x40oz

This may or may not even be an issue, but wanted to see if anyone else has something similar.

While at a stop light, on level ground, I let off the break and the truck will move forward, but very slowly. If on a slight incline, truck will not move at all. At first I thought it was break dragging, but jacked truck up and all wheels spin freely. Also, if I am on a slight incline, put the truck in N and it will roll. So I feel like its not break related. Torque converter maybe? Or maybe nothing.

techrep

iTrader: (1)

Normal...

uzikaduzi

yeah completely normal like techrep said... on an incline, it takes more energy to move your truck. I'm sure you've been on a hill where you had to give it more gas to accelerate or maintain speed than if you were on flat ground. so there is x amount of gas being given to the truck at idle... on level ground, it's enough to move it forward, on an incline, it takes more than x amount of gas to move you forward. you might even get on some inclines that your truck could slightly roll backwards.

x40oz

Im just saying compared to any other automatic I have driven, this seems to have less intention to move forward. Like I said, on flat ground it will travel forward, but at a snail pace.

uzikaduzi

your torque converter is not locked at that rpm (which is allowing your truck to continue to run while you are stopped)... you have larger than stock tires and judging by the size, I'm guessing you didn't re-gear so it takes more power just to turn those tires let alone asking a nearly 3 ton vehicle to idle up an incline.

if it's shifting ok and you're not having any issues with the way it's running, I wouldn't worry about it. i've driven vehicles with auto trans that @ idle will climb an incline and ones that will roll back a little on an incline... obviously when you increase resistance, you need more energy to over come that resistance. even if you are maintaining speed up a hill, you are actually accelerating (because of the new vertical vector... same with turning and maintaining speed) and that acceleration has to come at the cost of energy.

Dirttracker18

This is a heavy truck (even compared to other 1/2 tons) and will require a little more effort to move, thus less roll off when not on the throttle.

x40oz

Still tracking down my low MPG, thought there may have been some driveline or axle drag, but looks like just a big ***** truck. lol

uzikaduzi

how bad is your mpgs? I mean you're leveled and have bigger heavier tires on... if your speedo wasn't recalibrate your trip meter/odometer is lower than it should be so that could make it look worse than it is. I get 12 city 14 highway with the 5.4l 4wd with larger and wider tires than you have.

corey_lax

Another reason they don't move at idle is because Ford set the idle pretty low trying to improve the gas mileage. The truck is barely running at idle haha. People drop 50-100 RPMs at idle and it almost stalls out so the thing is just trying to save gas rather than make "idle power"

uzikaduzi

good point! i hear some stock f150's idle below 550rpms and and apparently it's terrible