Engine/Transmission (1998.5 - 2002) Auto transmission downshifting ??'s

[SAronson]

While driving around town, my transmission stays in 3rd gear until I come to a stop. It down shifts to 1st fine, and runs up through 2nd and into 3rd (and O. D. , if I don't turn it off). The problem is that I would like it to downshift into 2nd at slower speeds (i. e. 5-15 mph) without having to "stab" the accelerator. Being in 3rd at these slow speeds is IMO hard on the transmission, and it lugs the motor. If I have to "stab" the pedal, it downshifts but it accelerates hard... which is fine if I want to race around, but I'm trying to get good mileage and not lug the motor. I have played with the T. V. cable settings, and if set too tight, the truck wants to pull through the brakes while at a stop... . also hard on the transmission (heat).

My questions are:



(1) Is this normal for the auto transmission?

(2) If not, is this electronically controlled in the PCM (or in the APPS), or internally in the transmission?

(3) How can I get it to downshift the way I want?



I did "search", but found nothing. Thanks for any and all input!

 

[SAronson]

I just updated my truck profile after starting this thread. I hope it shows up.

 

[AClayton]

I've spent $3K worth of ATS upgrades on my transmission and mine still does that. It has been serviced and adjusted by myself and then by qualified mechanics to get this issue resolved. I have been told that this is how it works and to get used to it. My trans tested fine and when I did my performance upgrades,I called ATS and they suggested the TC and VB to help with the added power. So I still have a stock trans with HD upgrades and to date,do not have problems with reliabilty. I do however,question the way the transmission shifts and lugs the motor. A TC lock-up controller has been one of the best upgrades on my transmission and I just manually shift it when needed. I will be checking this thread also for ideas!

 

[Vaughn MacKenzie]

It's the way the Dodge-o-matic works. My '98 does the same thing. If I slow to 6-8mph and gently step on it it stays in 3rd. If I slow to about 3-4mph it'll start off in 2nd. . . maybe. If I slow to about 2mph then it goes to 1st (usually). I had a transmission shop check it out and after a test drive they said it's normal and working EXACTLY as designed

 

[AClayton]

Thanks Vaughn,I had a feeling there was nothing to do about it. If a transmission manufacturerer were to design a computer to intercept our factory program and make it shift like an Allison,I would buy it without hesitation!!Hint!Hint!Good thing it's a Cummins behind this trans and not a Powerstroke,because the computer really lugs the engine. It seems when you need the most power going uphill or something,the trans will upshift and kill the motor... . dumb. Just add trans woes to the Dodge list of gremlins including fuel system and weak front-end awa the cheap dash in these trucks.

I still love my truck though because I think a 2nd Gen truck just plain looks good and runs great... . after you take care of the problems that DC left us!!

 

[SAronson]

Wow! I don't know if I feel better or worse after reading this is "normal" shifting for the "dodge-o-matic". No wonder the manual trannied trucks get better mileage.



So, how is this downshifting controlled? I'm assuming it's in the programming of the PCM. If so, how can we re-program the PCM? I think this problem might also be enhanced by the addition of my RV275's and EZ fueling box, which require much less pedal (APPS) signal going to the PCM. It would be nice to have a product to adjust this program like the Smarty does for the ECM.

 

[BILLVO]

Mine has the opposite problem. When coming from higher speeds in OD it will down shift its self pretty noticably to 3rd then 2nd. It feels like I hit the OD off button then manually pulled it to 2nd when coming to a stop, It will actually rev the engine up when it down shifts. It only does it when coming from higher speeds for a distance though. I had a thread about it a couple weeks ago and nobody answered that one for me.



It started doing this after snapping my output shaft. I changed out the speed sensor and it didn't help it.

 

[Vaughn MacKenzie]

I don't know automatics but I believe the shifting RPM is dictated hydraulically and not a lot can be done to change it. Someone correct me if I'm wrong. The only thing electronically controlled is lockup.

Vaughn

 

[AClayton]

SAronson,

I too noticed that my transmission shifts better when I turn down the Smarty... . I leave mine on SW4. In my truck,the lower SW levels allow more throttle input vs. pushing accelerator down 1/4 inch and getting 450hp instantly. When I did the upgrades last year,it shifted 'firmly'when Smarty was at the lower levels. It shifts without slipping now but a little mushy compared to when 1st installed. That's when I decided to have ckd out and told it was fine. When it craps out ,I will get the performance transmission rebuild. But for now,it is working and the fluid is red and my temp never exceeds 150*.