About a month ago I purchased a used 1999 Ford F-150 truck. It has an automactic transmission and is 4x4. The truck was bought with 34,000 miles on it and so far everything is running just great. There is one thing I noticed though and I don't know if its something that is particular to this type of truck or not so I figured I would ask here...
Whenever the truck downshifts (as the speed drops and hits the 20mph mark) I here a faint click under the center of the truck and toward the front. Also, if I have my hand on the 4x4 stick, I can also "feel" the click when it occurs. I have never had a full size truck before or a 4x4 for that matter so I dont know if this is normal or not. The deal said I could leave it with them for the day and they could run diagnostics on the transmission, but I would rather not have them get their hands on it it if its not needed. I dont want to make a mountain out of a molehill so I just thought I would ask here first. Any comments would be appreciated.

 

If you are still under factory warranty then I'd go ahead and take it in. You don't want it to fail just passed the warranty period. That noise could be simple like a slip yoke needing greased or more complicated like a tq converter or selenoid pack. Better safe than sorry. If you can, take the service advisor or mechanic for a drive so they can hear the problem.

 

I have this exact problem since day one on my truck(99 XLT 4.6l 4X4). Have had it to 3 different dealers on 5 separate occasions and have gotten the same response each time.
"That is a normal operating condition of these trucks". I was like you, this was my first full size truck with a V8 and wasn't sure if it was a problem or not, but it continues to be very aggravating to me. They finally replaced the slip yoke and drive shaft but it still makes that clunk sound. For my truck it is mostly noticable when the trans shifts from OD down to low during coastdown at about 22MPH. It will also clunk as your crusing along in D or OD with light throttle and you take your foot off the gas and then re-apply the gas.
The last mechanic I actually got to talk to about it(not a service writer who doesn't know JACK! about cars or trucks) said he thought it was a programming quirk in the transmissions computer program controlling the downshift. He called it a hard downshift.
He said it wouldn't get fixed until Ford came out with a new calibration code. My cmputer code is ZJP2. I know from Mike T. from superchips that they came out with a new code for my truck(ZJP3) but I haven't the time to go back to ford to check it out.
If you go back to the dealer I for one would be interested in what you find out.

Good Luck

Hobbit


------------------
99 XLT,4.6L Auto,4X4,tow pkge,Factory Side Steps and Mudflaps, K&N filter,BugflectorII, Amazon Green/Silver, Pace Edwards Rolltop Cover.