[01Cummins24v]

I have a 95 cummins with a 47rh in it. The truck shift into OD at 46mph. It too early for me when I am towing or just cruising. Is there anyway to adjust the shift into OD> I would prefer it anywhere from 50-55mph. I know I can delay the shift with the OD off buttom but I dont want to have to drive it like that. I have read about adjusting the TPS but I am not sure it will make the difference I am looking for.

I have searched, cannot find anything for my specific question.

 

[1workinman]

95 pcm

I believe that there was a reflash that could be done to the pcm that does that and I would also like to do that to my truck as I have a 95 . I don't know of anyone that has the tools to do that . jim

 

[zfaylor]

I am not positive on the OD shift but the regular shifts are controlled by a mechanical governor in the tail housing on the rh transmissions. The re transmissions control shifts based on the pressure transducer and governor solenoid.

 

[country_hick]

You can change shift points. It requires adding a pentiometer to the TPS. The link below shows the wiring needed. I suggest you read the entire thread.


Dodge Diesel - Diesel Truck Resource Forums - View Single Post - Installing a Potentiometer in place of the TPS

 

[RamCumminsRob]

What Effect?

You can change shift points. It requires adding a pentiometer to the TPS. The link below shows the wiring needed. I suggest you read the entire thread.


Dodge Diesel - Diesel Truck Resource Forums - View Single Post - Installing a Potentiometer in place of the TPS

Hick,
What does this end up doing?
A later shift into 4th gear?

 

[country_hick]

Basically, it changes the electrical input the TPS sends to the computer. That changed voltage either makes the shifts (all of them) occur sooner or later depending on how it is set. Illflem (on here) is who posted that over there.

 

[zfaylor]

That will only affect the OD shift. An rh is completely mechanical with its 1-2-3 shifts via the governor in the tail housing. Hints no pressure transducer or governor solenoids in the valve body or limp mode (2/3 starts) like with the re.

 

[country_hick]

I missed the part where it was a 47RH.

 

[RamCumminsRob]

Me Too

I missed the part where it was a 47RH.

I missed that too.
Good to know.
So much to learn about these trucks.

 

[thoroughbred]

country_hick is right, the way to do it is with the potentiometer. Its not too bad to do.

My guess is your actually shifting into 4th sooner, but what you are feeling at 46-47mph is the TC locking up.