Hello all. I have a 2004 F150 Lariat 4x4 with a 5.4 Triton engine. 189K. It is 10 degF here tonight. Driving home my truck started popping out of gear at about 40mph (2600rpms). Releasing the accelerator, it would sometimes drop back in. A couple of times I had to stop, put it in reverse then back in drive for it to "catch". I seems that if I drop down to (2)low it stays. That got me home. I checked the fluid and it is right on. Any suggestions on what this could be? Expecting about a foot of snow this weekend. Thanks!

 

Likely a pressure issue and it sure sounds like its trying to pump air instead of fluid. If it positively isn't low fluid then maybe the filter has fallen off or is damaged.

Short of low fluid, filter issues or a restriction somewhere, the problem is going to be internal and is likely going to get worse until it stops working.

Of course these are just internet guesses. It's darn tough to diagnose over the internet. I wish I had a way to do it better.

D