Engine/Transmission (1998.5 - 2002) Hunting in Overdrive?

[Joe Mc]

Started this evening - Crusing about 55 mph very light throttle, the tach sometimes creeps up 2-300 rpm then back. You can feel that the trans is switching in and out of OD. Ah, what's up Docs.



Some history: I purchased with 75k from dealer it presently has 110k. No power bombs, no towing anything, it's strictly my daily driver. I serviced the trans (changed fluid +3, filter and added DD pan - followed manual to adj bands) @ 80 and just recently 2k miles ago I changed fluid and filter, didn't adj bands as it was shifting fine.



Suggestions. :{



I haven't checked the trans fluid level yet. Will do 1st thing in the am.

 

[Tom W]

Joe, this sounds like the torque converter unlocking and locking.

This is a common problem caused by electrical noise spikes. You can cure this temporarily by cleaning the battery terminals.



There might be a permanent fix soon. I am trying a box, which I got from Bill Gotthelf, and it has eliminated the problem but it is still early in the test.



Tom

 

[Joe Mc]

Whew!

Tom,



Thanks!Oo. I'll give it a try. Man, that scared the heck out of me. I do want to upgrade the trans as a prelude/pre-requisite to BOMBs, but was hopeful it could wait till after we leave for vacation (driving to Disney in two weeks). I'll try this quick fix out, check the obvious things & keep my fingers and toes crossed.



I'm open for any other input/sharing of experiences you all may have.



Joe Mc.



PS: Just in case - anyone know of an "in my neck of the woods" aftermarket trans outfit - preferably one that knows what out trucks require - installation, set-up, etc. I defiantly don't want any fly by night cheapo deluxe outfit that only deals with stock rebuilds. I'm looking to drop the bombs after the trans upgrade.

 

[WadePatton]

Hunting in Overdrive...

No no no, that's way too fast. It's too easy to hit a bump and miss the game. Turn the OD off and maybe try low range -unless of course you're using a shotgun. :-laf

 

[LSMITH]

Joe, re-calibrate the APPS. I just had to do mine again last night. Unhook both batttery negative cables for a half hour. Connect them, turn the ignition on without starting the engine, slowly put the pedal to the floor and let it up slowly. Turn the ignition off and then you are done. Start and test it out.

 

[Tom W]

LSmith, I'm not an expert but I doubt recalibrating the APPS had anything to do with fixing the problem. I think just removing the negative cables will do the same thing. That's the problem with diagnosing this problem- anything you do can help for a short while. I've fixed it many times ( like the guy who said quitting smoking was easy ) only none lasted very long.

Tom

 

[BillGotthelf]

Joe Mc-Tom's right. Currently we have tests going on all over the country with a new product (small addon box with 3 wire connections) that completly eliminates electrical interference or spikes in the ecm/pcm signal to the transmission. Testors have reported very well and the people who developed the box will be selling them next month. The electrical interference (spiking) occurs from many sources and increases with age. Dodge has a reflash for this but its a waste of time. Some of the aftermarket trans companies are selling a noise filter that helps about half the time. This box is NOT a noise filter, it just fixes the problem if its electrical noise related. Look for a TDR member special for half the price they will be selling them to trans remains, etc.

 

[VicR]

Bill,



Will the box coming on line soon do anything for the 12 valves - I haven't ruled out electrical interference as a possible cause of my problems.



Thanks,



-Vic

 

[LSMITH]

Tom, try re-calibrating the APPS and see how long it lasts. The APPS signal is one of the most critical signals in determining if the TC can lock, stay locked or should unlock. I have not cleaned battery terminals in 2 years, and they are greased for protection is all.

 

[Joe Mc]

Thanks guys. I'll try to recal the APSS and clean and re-lube the battery terminals while I'm at it.



Silly question: I've owned the vehicle for two years and 35k - this has never happened before - does this symptom just come on like gangbusters/all at once?



Appreciate all the great information. Like I said earlier this scared the heck out of me

 

[Justbeamn]

Originally posted by LSMITH

Joe, re-calibrate the APPS. I just had to do mine again last night. Unhook both batttery negative cables for a half hour. Connect them, turn the ignition on without starting the engine, slowly put the pedal to the floor and let it up slowly. Turn the ignition off and then you are done. Start and test it out.

What LSmith stated worked for me. I did the re-flash and had it into the dealer 3 times for this problem {never fixed it!}. After I set the APPS I never had another problem with it.



I ended up fixing it for good by trading it in for a '01 HO

 

[Tom W]

LSmith, I not only recalibrated the APPS, I replaced it ($400) and it didn't help. :{



Tom

 

[BillGotthelf]

Joe-some trucks it gradually builds up over a long period of time others bang happens overnight. If you have a digital voltage meter tap into the tps line and read it at different rpms. Voltage should be steady and not fluctuating up and down at a steady rpm.

 

[Joe Mc]

It worked

I disconnected the batteries for about 4 hours today at work. Before going home greased up the terminals real good w/some white silicon grease and re-connected the batteries. Like Howard said turned key on depress throttle real slow and release real slow. Poof! it worked like a charm Oo. Hope it lasts.



This place is great! Thanks everyone.



Joe

 

[JYaekel]

Recalibration of TPS worked! How long will it last?

I am a the proud new owner of a 98 Cummins. Having problems with the "hunting" syndrome, I decided to recalibrate the TPS after reading this thread. MY problem is now fixed, but I am wondering if it normally comes back after awhile???

Any ideas as to what causes the APPS to need recalibration???

There is a Night and Day difference in the drivability of the truck before and after the recalibration. I could not believe the difference!



If this is not a complete fix to the problem, I am curious about the new box that is becoming available to fix the hunting once and for all. For those testing it, is it hard to install? Has it fixed the problem completely????

 

[TSRAM]

I am having the same problem with the tc locking and unlocking at cruise. The "mystery" switch tells me it's not the tc itself, but the signal. Are the boxes out for sale yet?

 

[TSRAM]

BTW, forgot to add earlier-- Called the dealer today and asked the charge for the reflash #18-02-99 for the truck. They want $65 for a five min. job!!! I'll choose to go another route if possible.

 

[TSRAM]

I have an update since last post. I have been getting ticked off with the unlocking of the tc since monday of this week particularly. I towed our boat about 60 miles each way to Lake Wateree in Camden. About halfway there, the tc started it's I TRIED TO BY-PASS THE CUSSING FILTER again. After talking to the dealer and getting more aggravated, I decided to go and try new batt. 's. It's about time anyway since they were orig. . Just got back from the lake again today for the second trip this week... ... ... . and no problem since the new batt's. I have probably been 200-225 miles since the install and it was cutting up when I pulled in to get them... ...

Draw your own conclusion. BTW the battery tester had shown the 5 1/2 yr old batt. s were good.

 

[TowPro]

Yes click here

Originally posted by TSRAM

I am having the same problem with the tc locking and unlocking at cruise. The "mystery" switch tells me it's not the tc itself, but the signal. Are the boxes out for sale yet?

 

[RJ2]

Does this work on the 12 valves?