F37 TCM tranny changes?

Jett · **Joined:** Fri Apr 17, 2020 12:07 am **Posts:** 250

How do I tell if my TCM is Chrysler molested with f37? I thought it read somewhere that you can tell by where it shifts into top gear or where it downshifts from it? Mine seems to be kicking out of top gear once you slow to below 55mph, where my other one seems a little higher like 59/60.
Anyone know the tells?

flash7210 · **Posted:** Fri May 29, 2020 7:44 pm

There should be a sticker under the hood indicating that the ECM or TCM has been updated.

Jett · **Joined:** Fri Apr 17, 2020 12:07 am **Posts:** 250

This is an eBay tcm, mysterybox

WWDiesel · **Posted:** Sun Jun 21, 2020 1:58 pm

Jett wrote:

How do I tell if my TCM is Chrysler molested with f37? I thought it read somewhere that you can tell by where it shifts into top gear or where it downshifts from it? Mine seems to be kicking out of top gear once you slow to below 55mph, where my other one seems a little higher like 59/60.
Anyone know the tells?

From an older post:

Quote:

1. a pre-F37 TCM will engage TC final lockup @ ~58 mph on flat level road during light acceleration and will remain in TC lockup down to ~50mph
2. a post- F37 TCM will engage TC final lockup @ ~62 mph on flat level road during light acceleration and will remain in TC lockup down to ~55mph.
*transmission Oil temperature >40° F

Without prior knowledge of the vehicle a TCM was removed from, or information supplied by its owner, buying a used TCM would be a total crap shoot when it comes to wanting a Pre-F37 or GDE tuned TCM.
GDE may can provide information on a TCM they have reflashed if you know the vehicle it was removed from and the owners name and if they are willing to do so??? :juggle:

Not sure after all this EPA crap. :banghead:

F37 TCM tranny changes?

Who is online