So I am experiencing a new problem and I've done a little research but I wanted to see what you guys thought. The problem is that when I'm cruising at about 35 or 45 mph the throttle acts funny. The RPMs start bouncing slightly and the throttle vibrating under my foot. Its almost like its running to rich. If I turn the overdrive off I don't have this problem. It was suggested to me that the overdrive was the problem and it could be a vacuum line on the trans. or an overdrive solenoid. Which could be external or internal, I look around on line and found this big explaninatin about my trans.


First, understand that the 46RE is an electronically controlled, hydraulically actuated transmission.

There are a number of things that can affect a no 3-4 shift:

*Assuming that the OD Switch on the stalk is off, the switch could be defected causing the OD circuit to be defeatured. This does happen!

*Overdrive circuit fuse is open.

*The overdrive switch circuit either open or shorted. Check the connectors at the transmission for corroded terminals. This is very common on older RAMs.

*Incorrect outputs from the Distance or Coolant Sensors. A punky Distance Sensor can caused a weird collection of symptoms, including no 3-4 shift. Also, remember that the 46RE will not shift in to fourth gear until the transmission fluid reaches a certain temperature. If the coolant temperature sensor is bad you will not get a 3-4 shift. If this problem is recent to the winter weather, this should be a prime suspect.

*Incorrect output or intermittent output from the Throttle Position Sensor. On Dodge trucks the Throttle Position Sensor can cause all kinds of problems. Maybe even global warming!

*The Neutral Sense circuit to the PCM is open or shorted.

*The Overdrive Solenoid either shorted, open, or weak. On older 46REs the solenoid plungers became partially magnetized over time causing inoperation.

*The Overdrive Solenoid feed orfice is clogged in the valve body. A very common problem on vehicles that DID NOT receive a reqular transmission filter and fluid maintence.

*Low hydraulic pressure. This can be caused by a number of things, too. But before you suspect the pump I'll bet that the Anti-Drain Back valve in the transmission line is clogged. Some shops clean them, but I would recommend replacing it and changing out the fluid.

*Failed Overdrive Clutch. Unfortunately, this is somewhat common in earlier years, especially vehicles that towed heavy loads or were used in hilly country with the vehilce in overdrive.

*Failure of the Overdrive Piston Seal. Usually not a problem unless very high mileage or Dexron-Mercon fluid was used.

*Clogged Overdrive Check Valve. The result of dirty transmission fluid.

*If this transmission has been "overhauled" or "rebuilt" by an independent and they DID NOT use a Mopar transmission overhaul kit, it is very possible that Overdrive Piston has the incorrect spacer installed.

*PCM failure (the least likely).

My muffler is totaly rusted out and useless so I was thinking maybe even the catalytic converter. I'm at your guys mercy what do you think?

 

Is it throwing any codes?

 

It sounds like a noisy TPS. By defeating the O/D, you'll be driving with your foot in a different position to maintain speed. Different throttle position = different TPS position.

 

tip - turn OD off at slow/moderate speeds under 55-60. the OD locks up way to soon and drags the engine.

if your RPM's are bouncing your torque converter clutch may be locking/unlocking or slipping, and/or you may be shifting in/out of OD.

 

I'm not getting any codes from it and it doesn't happen when the O/D is off. I'm really hopping its not a torque converter...