Eeepj

Installed 33" tires and the speedo and shift points on the tranny seem off. Does anyone know if the Pro-cal module will fix the shift points? It says it will adjust the speedo.

nthinuf

Re-calibrating will get you back to your stock shift points, but you can not manually adjust them.

The Flashpaq has this feature, but you have to pay extra to download it I believe.

sm_rubi

Spot on about the ProCal...and Superchips has the shift points option at an additional cost for the download. I think the tow tune uses different shift points which gives better performance but uses more gas.

Eeepj

Perfect. Thanks for the info. I just want to get back to the stock shift points cuz it downshifts alot at highway speeds.

Hulk

if im not mistake some guys with autos will use the procal to tell the computer that you have a larger gear that what is actually in your axle which in return with help with your shifting ;] it will shift like it has a 4.10 if you tell it you have a 4.10.. make sense? lol

Eeepj

Can that damage the transmission?

Hulk

not that i know of.. it just programs the computer for a different gear ratio which will change the shift points accordingly. its basically a way to trick it into shifting as if you had a 4.10 gear ratio if you have the smaller gears. ;D if you search over at wrangler forum there a few guys that have ran like that for a long while

nthinuf

It is my understanding that the JK gets all of it's speedo/odo data from the sensors at the wheels, and a gear change does pretty much nothing. (that function is used on other vehicles, just not the JK).

Even if it does work, it would be the same as plugging a different tire size in, which may change the shift points, but will also cause the speedo/odo/mpg's to be off again.