Is it slipping?
 

Hi all. I have a 2004 f150 with the 5.4 4 speed auto and im having a few issues with it. Number one being that when im driving around sometimes at 2-3000 rpms the transmission sometimes acts like it wants to down shift and the engine revs a little bit with no acceleration but then a new gear never engages and it just reengages the same gear. Is this normal? it only lasts for about a second (about the time it would take to shift from 3rd to 2nd) so i dont think it is slipping. My other problem is that sometimes when i put my foot on the gas it feels like the engine and/or transmission has to "catch up" to where the rest of the drivetrain is and so it revs and then feels like it catches.

Thanks!

When's the last time spark plugs and other maintenance was done? I had a problem like this where I thought it was the trans and it ended up needed a new plug and what I thought was the trans slipping ended up being a small misfire.

Dont exactly know. Bought the truck used and she now has 110,000 miles. I havent replaced them and im assuuming that the previous owner(s) didnt have them replaced either. I have heard multiple prices on plug changes. What is a fair price from a local shop (non-dealer)?

I don't know if I'd trust a non-dealer shop to change the 5.4 3 valve plugs unless they have quite a bit of experience with them. Prices vary widely and are dependent on how many plugs they break.

sounds almost like its doing a neutral drop? is the check engine light on? try resetting the computer first and give it a day or 2. GLC is right about the plugs. you HAVE to be watchful of what you are doing. i've always done mine, but i always plan on breaking 1 (and if i don't, it's a much happier day!)

Ok. Thanks for all the responses. I will have to look into prices at my local dealer. Yes it does feel like a neutral drop but only for a split second. No check engine light though. I will get her looked at

be careful with the neutral drop.... those two words have cost me at least 3 transmissions :(

smell your dipstick for your transmission fluid. how does it smell? thats always a quick way to get a basic diagnosis. 110,000 miles and sounds like you its about time for a check up :)