hmbjohn

I haven't heard any good results from the shim kits by Ford (not saying they won't help) but I have heard and now KNOW that the Roadmaster Active Suspension kit does reduce the axel wrap (takeoff shudder) by about 95%. This kit is easy to install (takes an hour) and will raise the backend about one inch.

I love it and made my 157" WB ecoboost feel strong again.

Robbie Sapp

So my question is, would it be better to install the roadmasters on the rear of the axle or on the front? It would seem to reduce axle wrap they would need to be placed on the front, keeping the front of the springs from flattening -elongation- and then flexing upward. One would think the added tension from the RAS on the front would keep the spring from doing such whereas on the back it seems as if it only causes the back to arch more allowing the front to flatten.

F-250,LD

I had this issue since new. I have the same truck as the OP, except for the engine.
I also have a topper.
The dealer felt that the driveline angles were off so they added a shim under the transmission (~3/16"). This minimized it. Next they replaced the stock trans mount with a Raptor mount (I'm not sure if the shim is still in there). The shutter is pretty much gone. I did have it again when towing. Since then I have added a leaf to the rear spring packs. I used the 998# spring and removed the factory block http://www.generalspringkc.com/Add_a...012_s/1995.htm
The ride height is back to stock. I haul weight a lot so this minimizes the squat. It also minimizes squat when towing. I rarely feel the shutter now. These leafs reach almost to the factory leaf eyes so I'm sure they help with axle wrap.

With that said, I'm not sure if the issue is bad driveline alignment or axle wrap.

RajunKajun59

Look where the contact point on the front of the RAS kit is. It counter acts the tendency for the block to roll out. Thus stopping the spring from flattening

Willicuddy

I have this same issue with my truck and so does my old man on his truck.

Vibration from take off that goes away after about 20mph or so. This issue is almost eliminated if I accelerate very softly (not as much tension on the drivetrain I would assume).

Mine is a 2010 FX2 5.4 with 6.5ft box (2-peice shaft) Only Felt Towing or load in bed

His is 2013 FX2 5.0 with 5.5ft box (2-peice shaft) Only Felt Towing or load in bed

Also my previous truck 2002 Harley Davidson F150 2wd (2-peice shaft) Mostly felt going up hill under acceleration, I never towed with this truck.

Clearly this is a 2-peice drive shaft issue. There is too much torque for the long shaft and the weakest link are the rear springs thus the resulting axle wrap.

I spent hours and hours at custom drive shaft shops trying to fix it on my old 2002 truck. Nothing worked, it was still there shimmed the carrier and shimmed the springs... nothing. The only thing I never tried was installing new, heavier duty leaf springs.

Would something like this

http://www.generalspringkc.com/product_p/43-1783hd.htm

eliminate the problem as it is a better more permanent solution over the roadmaster option.

Just throwing the idea out there.

Ronnie Wallace

2010 one piece drive shaft.
Bought it 4 months ago. I noticed the clunk on test drive, dealer fixed it. Not sure what they did, but he said it was common problem with the drive shaft.

Also, I've had a slight shudder on take off. I changed the rear differential fluid & shudder is gone.

jagsfan

My 2005 Lariat Supercrew had this symptom. I paid $15 for a bottle of friction additive.....Cleared it right up.

jagsfan

I then put the friction additive in the diff, Sorry...Should have said....

Willicuddy

The shudder would happen on when you were towing or had a load in the bed?

tomasulo

Cleared mine up too, last Fall....and no issues since.....👍🏽