Running falkin AT. I had them pumped up pretty high.
had vibrations growling and noise. Just getting louder as they age. Gonna rotate and balance.
At 75mph on throttle I get this vibration to up through gas pedal. Then I was thinking fan clutch or wheel bearings. Not sure but my truck is vibration and not feeling like it use to. I run Rancho 9000XL set at 1 all around for the wife.
Feel like I'm chasing a rabbit trying to find these vibrations.

Running 70psi all around.


Any suggestions

Scott

Happy New Year

 

Fan clutch or wb's unlikely to be throttle dependent. I'd look at u-joints and carrier bearing if applicable. *Maybe* motor mounts.....kinda unlikely but easy to check, just power brake while a helper watches FROM THE SIDE. Sometimes you can see top of motor over cowl from the driver's seat

 

Many, mostly longer wheelbase, trucks experience harmonic vibrations called frame beaming at certain speeds or RPMs that you'll never get rid of. You can sometimes do things to dampen it, or change the speed or RPM it happens, but it will always be there. 70PSI is way to high unloaded, your transmitting the bump of every little crack and pebble on the road into your chassis . You should probably be closer to 50PSI.

 

What size are the tires? If they are any wider or larger diameter than the stock, you can run lower PSI since the footprint is larger.

What year truck, how many miles? Does the vibration go away when you let off the gas pedal?

I'd get the tires balanced, run 55psi and see if anything changes.

 

275 70 18. Yes it goes away somewhat when I let off the gas.

 

275 70 18. Yes it goes away somewhat when I let off the gas.
tires have about 35000 miles

 

If you let off gas and it goes away even slightly, then it is most likely drivetrain related (u-joints, carrier bearing, slip joints, ring and pinion). 35,000 miles though seems pretty low for any of these to fail. Check tires first but you might need to inspect your u-joints or carrier bearing.

 

35k miles is low for a driveline component to fail...BUT I have personally had to replace the same u-joint in a rear driveshaft within 5000 miles (happened one time). I always pull my own driveshaft, take it to a shop and have them press the old out/new in...and I'm pretty sure whoever did the work on the first one didn't press things square, or possibly dropped it and let dirt in. So it's not unheard of - but definitely possible.

 

Just an FYI, I had Falken AT tires put on shortly after I bought my truck in '13. Consistently had a vibration ~45mph and then again ~70mph. I had them balanced by multiple shops including a truck service center, tire/wheel matched, road force balanced and never did get rid of the vibration until I had 4 Toyo AT's put on. I too did the driveline carrier bearing and u-joint replacement rabbit hole. The tires were my problem.

 

It would be great if you could swap tires and wheels with a buddy and see if the problem persists.

That could save a lot of trouble shooting time.

 

He said that the tires have 35,000 miles on them, not the truck.

 

Thanks all. This is all great info.
truck has about 40000 miles on it.
Gonna try balancing the tires first then the drive line.
Now do I have a hanger bearing I forgot. It's a short bed extended cab not four door. But will check the joints.
and good to know about the tires. This just started not too long ago as the tires are getting older.

Scott.

 

Delete!

 

2005 f350 drw, I had a rear caliper seizing up when it got hot...that was bad. I also had the death wobble from 30 to 40. Replaced front ball joints fixed that. Have you replaced the tierod ends or stabilizer, vibrations are hard on those