Ford F-150 drive shaft vibration


#1

I have a 2007 Ford F150 crew cab. It has a 5.4 litre engine, towing package rated for 10,000 lbs and a 6ft bed with a two-piece drive shaft. I pull a 26ft travel trailer, DGW 5938 lbs, GVWR 10,000 lbs, and approx actual weight 7000 lbs. At approx 10-15 mph there is a vibration from (according to Ford)the drive shaft. Ford said that the trailer(not too heavy) pulled the rear end too far down and that’s what caused the vibration. The put two “shim’s” in drive shaft to “stiffen” it up, but that did not solve the problem. Do you have any suggestions about what could correct this situation?

Thank you in advance


#2

I don’t know where you could put shims in a driveshaft, thats a new one on me. A vibration could be due to an out of balance driveshaft, bent driveshaft, bad center bearing or bad U-joint.


#3

Maybe they put shims at the center bearing support. But that sounds ridiculous. You might have to live with this problem.


#4

I’m also curious about these shims. The first thing I thought of was shimming a center carrier bearing but this would be counter productive since this would have a tendency to straighten the driveshaft out. Drivelines require a certain amount of angle in them to operate smoothly.

The second thing that occurred to me after revisiting your post is if the yoke on the rear differential has a flat plate with 4 bolt holes. The rear U-joint is also attached to a flat plate that mates against the plate on the yoke.
Surely these guys are not spacing those 2 plates apart with flat washers or something?

If so (horrors) avoid these guys and get someone who knows what they’re doing and have them take a look at this. If they are spacing those 2 plates apart with flat washers this means the shear strength of those 4 small bolts is seriously compromised and it would not surprise me one bit to see a driveshaft being chunked loose sometime; especially pulling a trailer that heavy.

You may have to consider something like airbags on the rear to keep the tail end of the truck up.
Hope some of that helps and good luck.
(Definitely get that rear yoke looked at promptly and see if this is what they did)