Cold Weather Overdrive Problems

[mfburns]

I have a 94 auto and this winter I have been having erratic problems with the engine reving up 50-150 RPM for a few seconds and/or dropping out of overdrive and then back in. This seems to occur at colder temps, 10-25 degrees, and not necessarily in wet conditions. They don't occur in warm wet conditions so I tend to rule out electric pulses. I was contacted by "ICEMAN" who had a similar complaint with his 94 truck. ICEMAN has cleaned the TPS but the problem returned. He replaced the thermostat to get the truck warmer but he can only get to around 160, he can't seem to get the temp up to 190 where Cummins says they should run. He did say that since he got the temp up to 160 he has not had the transmission problem. I have tried running my truck without OD for 10-15 minutes, under the theory that this would raise the oil temp, and when I went back to OD the problem seemed to go away for the rest of the trip home. We both feel that this problem is a result of low transmission oil temps due to the cold weather. Neither of us has tried to block the radiator to reduce the oil cooler effect but agree that it appears to be temp related. I have had my truck to the dealer but no codes so no factory answer.

Does anybody out there have any experience with this problem? Any fixes? Any suggestions?

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94 2500 SLT, AT, 4x2, 100,000 miles, K&N

 

[illflem]

My '95 will do it once in a while also,when it does it will keep on doing it. I finally figured out that if I put it in N for just a short time it will stop for weeks or even months. Found that I can fix it by shifting to N without even stopping. Try this and see if it helps,it could be that most of us AT owners rarely put the trans in N and air pockets develop. What ever causes though,N has worked for me.

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95' 25004X4,AT,Driftwood,Banks Stinger,Warn fender flairs and running boards(work truck)
95 3500,5 speed 3:54,BD E-brake,Driftwood,Banks&Psycotty,34,000 GCVW apple and tractor hauler(works harder truck)

 

[cumminsturbo95]

Sounds like your on the right track, I had a similar problem. First I blocked the radiator 100% this helped a little but did not solve it but does help engine temp. (today it was 66 deg. in GEORGIA AND TEMP. NEVER GOT ABOVE 210 w/ac. on) Next I serviced the trans. & turned up the pressure of the pump + added amsoil atf+4 now my trans shifts much better. Hear a link with info on turning up the pressure on our trans. (very easy) https://www.turbodieselregister.com/ubb//Forum3/HTML/002412.html

[This message has been edited by cumminsturbo95 (edited 01-31-2001). ]

 

[**ICEMAN**]

i am running mine with no fan and the radiator covered and still cant get the engine temp higher than 150-160. i left the transmission cooler uncovered,the cooler stays warm with out the fan and the cold weather surge is gone,,so keeping the transmission fluid warm is the fix,,never a problem late spring through early fall. i have tried 3 new thermostats and temp still wont come up,,,these things are not closing,,sticking open for some reason,,so if we get the engine temp up ,,the radiator will be warmer which will make the transmission cooler warmer. is there any aftermarket thermostats out there??? i tried all the auto parts etc. ,,they can get me one but its from mopar,,done had theirs 3 times. any other way to warm the motor up??mine has always been a cold runnin truck,,i believe the 94-95 trucks are the ones with the cool engine temps. maybe insulate the transmission lines in the winter?? unhook the cooler??i truly believe getting the engine temp up to 180-190 will be the fix though,,wont have to remove the fan etc. #ad


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94 2500 4x4 SLT,auto,183,000 miles,3:54,brilliant blue/silver,tst 250/635 set full forward,star wheel wide open,air box ported,pump turned up 20%,k&n,gauges,cat gutted,
2001. 5 3500 4x4 q-cab slt,auto,6800 miles,3:55lsd,brite silver,tst power max 3 adjustable,3 gauges on the a-pillar,both have 12k hitches&15k's in the beds,30ft fourwinds 5er,(MY RAMS) http://albums.photopoint.com/j/AlbumIndex?u=1360183&a=10142301

[This message has been edited by **ICEMAN** (edited 01-30-2001). ]

[This message has been edited by **ICEMAN** (edited 01-30-2001). ]

[This message has been edited by **ICEMAN** (edited 01-30-2001). ]