transmission slip

[massram21]

sometimes transmission slips when cold on first drive of day only first gear , anyone else have this issue ,runs great all the time otherwise ,don't know if I should worry about it

 

[Rick3478]

It's pretty common in many transmissions for torque converter lockup clutch to hold off engaging until the transmission warms up a bit. This may help to warm the fluid and also protect the transmission from erratic shifts that might happen when cold. Anyone know if the ZF incorporates this strategy? If something is actually slipping, that could be a problem.

 

[kapinallinen2]

First thing I would do is check it for proper fill level.

 

[stevj]

Does the torque converter lock up in 1st gear?
I've noticed a delayed and occasional rough shift to 2nd gear when the transmission is cold.
Once it's warmed up, though - all smooth!

Steve

 

[Dewey]

My last three 8 speeds have done that. Only happens when I tap the gas hard while rolling slowly and then let off quickly. The motor revs higher slowly winds down with no obvious load on the drivetrain. I just assumed it was normal and just a cold torque convertor. No issues otherwise. I can gas hard from a standing stop when cold and no problem.

 

[JayBee2019]

Are you sure it’s slipping in 1st? Mine seems to want to stay in 3rd a little longer than it should on that first cold stop and go.

 

[Darksteel165]

sometimes transmission slips when cold on first drive of day only first gear , anyone else have this issue ,runs great all the time otherwise ,don't know if I should worry about it

Happens to me every single day since I owned the truck.
I need to either use very little gas or lots of gas.
If I shift it manually (not gear limit) it shifts gears fine, so it's just the tranny being stupid as hell.

If I let it sit for 2-5 minutes then it's fine.
Only on cold starts, but it's not a cold problem because if I do a cold start where fluids are 70 degrees it still happens, and if I do it on a day when fluids have been sitting to 20 degrees, and warm up to 50 is fine.

I did drain out some transmission fluid as I was a bit overfilled from the factory, I still might be but it's a pain for me as I don't have level ground.

 

[BowDown]

Mine did it last week when it was in the 20°'s here. Wasn't really the trans slipping but the torque converter allowing slip due to cold temps. Once the fluid was 50° or higher, it drove normally from a stop

 

[RAL]

ZF transmissions modify shift patterns when cold to warm the engine and catalytic converters more quickly. It is part of the design. Just drive easy when it is cold. I am very careful about not doing anything extreme until the transmission temp hits at least 100 degrees.

 

[ws6guy]

Jumping in here on this. Do you all notice the torque converter locking up? On my last 2 trucks (4 speeds) you could tell when the torque converter locked up as it almost seemed like it was another gear when it locked. The only think I notice on the Ram is occasionally in 2nd or 3rd the RPM's will drop a little before switching to the next gear. Most of the time this isn't even noticeable unless watching it closely. Most of the time it seems like the converter is locked based on how the RPM's respond to application of the throttle.

I guess it would make since that converter is locked a lot more with an 8sp vs a 4sp since 8 speed can just down shift to get in the correct RPM range instead of releasing the converter.

 

[RAL]

I cannot say that I do. The transmission is not as smooth cold as it is when warm (exceptionally smooth) but this normal.

Candidly, don't make the mistake of over-thinking this. If there is an issue with the transmission, there will be an error code that displays pretty quickly. ZF has had that capability for 30+ years. And if the truck is new from the factory, the chance of it being over or under-filled is really quite low. And finally these transmissions have been in production for 10 years (maybe more) and are used in many vehicles made by Chrysler, and other manufacturers as well. They are very durable and reliable units. Not to say that problems do not occur, but if there are no error codes and the truck is shifting up through the gears, I wouldn't over-think it. Let it do its thing and drive the truck. You have a 5 year power train warranty to figure out if there is something amiss.

HTH.

 

[Darksteel165]

ZF transmissions modify shift patterns when cold to warm the engine and catalytic converters more quickly. It is part of the design. Just drive easy when it is cold. I am very careful about not doing anything extreme until the transmission temp hits at least 100 degrees.

These transmissions shift like crap on a cold start without waiting. It's got nothing to do with the temp of the oil because I can get it to shift fine on days when the oil started out "cold" 5p degrees warmed then days I let it idle before driving and it's fine.
If I shift it manually with my paddles on a cold start it shifts fine.
Been like this since the day I got it.

It jerks the truck forward and back instead of shifting if I just put it in drive and move waht I could say a medium speed. Very slow it's fine (enough to get rear ended) and nearly WOT it shifts fine both on cold starts.

I believe it's just how these transmissions are, it's annoying but I don't think anything is breaking. I've been told "it's a thing they shift sloppy when cold" whatever that means.

 

[massram21]

Are you sure it’s slipping in 1st? Mine seems to want to stay in 3rd a little longer than it should on that first cold stop and go.

just on the first 20 + - of seconds of driving , revs up a bit then runs great

 

[RAL]

I just drive very slowly when it is very cold and the driveline is still at air temp basically. I also turn off the auto stop start functionality until the transmission is at 100 degrees.

 

[TheWaterman83]

Mine behaves the same especially when cold, delay from 1st to 2nd shift. It seems to be normal behavior.