ok i havent been on here for ages but here it goes with a little background first

i was driving home for xmas friday night (a little over 900 km) and it was around -35 deg C outside, had the front tarped in (area behind the grill but not behind bumper) its a 98 1500, auto

so made it about 600 km on the trip and noticed that it wasent shifting into O/D anymore stoped and checked the oil in the tranny and it was good so being that i was in the middle of the mountan pass at about 1 am i just keeped going the rest of the way without O/D now i went for a drive today and O/D seems to be working again, its about -30 today any ideas what may have caused it to stop working

 

Ryan, good to hear from you again!

If the trans fluid is too cold, OD won't engage. I believe the fluid must be at least 50*F.

Perhaps that 5* switch made the difference. Try letting the truck heat up in neutral to let the trans pump run the fluid thru the rad to heat it up a bit.

 

Too cold. Nothing is wrong. Going down the highway at a fast rate of speed for a long period of time with -38 degree air will really cool that sucker down. Even with the grill blocked the air will run under the truck.

When you drive around town in -30 degree weather the truck isnt getting that much cold air under the chassis, so it warms up enough to allow O/D.

No worries.

 

i was thinking that too but i would have thought it would have done it to start with, not after 600 k

and aim glad somone remembered me hehe

 

There is a customer service bulletin from Chrysler somewhere, was reading it the other day, that states something along the lines of if the computer detects the temperature below -5 degrees, it will not let OD turn on. Squirrels and Monte are right (as if there was any doubt).

Where do you live? In South Dakota, its -10, but after wind chill from our 25-45 mph winds is factored in, -30.

 

Fort Nelson BC Canada...we dont bother factoring in the wind.... it bet with the wind it would be about -45 ish

i just find it funny that its never done it before (ive had it since 01) and ive drove in much colder wether than this for just as much distance or more im not doubting anyone just a little worried about the trip back, also wouldent running with o/d off for a while warm up the tranny again i went over 300 k with it not kicking in at 100kph+ (upto 120ish dident want to rev any higher thow)

oh and when you say -5 are you talking -5 deg F or -5 deg C

 

Fahrenheit.

 

If your worried about it you can change the governor pressure switch. Thats where the temperature transducer is. But i wouldnt worry about it.