My 2008 f150 scab 5.4 3.73, has had a vibration since new. You can feel it in the wheel and floor, it shows up between 70-85km.At 78kmph with the ford tech meter there is a vibration at 1440rpm and 880rpm, the 1440rpm will go away once you leave the 70-85km range.

Things we have tried....

changed wheels with another new f150
switched drive shaft with another new f150
checked rear end backlash


any ideas.....Thanks...

 

Well I'm glad to hear they are working with you, as they should on such a new model. I'm having vibes on my 05 FX4 when accelerating 55-65 in 3rd. gear in the seat of my pants which clears up when auto changes into 4th at around 65 mph. Mine feels more like driveline issues. Since you feel yours in steering wheel my guess would be rotors, maybe warped. Like I said I'm no expert but I have had a car in past with warped rotors that you could feel in the wheel and floor. Probably not your problem however just trying to input something on my part.

By the way, what's a ford tech meter? Reason I ask is I carried my truck into dealer to recreate my vibe and this tranny guy said he didn't even feel it. I couldn't believe it. Maybe I should request they use this tool to help them diagnose my issue, though I feel for sure my problem is in the driveline even though they don't want to admit it. Good luck with getting that fixed to your satisfaction. You deserve it as I can surely relate. I just bought mine and after 2 weeks this all started and it's causing me lost sleep at night.

 

The meter measures vibration , it measures vibrations in either hrts or rpm.The tech was not using the current generation of meter. It can measure more then one vibration at a time. The sensor is on a 10ft cable and attaches with a magnet.

My vibration is in the drive line (I think), We also shimmed the axle with a 1-3 degree shim, the one degree shim took the oscillation out of the vibration, the 2 and 3 degree made the vibration worse at the 70-85km range.

Could the vibration be coming from the transmission side of the drive line.....

 

Other things to do/try.

Vibration damper
check pinion angle
make sure tires and wheels are road force balanced
index the driveshaft 180 deg

 

Clearly NOT saying this is your problem but on my '99 I had a vibration from the day I drove it home from the dealer new. It was between 1850 and 2000 RPM. It would do it sitting in park or neutral or on the freeway, all at that speed. I figured it had to be the front pump, but possibly the TC. Ford put their (graduated in the bottom half of his class) engineer on it and did a bunch of things that made no sense and did nothing. Replacement of the TC with a "remanufactured- ha ha" did nothing. Finally when they put a "remanufactured" trans. in my brand new truck, the problem was gone, but I was left with a rebuilt trans that looked like it came from a 1910 tractor before it was rebuilt. Long story short, it finally did get a new trans., no thanks to Ford, after it sat gathering dust in the dealership for 6 weeks. :o

 

That sounds like a transmission problem. If you downshift to 2nd does the vibration go away at the same speed?

 

The ford tech posted my vibration problem on their forum with ford, they came back saying to check the backlash on every second tooth. The tech stated the backlash could be between 8-10 thousands but not out more the a two thousands. He got readings between just shy of 8 to just over 12 thousand, so that puts it at twice recommended.

The tech is posting the results on the ford forum, and waiting for there response before changing any parts.


Hope this is it............

 

New ring gear installed, no more vibration.

 

Hey basicplus,

Ive been troubleshooting a vibration as well.

Was your vibration felt just at the 70-85 KMH range or did it continue up to highway (120 KMH) speed?

Was you vibration intermittent or was once it started it stayed until you slowed down?

And what is a ring gear? Where does it install / belong?

Thanks

 

Ring gear as in ring and pinion are the set of gears in the differential. They're only sold as sets since they're lapped together, so they likely changed the pinion gear as well.

 

Hey basicplus,

Any progress on the vibration you felt?

Ive changed tires, tie rod ends and shocks and mine is still there!?? Dont know what else to do???