Transmission hunts in lock-up

11-23-2003, 09:52 PM's another one. I bought this truck a month ago, 99 Ram 318 automatic 2 x 4. This truck isn't that bad, just has a couple of issues I need to correct. I'm a Chevy man so a Dodge is new to me and I need help/advice. I recently had a complete trans fluid change and within two days it started this. On the highway it'll go in and out of lock-up. The rpm's will go from 1700 to 2000 for a split second, then back to 1700. It might not do this for a few days, then all of a sudden it'll do it once, twice, or several times in one day. Then it'll be a while before it does it again. It does have the correct fluid cause I stood and watched them do the change to make sure the fluid was correct. Anyone have an idea what's causing this???

11-30-2003, 11:40 AM
I had the same problem w/my 99 2500 diesel. Looking on the dodge forum site, i found that the fluid must be up at the full mark. Also, disconnect your battery and turn the ignition on the run position for a period of time. Did mine for about 6hrs. Note: Instead of leaving the key in the on position, with both my batteries disconnected, I shorted the positive terminal to chassis ground to definitely drain any capacitance in the ECM. After about 6-8hrs., the tranny locks up fine.

This resets the computer and it will learn all over the sensors associated with the tranny. I forgot the name of the reset {ATTP } I think.

Good luck and I would try it.
They stated in the forum that you should leave it disconnected with the key in the run position for about 15min or so. I did yard work and farted around so the longer the drain, in my opinion, the better.

12-02-2003, 09:44 PM
Thanks for the tip and reply. I'll sure give that a try this weekend. What have I got to lose! Now, if someone wold reply to my other two postings I'd be a happy camper. One was about how to time a 318 and the other was about a wiring diagram for the radio speakers. I've looked in a few different books but no where is there any mention about how to time this motor. But none state you can't time it either. Never seen a motor with a timing chain that didn't need to be re-timed eventually.

03-15-2004, 03:08 PM
Did this help fix your problem by reseting the computer? My dad's pick up is doing the same thing where the rpms will jump up and down very quickly. It seems to do it a lot when the cruise is set especially. Thanks.

malcolm brumley
03-21-2004, 02:55 PM
If the other fix doesn't work then replace the throttle position sensor. It fixed mine. No more transmission problems.

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