That's what I was thinking kind of narrow for a tall tire especially on a full size. I like the way they look.

Hey Evan do you think the 3.55' aren't liking the 33's maybe 3.73's would get you some mileage back.

I know for a fact they are not helping. But I think Bob has 3.55's as well with 33's and hes getting 16 mixed...

Driving habits? Do the egg test and see how you do. Lol just an FYI might want to put something down on the floor for that test. Maybe trans. Or tc.?

I have a vacuum gauge in the cab so I can see when I am accelerating too hard. It almost never drops below 10 inches during acceleration. As for the trans, I am starting to suspect that's the culprit. Sure it shifts fine, but at 200k miles with no rebuild I am positive it is extremely inefficient at transferring the power compared to when it was new.

Yep, I do. Although my tires are narrower. Still shouldn't make that much of a difference though.

I plan on 4.10s soon.

Over the last few weeks I have been looking at 4BT swaps quiet a bit. I am considering possibly doing one for the mileage boost. We have a regular at the station I work at with a 95 F150 SCSB with a 4BT in it and he averages over 30mpg on the highway...

I'd do one in a heartbeat; Except that they're EXPENSIVE to attain. $2-4,000 for just the engine.

I finally got my new / used rebuilt ECU, installed it. I started it and it had a bad miss two cylinders where not firing, I drove it tens miles I stopped at a stop at a light, as I took off the miss went away, and has been running great.

Not sure why the miss had stopped, maybe because it has been running so rich and it took a wail for the rings to seat again.

The ECU was "Learning". Takes 10-20 miles of driving at one time to let them get a good start.

Thank you, for that information, I feel much better now, I thought their might some other problem.

Thank you SideWinder

No problem. My truck did the same thing when I replaced the ECU in it. Ran like CRAP for about 10-15 miles and then BAM! Ran smooth as silk.

If you read this it might make you mad...

https://www.ford-trucks.com/forums/showthread.php?t=1317581

No not one bit. I'm glad people can get good mileage from these trucks. I'm just puzzled how mine does so poorly when it runs so well...

I'm sure it's very very frustrating.. Have you seafoamed it? And cleaned the throttle body

No, no and no... Might have to do that.