Transmission slipping right after starting in cold weather (below zero)?

Hi all,

Three days ago, I got my transmission and rear diff fluid changed and now I've begun to experience some issues on super cold mornings. The transmission had never been serviced by previous owner and so I did a drain and fill for the first time with 170k on the truck. No signs of metal - the fluid actually looked pretty good.

Two days ago, I started up, waited for it to warm up for about 30 seconds, shifted into R, backed out of driveway, turned so I was pointed up the hill, then shifted in to D (foot on brake). Then gently hit the gas so as not to spin the wheels on the snow.

Here is where the problem begins: My rpm shot up to 2k with barely any gas (not as easily as neutral, but not as much gas was required as drive). The truck did not move, but also d not roll backwards down the hill. I just kept on the gas very lightly trying to bring rpm down as low as possible. After about 10 seconds truck slowly started rolling forwards and 20 seconds later it was normal. At this point the transmission temp gauge read 50% which is normal operating temperature, but it had shot up to this temp from about -5f in less than a minute. Eventually the trans temp gauge came back down to about 20% before eventually rising to the typical 50% highway cruising level again. I should also note that I was hauling a bunch of live sound production gear (roughly 1000lbs total).

Yesterday, I let the truck warm up for a good 3 or 4 minutes and it shifted into drive normally without issue

Today, snow removal service had to plow the driveway and I got a call from my landlord that they were waiting for me to get my truck out of the way, so I was in a hurry. I only let the truck warm up for 30 seconds or so before pulling out and this time the revs didn't shoot up but tires kept slipping in back because of the fresh snow so I went neutral--4hi--drive, and gave it just a tiny bit of gas and it felt like it may not have been in gear yet and it kinda slammed into gear and lurched a little bit. Not super severely but definitely wasn't a smooth transition from being stationary to being moving.

Before these two instances, transmission seemed to be just fine. The drain and fill was done one day before this stuff started happening. I'm thinking low transmission fluid level? Any ideas about whats going on would be appreciated.

 

sounds like low fluid

 

I agree with MUI^^^^^^^

Make sure tranny fluid is at temp (I run truck for 10 minutes, then add at the filler until drain over)

Report back

 

That's what I was thinkin... bought the truck a week ago and am still getting used to it- looked for 20 min before realizing there wasn't a transmission dipstick... And just to be clear, you are saying add ATF at the fill bolt until it begins to start dripping out of the fill bolt after transmission is at operational temp?

Currently truck is at the stupid Ford dealership I bought it from- they are replacing gas tank straps, rear view camera, and doing an alignment all for free. I forgot to ask my trusted private shop to grease all the zerks and retorque prop shaft when I had it in for driveline fluids (too freakin cold and snowy up here to do it in the driveway right now...). When I called them today about the new transmission issues they said they will take a look at it when I bring it back to them to do the zerks and prop shaft. I'll ask them to check fluid level and make sure they do so after transmission is warmed up. If it's fine they'll go through the rest of the drivetrain a second time. After that I will report back. Will probably be two or three days.

 

here's the procedure:

 

https://youtu.be/gMonsduoPao

 

My truck did the same thing last weekend.
Temps were in the single digits and the truck hesitated for about 2 seconds before it started to move. I did not think much about it since it was so cold. It's my first winter with the truck.
I just checked the fluid level a few months ago using the jumper wire method and I had fluid trickling out of the overflow.
Maybe I should check it again..

 

https://www.youtube.com/watch?v=o690DovjDAc

 

When my mechanic did the drain and fill he showed me the fluid. Was not burnt at all. You could tell it was worn a little from clutch packs but there was still a little red in it. Still waiting to get my truck back from stupid ford dealership. . I’m really hoping it’s just a matter of topping off the fluid. My theory is that it didn’t want to engage until fluid had warmed up and expanded.

Do you guys think I should show my mechanic a copy of that Toyota TSB about checking trans fluid levels? I’m concerned because it’s a much more complex process than a simple dipstick check. Or would that be bad form? I don’t want to come across and condescending to the shop...

 

I would ask him how he checked the level first just to see how he checked it . If he tells you he checked the dipstick then you will know he is full of shit.

I checked my fluid this afternoon and it was low about 1/2 quart.

 

Hey Colin!
Did you ever have luck resolving this issue?
I’m experiencing EXACTLY the same thing, after exactly the same service...
However, after having read the TSB, I will engage the thermostat arm and lock with pin. Hoping this gets the fluid level correct, I’m assuming this allows the fluid to properly enter the towing-cooler lines. I’ve thought it was the fluid ever since it started happening, but could not for the life of me figure out how to add more fluid capacity, until I read the tsb.
So thank you!

 

It's possible that the garage that changed the oil checked the level before the oil really had a chance to circulate. Now that it has it's lower than it should be. Also these transmissions use electrovalves to direct the fluid depending on what you're trying to do. For example when you shift into drive the computer opens up a valve that allows trans oil to flow to make the truck move forward. One of these valves could be causing a problem.

 

Easiest way, in a nut shell... (follow the PDF procedure) When the trans is at 115 degrees, add ATF until it weeps from the check port.

 

Hey guys, thanks for the response.

Dr Al: understood; what is the procedure for checking the electrovalves?

We do have a shop snap-on tuner with key inserts, and have been checking the tranny temp with it in order to make sure it is at the proper temp when seeping for fill level.
That has been rechecked after driving some distance. It should be correct.

But since we just did a fluid drain and fill, not a flush, we did not engage the thermostat arm and lock with a pin. Is this incorrect? Should we recheck with the thermostat arm engaged?

Also; engaging tow/haul button seems to remedy the cold slippage. This seems like a good hint, but to what end?

 

Absolutely need the pin in the thermostatic valve for testing... Idk why, but that's what the service manual states.