Engine/Transmission (1998.5 - 2002) Transmission or electrical??? or engine???

[dmaglov]

Very frustrating situation.



I don't want to ask this, because I hope noone is going thru this scenario, I don't wish this upon anyone.



2002 quad 4x4 with the infamous 47RE..... it is frigin hunting in and out of overdrive. Surging, skipping, whatever you want to call it.



I will be on the highway at 100km/h and the truck will go from 1650rpm to 1900 rpm and make the corresponding noises in the engine area.



It will be in the city in overdrive or drive around 60km/h or 40mph and do the same.



I have checked on it and the truck is on it's second rebuild, with an upgraded torque converter. Checked with chrysler, checked with windsor/detroit tech's.



I am a my wits end. Some say check your new torque converter, some say check the harness, check the sensors, tps, thermostat... .



the list is endless. I am having no luck in finding out why the truck surges from time to time. Some days nothing happens, some days you can't drive the rig.



Asking for any assistance in this matter. I apologize in advance gentlemen for the grief and the rambling on.



Doug is frustrated, and has not pulled his trailers in awhile. thanks.

 

[harrisfd]

Hey me too!

Hi, I have an 01 2WD quad with 107K miles and the 47RE that exibits the similar if not the same behavior. In my case it is not dropping out of OD, instead the converter is dropping in and out of lock between 45 and 50 MPH, especially under load. You can test this on your truck by turning off the overdrive and see if the behavior persists. If it does, then it is the converter and not the OD unit. I have a TransGo shift kit, seemed to work fine but there has always been a hesitation when going into lockup, almost like the clutch oscillates during lockup (too much pressure?). Above 50 MPH, lockup is fine. So the question is whether the converter is dying, or is there a pressure problem, or is some component on its way out, or is it some electrical problem?. Isn't there something like a "coast clutch" that has design issues in these trans? I believe these things disengage converter lockup when you lift the throttle, kind of annoying as it drops in and out of lockup on the freeway when you have to "pedal" for those who cannot maintain speed on the hills. Anyone have any ideas?

 

[Fishin Guide]

Might try one of the trans builders.



I got a noise filter from DTT and it fixed the TC cycling issue I was having. Hunting in and out of OD sounds like a broken TV cable, or something wrong int eh valve body.



Dave

 

[LLiddell]

Any time my trans starts shifting funny I remove and clean the speed sensor on the trans. I park on a hill and alot of shavings collect on the sensors magnet. You can wipe the sensor off and hope that it is still good or buy a new one for around $30. 00. Hope this helps

 

[BoeingDiesel]

Read the following... sounds like the infamous T/C lock-unlock issue.



Symptoms : Transmission shifting in and out of gear or TC locking and unlocking under light to medium conditions between 40mph-60 mph. You can very often address many of the above symptoms by doing the following :



Look for any ground straps or electrical connections that may be loose or contaminated. Check battery terminals, look for bad chassis grounds, bad PCM connections , bad ECM connections.



This is a minor electrical glitch that is a pain in the butt and causes many transmission failures.



It can take a good 4- 5 hours to properly go over all the above I have mentioned.



In addition to the above we developed the DTT Noise Filter. We have been testing it for over a year in house and via our dealer base. It has addressed over 80% of the electrical noise we have encountered.



Here is what we found :



Testing has shown alternator noise spikes present in the TPS signal to the PCM. These noise spikes may be responsible for improper operation of the lockup circuit and/or the overdrive circuit. The more load on the alternator ( ie air conditioning , charging a low trailer battery etc. ), the higher the amplitude of the spikes.



The main cause of this is the fact that Dodge has run the TPS harness wiring along with the alternator wires and noise is induced as a result. Testing has shown that the noise is not present in the TPS power supply from the PCM.

 

[RMcKinney]

Hi, Where is the speed sensor located.
Rex McKinney 2500 Stock except deep pan.

 

[LLiddell]

Drivers side on the OD unit. Large plastig socket with wire harness. Easy to check and clean.

 

[cuevas623]

well I am not sure if it is the same as my 99 but I wrapped the alternator ground wire with foil twice and then electrical tape and did the ATS 4th gear hunt fix on mine this weekend and have had nothing but good things to say about it since I cannot remember the sight but search on hear for ATS 4th gear hunt fix and you should find it. my truck was doing the exct same thing

 

[SWiller]

Sounds like your TC is unlocking and locking, I had the same prob with my 99 right after i bought it. so i had the trans rebuilt with suncoast TC,VB, and 5mi later it did the same thing... long story short every time i disconnected the battery's it would reset the tcm and work fine for a few miles, so i replaced the tcm on the fire wall and was great till i sold it.





good luck.

 

[SnoKing]

Clean all your grounds (many), put on the DTT noise filter, and foil wrap the ground between the passenger battery and alt. You will be good to go. SNOKING

 

[Huff N Puff]

Start by cleaning your battery cables.

Then test your batteries,Your batteries and good grounds clean up Alternator noise. Which can drive your processors crazy. The sensor ground behind the starter can also cause erroneous sensor inputs,to the processors.

 

[AllianceDiesel]

what everybody is saying is pretty much what is going on, your getting some electrical feedback on your tc wiring causing the computer to do some crazy stuff, check your grounds and I have heard of people wrapping the wiring out of the alternator