2008 Lariat 4x4
Transmission has irradic shifting into overdrive - back and forth roughly when going between about 42-55 mph. Especially noticeable when going up a slight hill incline.
If I turn the overdrive off when driving around town it's okay, but I shouldn't have to do this - it's pretty ridiculous...
I took it to my local guy who flushed and serviced the transmission hoping this would help, but to no cure. He also reset the transmission computer.
I was told there were no codes in the memory.
Most who ride with me notice the problem... anyone else have this happen to them?

Any solution other than the obvious - by turning the overdrive off?

 

You sure it's not an ignition issue? That sounds a lot like a low grade misfire. How many miles on the spark plugs?

 

Hmmm. I have 180k on the motor. I replaced the plugs at 153500. What do you think?

 

Had similar problem...took Dealer about a week to figure out that it was a misfire on #3 cylinder...new coil made it all better...BTW, that one never gave a check driver light!

That was after changing the transmission fluid, doing a TSB on the transmission, and replacing OD Snap ring which they said was broken (I doubt it was cuz I just had to have that done because I lost OD). All of that was under warranty for me because it was a replacement transmission (original blew up at 51k miles).

Mine was jerking when it shifted into OD at around 40-45 mph (about 1200 rpm)...above that there were no problems.

Hope this helps!

 

That's great information.
#3 location might very well be the issue where I am having a problem. The #3 plug broke last time when being taken out. That was recorded. I have it looked at and have a diagnostic run on it. Thanks!

 

One or more of your coils could be going bad.

 

Wholeheartedly agree.

D

 

From what I am reading, it sounds as though I have one or more plug coils that are going bad. There are no codes being registered. How do I determine which coil it could possibly be without just replacing all of them?
Is there a preference to what brand?

 

Find a OBD2 scanner than can read mode 6 data - that might find the issue. For replacements, use Motorcraft, Delphi, or Denso. No Autozone or other parts store generics.