newcoyote

Hi all. First off, I understand diagnosing here is not as easy as just listing some symptoms and getting an accurate answer. Just trying to get an idea.Of course if you DO know, great. I've seen it happen. I have a 2007 F150 FX4 Supercrew 5.4. I don't know that there are any transmission options but it's Electronic 4 speed auto O/D. It has a leveling kit with 35X12.50R20LT. I bought it last Sept from a reputable dealer and it was in very good overall shape. One thing I have noticed and is of concern is what I think is a transmission issue. The truck drives normally for the most part. Accelerates fine. In certain conditions I will get some shudder or hesitation just before shifting. This only happens if the RPMs are low and a shift change is about to happen. Accelerating but slowly. The best example I can give and this is when it is most likely to happen. If I am following someone and they are going slower than I'm cruising. So I have to give just enough gas to maintain speed but not actually accelerate. The transmission will feel like it is shuddering/skipping or hesitating if the same amount of light power is applied. Taking off the gas or giving power enough to shift makes it go away. It is not intense but noticeable. I don't know if it is related but sometimes I will also hear a metallic rattling at very low or near stopped speed,sometimes at a complete stop. Pulsing the bake a bit kind of dissipates it. Nothing noticeable is going on with the shifting at this point. Any ideas what I might be dealing with here? Any more info required? The condition has not changed since I noticed it. Not gotten worse or better.

fordsonly

I suggest you search torque converter shudder for these years. Very common our expedition had it and my buddy's 2005 has it now. I do not think the sound is related though.

bullwinkle89

I test drove a real POS 2006 f-150 FX4 the other day and it had a similar issue. I coulnd't tell for sure if it was an engine or transmission, issue, however. It happened in 2H, 4L and 4H so I attributed it to the engine mis-firing at low RPMs. With 123k miles on it, the main suspect would, of course, be plugs that have yet to be changed. I'm now wondering if it was instead a torque issue.

fordsonly

happens around 45mph on slow upshift. Floor it and it goes away ,or if you keep steady acceleration it wont stop.

matthew12101

This sounds exactly like what was happening to my truck. Cruising at about 45, I would accelerate slowly and several bumps or slips would occur. Drove me nuts and cause me to accelerate through it. Eventually my transmission failed in that range and forced me to have a rebuild. Not the best case scenario...

jamie930

Sounds like the classic misfire for the 5.4

How many miles do you have on the truck and how many miles on the plugs?

newcoyote

The truck has 160 000 KM (99 000 miles). Unfortunately I don't know the last time the plugs were changed. I bought it second hand. The previous owner seems to have taken very good care of it buy if he didn't, they're due.

RichP9

i would start by changing the plugs, but do your homework on them first you might want to bring it to the dealer and have them changed, it is pretty common for them to break off in the head. i had mine done at the dealer for about $400 and even though they didnt break any it was worth the piece of mind.

roth214

Change the plugs, perhaps the coil packs too. Mine did that..changed plugs and totally gone. I didn't believe it either. Was 99.9% sure it was tranny issue and it wasn't.

mmdutcher

Yep, change the plugs as it seems to be a misfire.