Chrysler Repair: Shifting problem: 90 Ram


Question
I have a 90 Dodge Ram 4x4 with a 318. I converted it from TBI to a carburetor system. It shifts into 2nd gear at about 25 M.P.H. and shifts into 3rd gear at about 48 M.P.H.
 Is there a way to get it to shift sooner, especially 3rd gear. It would be nice to get into 3rd gear at about 25 or 30 M.P.H.

Answer
Hi Lindell,
Which transmission do you have? Is it the hydraulic (old style) or electronic style?
I suspect that the TBI system had a throttle body position sensor mounted on it and that its information is no longer available to be used by the system, which may explain the unusual shift points.
If you still have the throttle body and the plug/harness is still available/connected to the system, then you might try removing the sensor from the body, plug it back in, and set it by hand to an intermediate position in its range of motion so that the transmission no longer 'sees' the situation to be that you are 'flooring' the accelerator pedal. Even better would be to somehow attach the sensor to the carburetor butterfly valve shaft so that it was a variable signal available to the computer.
This is my theory about the problem.
Thanks,
Roland

Follow-up: Sorry to learn that didn't help. Do you know which automatic transmission model # you have?
I still suspect there was a difference in the trans rpm/speed shifting control depending upon the type of fuel system that was used. If you can find out which trans you have then if I have the manual for that set-up with the 318 we might be able to compare that to the 318 you had which had the TBI system and see how these were different. Maybe a Dodge dealer parts counter will have that issue covered in the parts manual IF the vehicle was sold with a carburetor and if not then go back a few years to find a 318 with that same trans and which came with a carb to see how the carb was attached relative to the transmission controls. You may be missing some connection part.