New ECM!?

[Jfireboy1]

Hey guys! Don't know if this will do any good or help resolve any issues but I'm considering putting in a brandnew ECM to make sure that the one currently in my truck is not causing all the problems I've been getting with my tranny! Does anyone know what exactly can be controlled through them on the tranny? Any input is greatly appreciated as that I don't wanna rebuild my tranny and have something go wrong for the third time!

 

[WOT]

For the non-diesels, the EMC controlls:

Governor Pressure
Torque Converter Clutch
4th Gear shift solenoid

Thats it.

Now, it takes input from the Output Speed Sensor (OSS), the Governor Pressure Sensor, and the Trans Temp Sensor (last two are the combined in the same sensor part).

But those just basically affect the shift/lock schedule.

Line pressure, Throttle Pressure (detent), and all the other parameters are mechanical, and the ECM can't do anything about them.

So, except for shifting at the wrong time, the EMC can't harm the tranny. Shift firmness, shift speed, and all clutch timing parameters are not controlled by the ECM.

 

[SANTEEN]

Joe,
I think once u get ur transmission rebuilt, you'll be fine. JUST KEEP THE BANDS ADJUSTED!!!!!!!

 

[JTS VENOM PERFORMANCE]

I think you should just sell it or trade it for a bone stock srt10, and leave it be.

 

[rottenronnie]

An improper tune can cause your automatic to have brutally hard shifts.

 

[WOT]

An improper tune can cause your automatic to have brutally hard shifts.

Only because it might shift late. Shift quality is not controlled by the ECM. The TV cable controlls shift firmness more than anything. The EMC has zero input into shift firmness. Now on a diesel, the EMC can control the shift firmness because the TV cable is replaced with an electronic module that basically does the same thing (pulls on the TV valve). On those, it is critical that the EMC tranny parameters are set up properly, just like we have to have our TV cable adjusted properly.

 

[rottenronnie]

Only because it might shift late. Shift quality is not controlled by the ECM. The TV cable controlls shift firmness more than anything. The EMC has zero input into shift firmness. Now on a diesel, the EMC can control the shift firmness because the TV cable is replaced with an electronic module that basically does the same thing (pulls on the TV valve). On those, it is critical that the EMC tranny parameters are set up properly, just like we have to have our TV cable adjusted properly.

If you muck around with tunes (through the SCT software) and not even touch the TV cable, you can make the trucks shift hard enough to break things...Ask me how I know...

 

[WOT]

What did you change in the ECM that would break your tranny?

 

[rottenronnie]

What did you change in the ECM that would break your tranny?

I was "experimenting" with timing and fuel tables using the SCT Advantage software and, believe it or not, NO changes were made to the automatic. But, nevertheless, my changes did impact how hard it shifted. In fact, it shifted so bloody hard under W.O.T. that with DRs, it broke an Input shaft. I am talking Neutral-Drop hard ! It was Fun while it lasted (more mid-range power) but the tranny didn't think so..

Chris Jensen just recently sent me a tune that shifts harder than my last one from him (by request)..

As for specifics, you would have to talk to a Tuner that is more knowledgeable about it than I am.

Ronnie