Hey Guys,

I just bought an '04 newer style F-150 ecsb lariat with the 5.4 and 100K miles. It is a nice truck and very clean.

Through hours of searching I saw a couple threads possibly on what I am seeing and want to run it by everyone to confirm my thoughts or redirect them. Or just tell me what to search for!

This may be a non-issue and normal for this truck (I came from an '05 GMC sierra and '01 S10)?

The truck seems to make good power throughout the powerband and rides well except for when I sit at a stop sign/light and go from 0-1500/1800 RPM. The truck doesn't move much (or rolls backward) until the higher range of that. The throttle responds and definately is moving with my foot's input (so I don't think TPS); and RPMS are moving up with the input (so maybe not MAF?).

Would this be a function of the torque convertor and considered normal for these trucks? My chevy/gmc would accelerate proportionally to the rpm from idle-whatever ; whereas, the ford seems to have that "lag" from 0-1800.

 

Bump! Anyone? Bueller? Bueller?

 

If it rolls backwards while in drive , there is a problem with the transmission

 

Mine does none of that takes right off. sounds like you need to have the transmission checked out. might be a little low on fluid.

 

Thanks for the replies. I'll start here.

 

Yes, the first thing I would do is to read the book and get the procedure for trans fluid check and do that. Check fluid visually and by smell. If it looks good but is low, it could act like you said, but it would have to be quite low. Then I would be concerned about why it is low. If it appears to be good and is at the correct level, then you have to troubleshoot that system including the torque converter and electronic controls. If it is not transparent/red, but looks cloudy/gray, and maybe has a 'burnt' smell, you could be looking at a trans overhaul.
In my experience with automatic transmissions over the last 50 years, it should creep forward at idle and accelerate with any throttle whatsoever. Requiring 1800 RPM to move (if I'm reading your post correctly) is a serious malfunction.