Jeep Tire Size - Fixing the issue or Not?

[mikel]

update is in the works.

[amw]

The 9t08a_export.crom that I am currently using has a working tire recallibration function and I was thinking about updating my tool with the latest crom file...was told that I wouldn't lose any functionality. However, according to this thread, the latest crom file is problematic.

What's the deal guys? I'm glad I have not yet made the change! Why am I being told one thing and everyone else is being told..."it's in the works"?

[mikel]

It is calid based, so if it works for you now, you should be fine after updating.

[amw]

O.K. Gotcha...I'll attempt to load the latest crom then.

Thanks for the clarification!

[Flying2Fire]

John,
Any luck with this subject matter?

[mikel]

Last update we tested all Wrangler were working fine.

[Flying2Fire]

Mike, I loaded up 9R11 last night with the the setting at 33" (I run MT 305/70R16 MTZ actual 33.1"), during the test drive there no change to the speed-o, (same as previous 9R10 at 33"). The speed starts of ok until 40MPH at 50 its off by 5MPH and 8+MPH at 70. So I tried 35" setting The numbers where the same. Any thoughts

2006 Rubicon LJ Wrangler, 4.0L, 6 spd, NV241, 4:11 - U7137

[mikel]

can you post your calibration ID please?

[mikel]

Actually, try 9t12 please.

[Flying2Fire]

Mike,

Thanks for the assistance, at least I am now closer than ever before, and tire size changing work. I'll try the mileage boster when I drive up to Daytona for Jeep Beach, and let you know what the change is.
Attached is the files, just incase someone gets froggy and adds 305/70R16 to the list.

Thanks again

[WKgrand08]

Quick question. Has anyone with a 08+ Grand Cherokee tried adjusting tire size manually in an exported tune and then re-loading the tune to get the tire size corrected? Just wondering since we know the quick adjust before or after doesn't work. I want my speedo fixed for my larger tires dangit!

[Flying2Fire]

Mike,
Made the runs to and from Daytona, Gas milage was improved by about 2 MPH using 93 Oct fuel (hotter afternoon) and no change for 87 Oct fuel (early morning cool).
A couple of things I did note the Jeep is way down on power and requires shifting to lower gears to go over passes and causeways.
The Idle is at the seems to be at the correct RPM, but does feel rough.
Any thoughts?

[mikel]

Its going to be way down on power if you're running 87 octane on the 93 tune...thats not an option.
You need to run 93 with that tune or go down to the 87 tune.

[j33p]

Quick question. Has anyone with a 08+ Grand Cherokee tried adjusting tire size manually in an exported tune and then re-loading the tune to get the tire size corrected? Just wondering since we know the quick adjust before or after doesn't work. I want my speedo fixed for my larger tires dangit!

mee too...

[Gallo]

What are the addition to 9t12 over 9t11. Anything on Tpms turn off and light. And sway bar turn off on rubicon models?