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in the old days the top pin was a round bolt head of the spring pack bolt. bottom pin was a round nub cast into the block. not sure if theyre still configured that way but it looks like the bottom pin is sheared. i wouldnt pull any heavy weights until you get it fixed as the shear forces will now be transfered to the ubolts and theyre only meant to supply a vertical clamp load to the assembly
OP - You had me intrigued about the U-bolt being bent so I took a picture of my truck to compare. The U-bolts look the same as well as the exposed yellow marker paint on the leaf spring. The one differential I see is your lift block has shifted/looks out of square.
OP - You had me intrigued about the U-bolt being bent so I took a picture of my truck to compare. The U-bolts look the same as well as the exposed yellow marker paint on the leaf spring. The one differential I see is your lift block has shifted/looks out of square.
(Ignore the red oval I drew....)
thanks for the picture! I sent the pic of mine to a ford mechanic I know and he told me there's no way that block would shift without other obvious damage, but I can't find any damage anywhere.
thanks for the picture! I sent the pic of mine to a ford mechanic I know and he told me there's no way that block would shift without other obvious damage, but I can't find any damage anywhere.
It is going to have to be disassembled to see the damage. Sheared centerbolt in the leaf spring is my guess. I have seen it before.
thanks for the picture! I sent the pic of mine to a ford mechanic I know and he told me there's no way that block would shift without other obvious damage, but I can't find any damage anywhere.
Huh. Isn't that what I typed at the beginning of this thread?
Completely dumb idea to take anything apart without at least getting a 4 wheel alignment check.
Huh. Isn't that what I typed at the beginning of this thread?
Completely dumb idea to take anything apart without at least getting a 4 wheel alignment check.
never said I took anything apart. Not sure what you're flustered about. Im camping hours from home without a full tool set so no need to worry about me disassembling anything.
In my opinion, the axle hasn't shifted but the block has pivoted on the pins a bit and has made contact with the u-bolt. I'm going to take a guess that the shear weight of the 35' fifth wheel and making an abrupt stop caused the bump stop to slam against the riser block tang causing the block to twist. The axle actually moves at an angle, not straight up and down so the bump stop would strike the block at an angle. Maybe take a rubber mallet and coax the block back into position.
Then again, it could have come from the factory this way. There's nothing to keep the block from pivoting. The overload is prevented from pivoting by a large spring pin in that second hole which pins it to the other leafs.
ya the block may have just rotated. with just one photo from the rear its hard to say. if the front of the block is offset on the perch toward the inside ( oposite the rear) then likely it just rotated. if the entire block is offset to the outside ( like in the photo) then for sure it sheared atleast the bottom pin
So I have a 2019 f-450...doesn’t seem to matter what you have ....
With the suspension at curb height, tighten the U-bolt nuts evenly in a cross-type pattern in 4 stages.
Stage 1: Tighten to 65 Nm (48 lb-ft).
Stage 2: Tighten to 130 Nm (96 lb-ft).
Stage 3: Tighten to 200 Nm (148 lb-ft).
Stage 4: Tighten to 265 Nm (195 lb-ft).
but I seem to remember 400 ft lb being the final torque on my 2010 f-450
So I have a 2019 f-450...doesn’t seem to matter what you have ....
With the suspension at curb height, tighten the U-bolt nuts evenly in a cross-type pattern in 4 stages.
Stage 1: Tighten to 65 Nm (48 lb-ft).
Stage 2: Tighten to 130 Nm (96 lb-ft).
Stage 3: Tighten to 200 Nm (148 lb-ft).
Stage 4: Tighten to 265 Nm (195 lb-ft).
but I seem to remember 400 ft lb being the final torque on my 2010 f-450
any comment
My 2017 OEM Service Manual states:
Tighten the new U-bolt nuts in a cross pattern in 4 stages.
never said I took anything apart. Not sure what you're flustered about. Im camping hours from home without a full tool set so no need to worry about me disassembling anything.
"I'll get a better look when I'm back home after Christmas, and I can take it all apart." -Rictator, 2020 December
People here don't understand that U bolts are a one time use item on these modern trucks. They are torque to yield.
I think deductive reasoning is in short supply these days. Besides the obvious visual checks of the stack shifting, which would be plainly visible by clean paint lines, a 4 wheel alignment would clearly expose an improper thrust angle. I am completely dumbfounded why some on here don't recognize that.
You don't go tearing anything apart based on a 'hunch', unless, I guess, you like wasting money and time.
Also, I'm not flustered, it just reads that way. 🤣
"I'll get a better look when I'm back home after Christmas, and I can take it all apart." -Rictator, 2020 December
People here don't understand that U bolts are a one time use item on these modern trucks. They are torque to yield.
I think deductive reasoning is in short supply these days. Besides the obvious visual checks of the stack shifting, which would be plainly visible by clean paint lines, a 4 wheel alignment would clearly expose an improper thrust angle. I am completely dumbfounded why some on here don't recognize that.
You don't go tearing anything apart based on a 'hunch', unless, I guess, you like wasting money and time.
Also, I'm not flustered, it just reads that way. 🤣
_______________________________
You have quoted this a few times:
People here don't understand that U bolts are a one time use item on these modern trucks. They are torque to yield.
People here don't understand that U bolts are a one time use item on these modern trucks. They are torque to yield.
Where are you getting this information?
Hobo
"U-bolts are a torque to yield bolt. This means when you tighten down a U-bolt to its proper torque spec, the bolt stretches to achieve that level of tightness. While the U-bolt has some flexibility in its ability to stretch after being loosened, the bolt will never tighten enough to allow it to regain its full torque spec potential." -Beattie Spring
"We recommend that the u-bolts be replaced once they have been torqued to spec." -Eaton-Detroit Spring
Additionally, when Ford replaced my rear axle, the u-bolts were replaced as well. The service advisor at the dealer showed me the shop manual that explicitly states u-bolts were not to be re-used. If this was not a big deal, penny pinching Ford would not have sent four brand new bolts with the new axle.
These bolts have the responsibility of handling power delivery to the rear wheels of a truck that develops over 450 HP and 1000 ft lbs of torque at the crank. There is a reason why Ford and experts in the suspension industry want them replaced anytime they are loosened, whether that be from bolt elongation, or thread deformation.
