A flat spot from sitting?

That reminds me of the old nylon cord tires they used to use on trucks. If it had been sitting for a while, you'd swear you had square tires for about the first 10 miles. Haven't seen any since the 70s.

 

I am no tire expert but that seems like a load of bull to me. Bias ply tires are known for flat spots but would go away once warmed up. Radials was the fix for flat spots. But even if it is possible to get a flat spot from long term sitting they should have went away the moment they heated up.

I would try dropping the pressure on all 4 to about 30 psi and drive it. It will give the tire a larger footprint and heat up the tire a little more. Curious to know if the vibration would go away. Let them cool and then air them back up.

 

19.5's could have flat spots, especially if they are low with air pressure. But the vibration should be gone fairly quick at highway speeds.

 

No, flat spots in modern tires from sitting for long periods is an actual thing, no BS. Tire Rack has a good article on it. Somewhat common in low profile and heavy duty tires.

 

redford, hope it is ok to share a link to tire rack's article. If not let me know and I'll remove but this is what I found when searching because I called BS at first as well.

Tire Tech Information - Flat-Spotted Tires (Due to Parking / Storage)

If the article on flat spots due to sitting.

 

It's OK. That is the article I was referencing. Thank you for linking it.

 

I had bad vibes on a newer Tacoma until I had the wheels balanced. They did the wheels first then mounted the tires, and balanced again. This fixed the vibes I had at 50+ mph.

Also had bad vibes on a sports car that I couldn't solve. All the tires shops said tires perfectly balanced. I finally let the Mercedes dealer "road force balance" them. Special machine that even the big tore shops around here don't all have. Fixed it and been perfect for 7 years since all the way up to 120mph.

 

I don't see how flat spots would not cause a vibration at ALL speeds. Doesn't sound right to me. I mean, the tire is not round. It's not going to pick a narrow band to cause vibrations.

 

Have the vibtraion on my F250 at 45-50 mph. None before or after.

 

UPDATE:

Drove the truck ~150 miles with 1200# of feed to see if the vibration seemed to change. It was still present while loaded even after the balance the dealership did when diagnosing the flat spots. There is vibration at all speeds and roads (concrete interstate, back road oil tops) although it is the worst right at 67 MPH and seems to smooth out some either faster or slower but the 60-70 range is terrible. Will be heading back to the dealership in a few days to see what they have to say or see if they can swap tires to just verify to is tires or something else.

 

Could be a bent wheel. Have them do a run out of just the wheel itself. Have them do the face then the outer edge to make sure that the wheel is true. Also check the rotors to make sure that they are balanced correctly. Have you ever tried to apply the brake while this vibration is happening. You may feel something in the brake peddle. If you do than it may be a bad rotor. Something isnt balanced right

 

UPDATE: Kudos to the dealership, got a call this afternoon checking to see if the issue had gotten better which I explained maybe slightly but nothing significant. They are going to speak to the service manager and see what next steps are. With just 350 miles now I asked if they would consider a rim/tire swap just to see if that was the issue. We'll see tomorrow. Really appreciate all the help guys!

 

Update: Not good news. Went to run to the store a few miles away and noticed a miss in the truck when I fired it up. Figured it was just cold or would straighten itself out. As I build speed the vibration was back and worse than ever and now the bad news, the check engine light popped on. The CEL (check engine light) started flashing and the AC stopped blowing cold air, then came on and stayed on. Immediately pulled over and called the dealership. They said to bring it in and on the drive over the truck felt like it had lost power. No knocks or clanks from the engine but definitely a rough idle and no power and bad vibration. The truck is back at the dealership and I'm back in a rental for a second time. This doesn't bode well for a truck with just 500 miles on it. I'm sick at my stomach right now and physically ill. Not sure if I'll ever be able to trust this truck.

 

Take a breath it will be ok. Maybe what you are experiencing is the motor. Hard for us on the web to really diagnose a problem with a truck but we give it our best shot. Ford will fix it and you should be happy when you get it back. With the number of trucks Ford produces there has to be some bad parts slip through. I do hope it's simple.

 

Thanks, and I know it will get taken care of but it's just so frustrating and I get that law of averages that things go wrong, it's just the why me syndrome. Thanks for the help guys and sorry if I came across in a bad light with anyone here. I really appreciate the help and guidance everyone has offered and couldn't be more thankful. This site is a real asset as is every member. It was just my rant and frustration coming though. Should know more in a few hours and will keep everyone posted. I'm thinking motor at this point but my experience with bad engine there has always been loud noises and smoke involved

Again, thank you everyone for all help and suggestions and even just asking as a sounding board for my frustrations and talking me off the ledge!