At 3,500 miles, my supercrew 5.4 developed a serious vibration that seems driveline related. It only happens between 1600 and 1800 rpm's and it can be really felt through the gas pedal. I checked to see if anything was loose underneath. The drive shaft has some play in it, but I don't know if that is what it is. Odd how everything under the truck is nicely painted/coated except for the drive shaft. One big chunck of rust! Anyway, I take it in for service in two days- we'll see...

 

Hey Rocket that is exactly when mine does it. Im still waiting (2 weeks now)for a new driveshaft.

 

Mine has a very minor vibration in the gas pedal from 52 to 58 mph (I forgot the RPMs). Anyway, it stops when shifted out of OD and when shifted into neutral. This makes me think it is a transmission issue. It has gotten better over the past several months and is barely noticable now though.

 

I too have the vibration in the pedal, but I like it to be like that. It makes me feel like I am still driving a TRUCK not a grocery getter with the back roof cut off. Long live a rumbling V8!!

 

Reblance your tires as many times as you want, new drive shaft and antivibration kit will not help if you are having the vibration between 45 & 65 mph. The vibration can be felt in the floor, seat, center console and doors. A Ford field engineering said my truck was normal but my dealer service manger said the 1 in 4 new trucks do vibrate. The only solution is make Ford buy back the truck by going to the Dispute Settlement Board.

 

I don’t have any vibrations that seem out of the ordinary. Smooth and quiet. I did have one bad tire that was replaced around 1,000 miles, it had excessive road force.

 

I got my truck back from its 5,000 mile service today. The dealer tried to tell me that the vibration I have between 1600 and 1800 rpm's is due to the aftermarket air intake system that I installed. I wondered how long it would take for them to start blaming aftermarket parts for completely unrelated issues- apparently, it was the second time in!!!

It does it the worst when the engine is really under load- with the cruise set and it doesn't downshift from overdrive when going up a hill and it creeps down into that rpm range.

Superchips is coming out with their 2004 programmer in mid July- I'm going to see if that has an impact before I take another run at the dealer with this deal. With any luck, proper engine/transmission management from correct programming will prevent the damn thing from lugging the engine into this rpm range to begin with...

 

If the aftermarket air intake system is causing the vibration between 1600rpm and 1800rpm, you might have a serious underlying problem that could never be corrected satisfactorily. It almost sounds like it time to invoke the “Lemon Law”.