I have a 2004 f150 xlt regular cab long bed that is now approaching 900 miles. Everything is great except for an annoying drive line vibration that occurs at about 10 mph and is very noticable at 20-25 mph and again at 40-45 mph. At 60 mph and higher it is smooth as velvet. It is probably most noticable upon acceleration and deceleration. I am trying to get prepared to do battle with the service dept since my experience with finding and fixing driveline problems in the past has not been rewarding. It feels like a drive shaft out of balance or a u-joint that is off center, but who knows? Anyone got any ideas? Anyone got the same problem? The engine is 5.4L and the rear end is the limited slip 3:55.

 

Update. Truck has been at dealer service for 3 days now. They have done all the usual stuff with balancing the drive shaft etc. Today they replaced the pinion and ring gears and all bearings. Just got a call from service that nothing has changed. Still have the vibration. Tomorrow a Ford engineer is going to come by and try to help. Do I hear transmission? This one is eating their lunch.

 

Please let us know what you find. I have a 97 with similar symptoms.

 

Update: Service team from dealer and an area engineer from Ford spent the day scratching their heads and I received a call toward the end of the day that there was a special replacement two piece driveshaft available that would eliminate the problem. This is Friday afternoon March 5. Replacement drive shaft was ordered from Ford for delivery on Monday March 8 and this is supposed to be the answer. I am still waiting for a call from the dealer.

 

I have what sounds like a similar problem and I have yet to resolve. I have a 99 with the 5.4, 3:55 LS and 4r70W transmission. I have already tried, indexed driveshaft with new u-joints, all new trans fluid including torque converter and friction modifier, replaced rear diff fluid with friction modifier. Mine vibrates at 20 and again at 40 accelerating or decelerating, does it in neutral or in 2nd at the exact same speed so rpms do not matter I even killed the engine and coasted down and still vibrated. I posted a similar problem in the transmission forum thinking the problem was the torque converter but I am not sure yet. Does your truck have the 4r70W transmission? Please keep posting your findings.

Thanks,
Dave

 

Just received a call from the Dealer Service department. New driveshaft has been installed and guess what....the vibration is still there. By process of elimination it is starting to look like a transmission/torque converter problem. They are going to call me tomorrow with the next plan of attack. Anybody got any ideas? Right now the dealer is basically replacing the truck one part at a time.

 

Got a call from the dealer service department this morning. They are going to install a vibration damper kit. Truck has now been in for 8 days. If the damper kit does not work, the next area of focus will be the torque converter. This is really getting frustrating.

 

Have you had them check the 4x4 system up front. I just had an issue where my front differential was not unlocking so I was running around with the transfer case in 2hi and the front end locked in.

I do notice that when in 4hi I get vibration from the front drive line. Could it be something in the front end.

 

I took mine to the dealer this morning to have them drive it and see what they thought about the vibration. A service tech went for a drive with me and took along a device that monitored the vibrations frequency. It was hand held and plugged directly into the cigarette lighter. When we got back, he plugged it into the computer and based on the vibrations frequency curve my problem is the tires, said he has seen a lot of vibration problems with the GoodYears.

 

I guess I need to clarify a couple of things. The truck is a 2WD and the tires are Michelins. Tire balance is perfect and we are satisfied that the tires/wheels are not the problem. I am beginning to be concerned that there is a design flaw. This truck is not "rare" but perhaps unusual in that it's configuration is a 2WD/ regular cab/ 8ft bed/ 5.4 L/ 3.55:1 limited slip. You won't see to many of these running around. I live in the Kansas City area and special ordered it from one of the area's largest dealers. They have not sold one like it before or since.

 

Well, I got a call from the dealer yesterday. The truck has now been at the dealer service shop for almost three weeks. Everybody recognizes the problem, and everybody admits that it is unacceptable, but thus far, nobody has been able to figure it out. Dealer is out of ideas. Next step is that they are flying a couple of engineers in from Dearborne on Monday March 22 to try to help. This is what has been done thus far: replace two piece drive shaft, replace differential, install vibration damper, replace all wheels and tires. Anybody got any ideas???

 

i have a 97 4X4 5.4 limited slip, auto, offroad pkg. 108,000 miles
and mine has been doing the same thing , i took the goodyear tires off, put new kellys on and balanced , had front end aligned , new u-joints, new front stablizer links, trans fluid and filter change,new front shocks.checked the front end ,ball joints etc.
left to try is new rear shocks that are on back order and want to try having drive shaft balanced and replace rear diff fluid.
its very frustrating, and hearing the dealer can't find your problem isn't encouraging. please post what you find out next.
thanks

 

casonet.............your 04 is a shaker.....check the other forums sites esp FTE and you will find the problem is getting big with the 04.......ford is scrambling fast on this one........

 

I agree. I have been checking the other forums and the latest theory is a "resonance" in the bed that is observed when dropping the tail gate. I haven't tried that one, and I really don't think that it is my particular problem. Another is the alignment of the transmission with the drive shaft and the differential. There is still another who claimed that his problem was fixed by adjusting the differential ring and pinion gears to factory specs. I really think that each of these could cause a similar symptom but are unrelated. I am firmly convinced that my particular problem is a drive shaft issue even though it has been replaced, but I am not an expert and I have been wrong before. I am not going to worry about it and I am prepared to just live with it if I have to, but I won't be happy. Basically, the truck is at the dealer service center and I told them not to call me until it is fixed. The monkey is on their back.

 

Can you help me with "FTE" . I don't know what you are referring to.