Jeep Garage  - Jeep Forum

Jeep Garage - Jeep Forum (http://www.jeepgarage.org/forums.php)
-   Suspension/Driveline/Brakes/Wheels/Tires (http://www.jeepgarage.org/f109/)
-   -   Another tire size question (http://www.jeepgarage.org/f109/another-tire-size-question-22541.html)

illudezion 04-29-2011 05:24 PM

Another tire size question
 
I'm looking into 20's with larger then stock tires. Do you and can you get our cars reprogrammed to compensate for the larger diameter?

JayB 04-29-2011 05:59 PM

Re: Another tire size question
 
Seems like you need an after market programmer.
When I went in to the dealer to get the ESC TSB the dealer said he couldn't do it.

I was just going to wait to do mine until the Superchips came out.

illudezion 04-29-2011 06:25 PM

Re: Another tire size question
 
That sucks. The size i'm planning on going is almost 5 mph a 7.29% difference

mhassler 05-02-2011 08:04 AM

Re: Another tire size question
 
illudezion,
You certainly can and perhaps at your dealership. My local dealership will re-calibrate for me when I install my lift & 33s.

Remember a tire size increase doesn't change your mph linearly, it is percentage based. Here is a good explanation http://auto.howstuffworks.com/car-dr...eedometer4.htm and here is a good tool http://www.csgnetwork.com/speedocalibcalc.html.

And this works both ways, increase or decrease in overall tire O.D, not necessarily rim.

illudezion 05-02-2011 01:23 PM

Re: Another tire size question
 
Thanks. I knew that. I want to go with larger series tires on the 20s so the OD is larger and will be a 7.29% difference. Hopefully my dealership can do it.

JayB 05-02-2011 01:31 PM

Re: Another tire size question
 
What size tires are you going with?

I was under the impression 32" tires were pretty much the biggest you could go on stock suspension. That being said.... those tires are about 5.3% larger. Where are you getting 7.3%?

illudezion 05-02-2011 06:21 PM

Re: Another tire size question
 
I was actually thinking of going 22s with 275/50/22. Which would have a OD of 32.82in. I just think that 40 series are too skinny looking for the car.

mhassler 05-02-2011 07:07 PM

Re: Another tire size question
 
^^Hate to say it but a 32.8" tire won't fit without a permanent lift. If you want a 22" rim with a 275 section width (10.8") you will need a 275/40r22 (30.6") or 275/45r22 (31.7") tire.

Don't forget that if you get to wide you're going to need spacers, if the rim offset us the same as OEM that is.

illudezion 05-02-2011 10:31 PM

Re: Another tire size question
 
Thanks for the input been working on cars for a long time and know all about offset and OD. My original question is can the Jeep be recalibrated.


All times are GMT -5. The time now is 09:21 AM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community