2008 Ford Expedition stuttering while driving at 40-50 mph

[fuzzmanmatt]

Ha! I actually am having this exact issue, decided to see what info I could find.
It's like a surging, most noticable around 1700 rpm, it dips and then catches up.

My first thought was TCC solenoid, since the issue goes away when overdrive is turned off. It COULD be an ignition issue, but I've got a reman engine with new coils, so I'm leaning towards transmission. I put a Motorcraft MAF in last summer after getting codes for that. I'm not opposed to trying the friction modifier, honestly. I just don't want to drop the pan in this snowy weather.

Sorry for resurrecting an old thread, but I can at least say I didn't start it!

 

[amoreno]

Sorry if I'm posting this too late:

I brought my '08 Expedition (180k miles) to Brian Laskowski's shop (https://www.youtube.com/@FordTechMakuloco) for a rumble strip sensation when going up hill at around 30mhp/1800-2000 rpm. This is what Brian said:

"I did duplicate the rumble strip sensation and sadly it is coming from the torque converter. For this concern I would definitely perform a fluid and filter service with an extended drain and retest from there along with a friction modifier additive before we just condemn the torque converter completely. Transmission fluid and filter service with additive runs $210"

Brian changed the ATF, and there was no need for the friction modifier additive. I have put 20k miles on it, and the transmission is as smooth as possible, no more rumble strip sensation.

If this is the same thing you've been experiencing, you know what to do now.