Good vibrations or bad 60+mph harmonics
#1
Good vibrations or bad 60+mph harmonics
Hi all,
New member of the forum and new owner of a 2013 FX4 F-150 Supercrew 145" 3.55 gears Ecoboost 1000Km. Unfortunately I am one of the unlucky when it comes to highway speed vibration. Good news is the dealer is doing their best a trying to solve the problem.
Reading another forum (can't remember which one) I read about a technique to determine the harmonics at which your vehicle is vibrating. It involves downloading an application called "vibration" onto your Iphone or Ipad. Placing it on a surface in your vehicle (I used center console) and taking a sample. I did this to try and be a little more informed when taking it to the dealer. Although I never mentioned anything about doing it to them. They actually have their own vibration analyzer that probably does a way better job (MTS 4000?). Anyway attached is one of the samples I took.
I believe the culprit is the frequency the vertical cursor is on at 765 rpm or 12Hz. The other large spike on the right in the Y axis is at 2703 rpm or 45Hz. Now what is rotating at 765 rpm at highway speed? I have 20" scorpions, they rotate 652 rev/mile or 652rpm at 60mph. Doing one of those solve for x equations (60mph x 765rpm)/652rpm = 70.3mph was my speed or 112kph. As for the other spike at 2703 rpm, 2703rpm/3.55gears = 761 rpm. Close enough to the tire rpm so that spike seems to be the drive shaft. So I thought awesome it's the tires and drive shaft. I was wrong.
Dealer confirmed vibration:
balanced tires - still vibrated
rotated tires - still vibrated
swap out known good drive shaft and tires - still vibrated
further diagnosis required.
Am I screwed? Is it expected these trucks vibrate this much? Definitely not comfortable for a long road trip like this. Well at least that vibration application is pretty cool for showing me how my truck is vibrating.
New member of the forum and new owner of a 2013 FX4 F-150 Supercrew 145" 3.55 gears Ecoboost 1000Km. Unfortunately I am one of the unlucky when it comes to highway speed vibration. Good news is the dealer is doing their best a trying to solve the problem.
Reading another forum (can't remember which one) I read about a technique to determine the harmonics at which your vehicle is vibrating. It involves downloading an application called "vibration" onto your Iphone or Ipad. Placing it on a surface in your vehicle (I used center console) and taking a sample. I did this to try and be a little more informed when taking it to the dealer. Although I never mentioned anything about doing it to them. They actually have their own vibration analyzer that probably does a way better job (MTS 4000?). Anyway attached is one of the samples I took.
I believe the culprit is the frequency the vertical cursor is on at 765 rpm or 12Hz. The other large spike on the right in the Y axis is at 2703 rpm or 45Hz. Now what is rotating at 765 rpm at highway speed? I have 20" scorpions, they rotate 652 rev/mile or 652rpm at 60mph. Doing one of those solve for x equations (60mph x 765rpm)/652rpm = 70.3mph was my speed or 112kph. As for the other spike at 2703 rpm, 2703rpm/3.55gears = 761 rpm. Close enough to the tire rpm so that spike seems to be the drive shaft. So I thought awesome it's the tires and drive shaft. I was wrong.
Dealer confirmed vibration:
balanced tires - still vibrated
rotated tires - still vibrated
swap out known good drive shaft and tires - still vibrated
further diagnosis required.
Am I screwed? Is it expected these trucks vibrate this much? Definitely not comfortable for a long road trip like this. Well at least that vibration application is pretty cool for showing me how my truck is vibrating.
#3
Mine seems to have a vibe issue above 70 and I had tires balanced etc. It is a minor nuisance to me but it shouldn't be there. Oh and my truck is going in today for warped rotors (20K miles) and an alignment check because the inside edges of my front tires are wearing out........nice.
#5
Ford Customer Service
I'm glad to see that your dealer is working hard to get this diagnosed. Let me know if you need any help in the future!
Ashley
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gullable300 (09-04-2013)
#6
yes, were all screwed, my feeling is it is the terrible rims/tires. I got Chrome clad wheels and 20inch rims with the POS Pirellis. I am giving these tires 20k and then swapping out for MS2's. I believe it will help reduce the vibration. I also believe it is in the drivetrain/shaft. I sit in my truck at highway speeds and watch my pass seat shake and vibrate and my cup of coffee ripple like theres a breeze. To me there are sooooooooo many little annoyances with this F150,,I don't think we should be ragging so much on the competition. I still prefer the Ford truck but they better bring there best foot forward on the next Gen F150 and SD if they expect me to be a 3 peat truck buyer..
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#9
Senior Member
I had a vib at 70mph which I solved by adjusting my toe-in a small amount inward (1/8 turn of each tie-rod). I have stock pirelli's on a 4x4 which I believe use a larger toe spec than 4x2 trucks. I plan to get a real alignment when I replace my tires with Michelins. My situation could be different than yours. I felt mine in the steering wheel as a small shake at exactly 70mph. I also noticed the amplitude varied with road surface type (worse on brushed concrete) which is why I played with the toe. I'm completely good now and I don't really care if the wear on the pirelli's is a bit higher.
#10
OP update - no solution yet
Truck is back in for service.
-TSB 13-08-10 applied - still vibrated.
-Dealer is in contact with ford engineers. Engineers suggested trying tires from known good vehicle, still vibrated.
-Passenger rear axle seems to have a little wobble, they replaced - still vibrated.
Another call to the engineers and further diagnosis required.
So far impressed with the dealers persistence.
-TSB 13-08-10 applied - still vibrated.
-Dealer is in contact with ford engineers. Engineers suggested trying tires from known good vehicle, still vibrated.
-Passenger rear axle seems to have a little wobble, they replaced - still vibrated.
Another call to the engineers and further diagnosis required.
So far impressed with the dealers persistence.