I believe I did 0.032 since that was on the low end of the range and my gap tool had that thickness. I think a consistent gap is more what smoothed it out than anything. I still have a slight vibration sometimes but nothing like the violent shake I had before. When it did it the other day I shifted to neutral and it didn't go away so I think what's left may be a balance issue.

Before I gapped the plugs I wouldn't even attempt going 75 because it shook so bad, now I can go 80 or 90 and not even realize it. Maybe I should screw up the gap again so I don't get speeding tickets.

The post about warm weather making it better seems to support my theory that it is an engine issue... But who knows. Mine has been good since, thats all I know.

 

I was wondering if it was missing too, but it did it on decel and in all gears, so I kinda doubt that it was an engine issue.

I took it for a long drive last night right at about 60mph the whole way and it was smooth as silk. Also averaged 20mpg the whole way

The truck was produced in December 2013 as a 2014 model, and it sat on a dealer lot for a year, so I can't help but wonder if the tires were flatspotted and needed warm weather to 'round out.'

My Mustang sat for a long time this winter and it took several long drives in warmer weather to get the flatspots out, so I suppose it's possible.

Just thought I would share my experience in getting this resolved, since no one else seems to have a fix.

 

So I also have this bad vibration on a 2012 f150 crew 4x4 off road Xlt. I'm on my third set of tires all have been road force balanced. New driveshaft, complete new rearend after bearings went out. More crap have been replaced then I can remember and the vibration continues. I believe the vibration is what took the rearend out. I'm pissed that I can't get this taken care of and am almost out of warranty. What has been the outcome with going to ford. Needless to saw this is my 7th or 8th ford truck and I believe it will be my last if I can't get this fixed. Pretty bad that my wife won't ride in it because it makes her nauseous. Any help appreciated.

 

Is there any fix to the issue? I just bought my first Ford a couple weeks ago 2010 XLT crew and noticed the vibrations yesterday. Have browsed threads but cant seem to find if there is an answer or fix to the issue. Truck has about 65k on it and the vibrations comes and goes at different speeds. Any help would be great.

 

Well after countless trips to the dealership over 18 months the truck was traded in on a new 17 f150 super crew. My truck had 2 driveshafts installed, rearend shimmed, new u joints, and more trips for what they hoped woukd fix it. I also tried 3 sets of tires at my expense and nothing worked. I talmed to ford and opened a claim and in the end they iffered me special pricing, but i actually gkt a better deal from the dealer. All in all Westlie motors did what ford recommended and tried some things on their own. Was I happy with the out come, no, but the 17 that replaced it is quite nice and wish I had gone eco right away. And the 10 speed is awesome.