I recently purchased a 1998.5 (24v) Dodge 3500 dually with the Cummins/Auto. The truck has the full Banks Power Pack on it. The power is nice, but I am a bit concerned about the auto trans.

My concerns appear to be warranted as the trans has begun hunting for the correct gear between 1100-1400 RPM at about 41-46MPH. If my foot is in it, it won’t hunt. Or, if I am just cruising with almost no throttle, it won’t hunt. However, in just general cruising (about 80% off the time), it will hunt around.

I called Banks to ask their opinion and it just turned into one big sales pitch. I have been told that I may need to have the trans reprogrammed by Dodge due to a service bulletin and that my TC may be on it’s way out, or I may be having a vacuum issue. I just wanted to get some opinions off this board.

Does anyone know of a good So Cal trans specialist I can take this to?

Thanks

Miles

NOTE – I know someone recently posted about the Dodge trans hunting but I couldn’t seem to find it in the pages or using Google.

anyone?

Miles? Trans stock?

With the info you posted I'd say you could either try upping the line pressure a little or just give up and get it built. The fact is a stock trans is not gonna work well with a modded motor. Just can't handle the TQ. Mine does the same thing. I'm just living with it until I can get it built.

oh my fault. Yes stock trans and about 130k.

I know its expected useful life is nearing its end with the motor mods etc. so I am trying to see if I can get a reasonable fix until I can afford to build it, if necessary.

Sounds like the TPS is going out.

I guess I should elaborate!

TPS Throttle Position Sensor. Mounted on the motor hooked to the throttle and tells the ECM (Electronic Control Modul )how hard your mashing the go pedal. The ECM tell the tranny what gear it should be in based on several things. Engine RPM, Ground speed, throttle setting, Ect Ect...
If it doesn't get good info, it hunts for the right gear.

Clear as MUD?

Would the TPS cause the trans to hunt/surge only in that range of speed/rpm?

Thanks

If you saw how cheezy that part is you'd understand. It's nothing more than a big reostat with a wiper contact that rotates on a shaft. It spends a lot of time in the 40 to 50 mph range and so that is where the contact wears the coils at first. Once the coil is worn down it breaks the tiny wires and the wiper contact looses connection and the ECM doesn't know what to do. So it hunts for the correct gear.

As fine and sturdy as the engine is, the electronic contols and sensors are on the other end of the stoutness spectrum. Go Figure.

It's not a real expensive part IIRCC. Depending on your source, less tha $200.
I've seen some sell for $150 ish.

TDR (Turbo Diesel Register .com) has volumes of pages on it.


SSSRodeo

a diesel with a vacuum issue, ha ha ha.

Could be either the TPS/APP itself going bad, or I have heard that some of the 24valve Dodge's have problems with electrical interference on the unsheilded TPS/APP wires. The TPS/APP wires it seems run near the heavy duty alternator cables or something of that sort, so the alternator windings induce EMI (electro magnetic interference) on the TPS wires and the ECM/TCM gets these little blips of "static" on the TPS wires, and therefore thinks you are jabbing the pedal really quickly and erradiccally. So therefore it unlocks and locks the TC randomly and sometimes "hunts" for gears....I think there may be a kit out that sheilds the wires or reroutes them but im not 100% positive...??