Help, I need to pick your brains on this issue. On my 05 screw lariat 4X4, when I am stopped at a redlight on a hilly slope and I go to takeoff the truck will roll backwards. It happens when my foot goes from the brake pedal to the gas pedal and of course is worse when there is more incline.

My previous 99 f150 wouldnt do this it would stay put and other vehicles are the similar. From what I know that auto trannies are built with a one way roller type clutch to prevent rolling backwards on hills. The 05 feels like I have to drive it like a manual.

Anyways, I am looking for your input whether you have a 99-03 or 04 to present f150, so i can figure out if mine is normal or i should have it look at before my factory warranty is up. Any info would be appreciated.

 

have u checked ur fluid level? how steep of a hill are we talking?

 

Yah, Ive checked it many times, level ok and still a good red pinkish color. it only has 35,000 miles on the truck. There are many good hills in town and i am not sure of what the actual grade of these hills are. but some are steep maybe 20 to 30 degrees or so. In other words i would not ride a skateboard down any of these streets even if i was good at skateboading!

 

what is your idle rpm in drive, and how high can you stall it to with ur foot on the brake in drive?

 

Today I was stopped on an incline, and when I took my foot off the brake to hit the gas I rolled backwards a little bit but it wasn't anything huge.

 

Built5.4, you have some though provoking questions. I wasnt sure so I went out and tried it. According to the factory tach, idle in drive is about 550 or so as the line markers suck. Trying the stall it was about 2,000 rpms.

 

yeah little inclines are that bad, but i quess my point is it could also be a safety issue as well. I would rather not roll over that little honda that has her bumper a foot from mine, or what if i was pulling a trailer with no trailer brakes it would roll even further. I shouldnt have to power brake on a hill.

 

Hm. that seems about normal, but if your really at 550 idle rpm, that could be why.

 

My friend's F150 which is a '03 will stand on a hill and he doesn't have to worry about rolling backwards - ever.

I *think* his drive idle is 650-675...

Your idle sounds low.

 

I was trying this out on my truck the other day on a moderate incline, it didnt roll back at all but that could be because I got my idle about 150rpm+ from stock.

If its really annoying for you, see if the dealer might help you out.. maybe a pcm flash or if they can bump you idle up a bit

It will roll on very steep hills tho...

 

I've only heard this problem from the 04+ though

 

I've read a few threads that mention that the 2004+ F150's can have either a 525 RPM or 650 RPM idle speed, depending on the PCM calibration. Those who have the 525 idle speed will probably roll back. Those who have the 650 idle speed (like me) can stand still on a very steep incline and still not move backward.

The trade-off is that during very low-speed driving (traffic), I'm on my brake pedal more than most. I see other 2004+ F150's that just coast right along with out the brakes, whereas I'm on them almost all the time. When I take my foot off the brake pedal, I get up to 30mph in no time.