My F250 6.4, 3.73 Crew Cab Short bed vibrates when accelerating from a stop with my 5th wheel on. The 5th wheel weighs 12K.
It is a medium to high frequency vibration that is felt throughout the entire truck. It continues through the shift into 2nd (TorqueShift Tranny).
The harder you accelerate the more you feel it.

It does not occur if truck is unloaded and you accelerate at full throttle.

Is this normal or should I get it looked at?

Thanks!

 

I had this happen to mine on the first camping trip we did. It is just a change in the driveline angle, try a helper spring or airbags and level it out just a bit. I pull a 8K TT not a 5th wheel. I was pulling a pretty steep hill from a stand still is when it happened.

 

I have never experienced this but I have heard that the torque converter will shutter. Could that be what it is?? Maybe a reprogram is in order.

First guess was also drivline angle change. But I heard of this other problem.

 

I believe there is a TSB about his issue. I had the same issue as you pulling about the same weight 5th wheel. They re-shimmed my drive shaft and the problem is gone. I have heard that re-shimming can also reproduce the the vibration when un-loaded tho.

 

TSB 08-24-06 will have your dealer checking the driveline angles and adjusting the axle and driveshaft carrier bearing. The TSB has been out for several months now.

Jay

 

I searched various ways through the TSB section, I cannot find this TSB.
Can anyone locate/post the details?
Thanks

 

Here you go jay. I don't believe we are allowed to post full tsb due to copywrite issues but here is the initial issue.

Some 2008-2009 F-Super Duty 250/350 vehicles with Single Rear Wheels (SRW) may exhibit an excessive drive-away shudder or vibration under moderate to heavy acceleration from a stop, especially when heavily loaded. This may be due to driveline angle. The shudder or vibration may be more evident while towing a trailer or if vehicle is over loaded.

Trailer tongue weight should be 10-20 percent of the total trailer weight, depending on the hitch.
If towing a 5th wheel trailer or gooseneck trailer the centerline of the hitch should be two (2) inches in front of the rear axle centerline.
Refer to the Owners Guide and Certification Label on the drivers door for maximum payload and cargo capacity.

Hope this helps.

 

I get the same thing when I tow my 5th wheel cargo trailer and it is loaded heavy. It only happens when I really get on the accelerator. If I go slow it does not happen, so, I go slow and ease into it.

It feels like the torque converter is complaining about the weight it is trying to pull so I just back off a bit. I would'nt say it's a problem, just a lot of weight to get moving and a lot of engine torque getting it moving. The two forces are putting a lot of strain on the driveline. Seems normal to me.

My biggest concern is slowing down. In tow/haul mode the trans. downshifts to engine brake. Sometimes when I have a heavy load the down shift is pretty violent. A loud bang, a big thud, my heart rate jumps, everything in the cab slides forward, drinks spill, etc... It's a PIA. My service tech. at the dealer says it's "normal" and the trans. is "bulletproof". I urged him to ride with me and he said "that thing is indestructible, don't worry about it" I told him I would call him when my trans. is all over the road 1000 miles away from home.

 

TSB 08246 was replaced with TSB 0949.
PDF link below.
https://www.google.com/url?sa=t&source=web&rct=j&url=http://www.powerstroke.org/forum/attachments/6-4-drivetrain-problems/11130d1257385850-weird-shutter-vibration-tsb-09.4.9.pdf&ved=0ahUKEwj1mIm7_YvWAhUKxYMKHVxRBFsQFg hBMAE&usg=AFQjCNFQ_c8ijOcnKR1EnaO5eI83tHPx_Q
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