Wheel Size Swap Question

[Beamie]

If I swap wheels and tires from 18" to 20" is there something in the electronics to be changed? Our '08 wheels are badly oxidized and get slow leaks in cold weather (corrosion on bed surfaces assumed), but it is ending up hard to find 18" take-off wheels now. There seem to be a better supply of 20" wheels so what would I be getting into with regard to setting up the truck?

Edited September 6, 2020 by Beamie

[CamGTP]

You only have to change stuff in the computer if you are super paranoid about it being 100% accurate.

 

If you keep the overall tire size pretty close to the same you will not really notice much difference at all. There are online calculator you can plug the data into to see how far off your speedo will be. Depending on what you do it may be off by 2-3mph at 70 going down the freeway.

[Beamie]

2 hours ago, CamGTP said:

You only have to change stuff in the computer if you are super paranoid about it being 100% accurate.

 

If you keep the overall tire size pretty close to the same you will not really notice much difference at all. There are online calculator you can plug the data into to see how far off your speedo will be. Depending on what you do it may be off by 2-3mph at 70 going down the freeway.

So nothing involving ABS or anything but speed accuracy?

[CamGTP]

Correct, the ABS will still function the same way.

 

People will put 33's or 35's on their vehicles all the time without doing a thing, they just choose to live with very far off speedo.

 

So going from say a 265/65/18 to a 275/55/20 is a change in size and will put the speedo about 1mph different at freeway speeds. The larger the tire you go, the more off it will be obviously.

Edited September 7, 2020 by CamGTP

[ClipperSkipper]

The short answer is no, you don't need to change a thing. Case in point, I changed from a 16 inch, to an 18 rim/tire combination on my 2001 Sierra. The tire diameter change was 1/10 of an inch.