By the way, before going to the dealer to get a diag, I went to the my corner garage to get the wheels rebalanced. Tires were way out of balance but the vibration was still there.

 

I don't think my truck has that. It's a SuperCab 6.5 ft bed, so 145" wheelbase.

I have new snow tires on my other wheels that I could throw on for testing purposes, but it's a lot of work to rule out something that I don't think is the cause. If it stayed the same when I shifted to neutral or got on the throttle, maybe, but it seems like it has to be driveline related given the symptoms.

 

I agree with you. However, I also have a set of snow wheels that I change myself every season. This lead to the wheels to never be rebalanced after several years of usage. Not a bad idea to get them rebalanced anyway after 2 or 3 years. The weights were off by a good 4 in after rebalance.

 

Dealer wants to spend more time with the truck. They were able to reliably duplicate the vibration but not pinpoint the cause.

 

Got word back from the dealer. They believe it's a bearing in the rear differential, so they are replacing rear differential bearings. They are also replacing a u-joint.

 

Carrier and pinion bearings were replaced along with the rear u-joint and it's ~70% better. What's left doesn't go away in neutral so I think it might just be tire balance.

Dealer says all bearings were discolored from heat and he found no preload on the pinion (it would freewheel when spun by hand). They also said the u-joint was binding on one axis.

 

My guess, you might still have a drivetrain alignment issue.

 

Wouldn't that be an odd thing to have happen on a truck that's stock height? I found the service procedure to measure it, so I'll pick up a meter at some point to see if it's off.

Truthfully, between this and the rest of the history on this truck I'm inclined to stop chasing issues and just run it through the winter then trade it. It kills me because I can't get anything quite like it anymore, but it's just been too many issues and I'm getting tired of chasing one thing after another on a vehicle that's been meticulously maintained. My last F-150 was so solid, I don't get what happened with this one.

 

'Odd' is a relative term nowadays. Are you original owner? Some leased vehicles are run / towed pretty hard. I have similar truck as you, no vibrations to speak of. I get your frustrations, I'm afraid other brands have their issues as well. My advise, if you feel Dealer as best they can be, tires well balanced, maybe let another shop go for a ride with you. Good luck.

 

Yup, owned since new. Truck's been through both a front and rear differential rebuild, two camera replacements, APIM replacement, cooled seat blower replacement, new thermostat because it was starting to run hot, transmission reflash to address shifting issues, a bad speaker, I don't even remember all the little things. The kicker is 90% of the time, it's used for commuting on 45-50 MPH rural highways. I tow maybe 3-5 times per year, and only around 6000 lbs. Haul some house project stuff from time to time, but it isn't heavy - just things like plywood, a water heater, or an exterior door. It definitely doesn't live a hard life.

My last F-150 was solid - this one has just been a lot. I think the thing that compounds it is my local dealer's service department is absolutely terrible, so I travel over an hour to a different dealer that is actually competent - then I end up with a Fusion or Escape for a few days while they deal with the latest thing. Even with all the stuff this truck has needed, I'd be willing to try another F-150 but they no longer make the option combination I want. I had a Tacoma in the past and considered going for a Tundra. I hear the new ones have their share of issues, but at least there's a good local dealer that's excellent to work with.