I wasn't really sure where to post this question....

I have a 99 F150 4x4 XLT 5.4 and everytime I start it or just turn the key without starting it, after about 3 or 4 seconds I feel a thump underneath the floor board. Could this be the fuel line building pressure and maybe a fuel line hanger is missing??? Anyone else ever experience this?

Also, another slight annoyance.... When I'm driving down the road with the window down I can hear something that sounds like a small chain rattling. A real high pitched ringing? It sounds like its coming from the driver's side. At first I thought it was the mirror, then the break pads... but it's not that...??? Ideas??

Thanks in advance!!!

Roland

 

No idea about the thump under the floor but the "chain jingle" you describe sounds just like what I experienced. Mine turned out to be the spindle nut retainers. Some have said just tighten up the pins to fix them but I went one step further and put a dab of form a gasket inside them to cushion them and tightened the pins. Extremely annoying sound isn't it?

 

I believe that thunk is a part of the transfer case self-test. I think it engages something and disengages it just to make sure it works. I'm not positive, but mine does both things you described... it's going into the shop in a couple of weeks, and both of those are on the list. I would think that the clunking is normal, but my 97 never did it... maybe something they didn't include on the early ones?

-Joe-

 

I've never noticed it, but doesn't the ABS go through some kind of self test at some point after you start the truck up?

 

Thanks for all the replys!!!!!!

t_daughrity - the spindle nut was it... I removed the key and the noticed inside the nut was some goop.... must've come that way from the factory??? Thanks for helping fix that annoying sound!!!!

Roland

 

No problem kruck, I know how annoying that sound was when I couldn't find it. Mine had the 3 dabs of whatever in there too, stuff just didn't last long. Pretty poor idea if you ask me. What ever happened to the hole in the spindle with a crown nut that the cotter pin went through? Pretty foolproof. Still no idea on the thunk, I have never noticed my 97 doing any kind of self test or anything.