Larger wheels on Jeep - what needs to be adjusted?

[Crossfit Jeep]

Happy Sunday! Now if I add larger wheels to my Jeep, other than speedometer and traction control (I think I need to adjust??) is there anything else that would need to be adjusted?

Thank you for your help!

 

[smritte]

Larger tires, nothing other than speedo and that's only if it can be adjusted. Most require a modification to calibrate. Most of the time unless you go real big, you don't need to recalibrate. You just need to be aware of how far off your speedo is. With 35's on my cruiser, i'm reading 4mph slower. My Tacoma with 32's is almost two mph slow. Check with a GPS.
Depending on what you do, how big of tires and how you drive will determine what needs to be modified.

 

[Crossfit Jeep]

Is a GPS that accurate even with a spread of 1-2MPH?

 

[smritte]

Most are good to .1 mph. At least all the ones I have ever seen or used. Some of the high end custom gauge sets use GPS instead of transmission for speed data. I believe (its been a while) the manufactures accuracy needs to be within 5%.
One of my jobs in the shop was speedo calibration. I had to use mile markers before GPS came out.

This will give you an idea where you stand. You should also know how wide your rims are.
Tire size calculator

The manufactures predicted size is based on a certain width rim. If you go wider or narrower, that will effect the diameter some which will effect the speedo error some. If you doing custom rims, be aware of the stock vs new off set. This chart will tell you the width difference so you can buy the correct off set if you go to a much wider tire.