Rough Ride on Smooth Road

[PaleRider555]

Just bought a 2011 F250 Lariat 6.7 Diesel Fully Loaded has FX4 Package and 75R18E Continental contitrac TR Tires. This thing feels like I am driving down a bumpy road even when I am on a newly paved Highway. 1700 miles on the truck. Today I put 500 lbs. in the bed and went down the interstate, back end fells fine but rough ride still there and seems to be different at different speeds. I then went to the Tire Dealer and asked them to road force balance the tires. I asked them to check them all first for a before and after. They put the them on thier road force balancing machine and said all of the tires were perfect and no need to change anything, only the driver side front was out .5 of an ounce. They were at 60psi before I pulled in and I had them put them all at 65psi.

After further test driving it seems the roughness is speed related and is worse between 40mph and 45mph in any gear. I was doing 40 in 6 then i dropped it to 5 then 4 and it stayed constant rough ride. I even had a friend drive it and he said the same thing, worse at 45mph

I drove at speed down one of the bumpiest roads around and the truck handled great.

This rough ride thing is killing me. I will take it back to the dealer tomorrow but I am afraid they will try to downplay it.

Could it be a slipped belt? or out of balance drive shaft? or tranny issue? Any ideas would be appreciated. Thank You.

[tjbrowder]

Me thinks your drive shaft is out of balance.

Take it to the Ford house.

[PaleRider555]

Took it to the Dealer today and the service manager drove it for a long drive. Unfortunately there are not a lot of smooth roads by this dealer. We did find a good little stretch where he agreed the truck did seem to ride rough even though the road was smooth. We then took out another truck from the lot and he said that he still felt a little rough ride on the smooth road but mine was more prevelant. He offered to put the tires from the other truck onto mine and drive it to see how that feels. We will do this in a couple days.

I then took this thing for a 40 mile highway drive and I hated it. Was not comfortable and I could feel this "out of round / balance" feeling the whole trip. I am sick to my stomach about this truck.

I don't think it is tires. I believe it is something like tjbrowder thinks. Maybe the output shaft of the transmission has a bad bearing? I will keep you posted.

[matty21]

mine had bad shocks right from the lot. get them looked at . worth a try

[champ198]

There is a similar thread on another PSD board. I hate to point you to another board outside of this one, but there's been a lot of discussion.

Rear end bounces @ 40-45 MPH - Ford Truck Enthusiasts Forums

[PaleRider555]

Took it back to the dealer Friday of last week. They put some Michelin Tires from a truck on the lot onto my truck. I drove it to work and have put about 100 miles on it with these tires. No difference. As a matter of fact, I think it is getting worse. It seems after it is warmed up it will shake/wobble/bind at 28mph to 32mph then again 40 - 45. seems to smooth out at 52 - 55. It is an "out of round", bad bearing, out of balance sensation with an occasional binding like a u-joint that is stiff / doesn't want to turn. The truck will actually move me side to side in my seat slightly as if I just went over a speed bump. Weird! I will be dropping it off at the dealer for him to take it home and see for himself. I have also called ford customer service and supposedly a customer area rep will be getting ahold of me in 2 days. The guy on the phone mentioned a buy back. I don't really want a buy back rather a fix or a different truck that actually rides correctly. I don't even want to drive this thing as I think It might be doing damage to the truck. Stay tuned or chime in with feedback.

[derekwitt]

I feel your pain Palerider. I have the exact same thing on my new dually. I can save you a lot of trial and error. I have done the following,
- first balanced the driveshaft
-second changed to a different set of tires(same brand)
-third put different tires/brand on all together
-fourth, put on expensive aftermarket shocks
-fifth, had Ford put on new "heavy duty" driveshaft
-drove three other duallys which all had simular ride effects

Guess what, she is what she is and its a pissoff. I believe it is a design issue with these new trucks and nothing will change that annoying harmonic hop. If you find something else that helps other than what I tried, please let us know. But hopefully this will help eliminate some things. Good luck and sorry.

[ShortlineCline]

I would recommend adding drive shaft geometry (angles) to the list of things that need to be checked. These two piece drive shafts tend to be finicky as they have an extra cardan joint so there is three angles that need sum out.

Had this same problem on a Dodge and the dealer was no help. Finally ended up buying an inclinometer and some angled shims for the rear spring perch and fixed it myself.

[Lead Foot]

Nothing worse than a Bad riding truck!

I had to get rid of a 09 2500 LTZ GMC Extra Cab,due to "Frame Beaming" Even after the rear Hydraulic cab mount fix which fixed about 60% of it i still wasn't happy and Finally got Rid of the truck!

Funny thing is the 07 same truck only a Chevy rode freaking awesome ? Go Figure...should have kept that one :~(

Extra cabs and Crew cabs have this issue due to being so Long... Not all truck show it... just a lucky hand full LOL

[Hotrodgibs]

shoulda bought a F150 for ride quality......it is a heavy duty truck ya know. not exactly built for cruising around.