to break the bead on at least one side to get the TPMS installed.