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Hi all. I've an '08 F150 with the 5.4 liter Triton engine. So I'm about to pass a car on the highway, I stomp on the gas pedal, and I get what feels like an engine buck with no increase in speed. Gave up on the passing. Tried passing another car later, same thing. Changed the fuel filter, took it on the road for a road test, and the transmission shifts smoothly when stomping on the gas pedal and speed picks up fast. Great!
Tried the same thing on a gradual hill yesterday, and same original problem again. Tried it again on the same hill today, and it seemed like the transmission couldn't decide which gear to step down to when stomping on the gas pedal. It finally shifted to the lower gear (after a very short moment) and the fast speed picked up just fine and the truck moved along no problem.
Otherwise, under normal driving, the truck runs just fine. This happens only when putting a heavy gas demand on the engine to pass.
The only thing that's different in the last little while is that I changed the spark plugs on my 5.4 liter with Champion equivalents. The engine has 86,000 kms (53,750 miles). Any ideas? Thanks.
Its the kind of lame 4 speed trans that our trucks have in them that holds back the 5.4 a bit. I noticed passing gear sucks at some speeds and kicks *** at other speeds. The six speed trans that the 09+ F150's have is the only thing about the new trucks I wish mine had.
Curb Weight
Gearing
Lack of Aerodynamic Efficiency
Summary = It's a truck; same story with my Jeep - heavy brick on wheels.
If you want passing power, then you'll want a sports car and I'm not being a smart a**, just giving you the blunt truth. Short of re-gearing, engine modifications, and/or tuning; the behemoth is not going to be blowing anybody's doors off from a rolling 40mph+.
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2007 F-150 FX4 Screw, 6" ProComp Lift, 35" Good Year Duratracs, 17" XD Addicts, Rolling Stock Power.
Hi all. I've an '08 F150 with the 5.4 liter Triton engine. So I'm about to pass a car on the highway, I stomp on the gas pedal, and I get what feels like an engine buck with no increase in speed. Gave up on the passing. Tried passing another car later, same thing. Changed the fuel filter, took it on the road for a road test, and the transmission shifts smoothly when stomping on the gas pedal and speed picks up fast. Great!
Tried the same thing on a gradual hill yesterday, and same original problem again. Tried it again on the same hill today, and it seemed like the transmission couldn't decide which gear to step down to when stomping on the gas pedal. It finally shifted to the lower gear (after a very short moment) and the fast speed picked up just fine and the truck moved along no problem.
Otherwise, under normal driving, the truck runs just fine. This happens only when putting a heavy gas demand on the engine to pass.
The only thing that's different in the last little while is that I changed the spark plugs on my 5.4 liter with Champion equivalents. The engine has 86,000 kms (53,750 miles). Any ideas? Thanks.
No no, guys. It's not because the truck doesn't pick up speed like a racing car. I've always been able to get speed right away as soon as I stomp on the accelerator. What I'm talking about here is what seems like a lack of gasoline perhaps getting to the engine when asked for it. Like I said, I've changed the gas filter thinking it might have been plugged. Something is keeping the truck from shifting to the lower passing gear sometimes and getting the revs up needed to pass. It feels like it shifts down, but then it kicks/bumps/hickups. It simply will not gain ANY speed, and the engine sounds like it's flubbering. Doesn't happen all the time but has been lately. Today, it shifted to a lower gear, then immediately to the upper gear, then back down to the lower gear within 2 seconds or so. At that point, it picked up speed like crazy.
Sounds kinda like my '98 with a 4.6. Does fine normal running around, but passing one time seems different then the next. It will build revs, but not really try to pick up speed, then the next time it will be fine? With my older one I just don't pass very often, it probly could use a new fuel filter tho. If my '08 was doing that I'd be on the hunt for answers too. I'm gonna keep checking for when you find the answer so I can try it on my old reg cab.
5.4 lacks power when passing. Why?
Linear Mode
