ECOsleeper

Own a 12 f150 ecoboost truck runs super great, super fast.
Problem is after 80 mph begin to have a small vibration and not sure 🤔 how to rule out the problem. So far I've put new tires and had alignment done ✅ and still same vibration after 80 any help thanks.

RLXXI

Highest legal speed limit in the U.S. is 75mph, slow it down.
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ECOsleeper

Thanks for the input but FYI I'm a cop 👮🏽 nobody does the speed limit it's out of respect to follow the speeding law and 5 over the speeding limit is passable.

Eric Kleven

What's your gear ratio? 80mph is probably starting to spin the driveshaft into a resonance mode...

650NutKase

80+ is fast for a truck...being in LE as well, not a good example to set. But I digress. Rotate the tires and see if the vibration stays the same or gets worse. Could be a balance issue or an air pressure issue.

PerryB

That's my suspicion. You might go to a driveline shop and get a little better balance job that lets you get through that particular harmonic region.

BCMIF150

I'm so glad that being a cop makes you think its right.

ECOsleeper

3.55 is my gear ratio. I haven't tried rotating my tires but will do so and re try the tire pressure. Getting to 80 mph i get very fast 💨 with my set up. I know it's just a truck but how many trucks do u know out there pushing more then 500 to the tire breaking into the 12s.

Meathead

iTrader: (2)

Apparently you have never been to Texas. There are highways with limits of 80 here.

RubberShield

lmfao , i can get my truck to go well over 100 mph and no vibration . Anyway check your bearings , seals as well