Thoas Lindemann

Seeking your thoughts, I have a 2013 5.0 Super Cab that I lowered with a 3 front 5.5 rear Belltech kit. I have a hard time cutting up a 2013 truck so I willing elected not to move the carrier bearing by cutting the stock pads off the crossmember. The result is the truck has a slight shudder on low speed exceleration, I can live with it as the rest is smooth and I have a little more than 15,000 miles on it this way.


The truck has developed a vibration at 80 mph decelerating in 5th and 6th (cant replicate it in 4th). I pulled the driveshaft out of it and u joints feel good. The tailshaft flange has some play in it and Im assuming this is where its coming from. I took it to ford of course they dont want to do anything because its been modified and are saying because its lowered it caused the problems and im **** out of luck.


Im racking my brain trying to figure out how lowering it can effect it, the only thing that is possible is that the slip joint on the drive shaft is bottoming out and shoving the whole driveshaft forward and this is what destroyed the rear bushing (at least this is what the dealer is telling me) but as the truck squats in the rear the driveshaft pulls itself a part, so I dont really buy this theory (but Im trying to look at every concievable angle) Other than that I dont see how lowering it can do anything and think its just their way of getting money out of a customer.


I have a request in to Fords hotline to see if they will do anything for the trans but not holding my breath and preparing to pay a local trans shop to go through it. Im also gonna put a one piece driveshaft in it and do away with the carrier bearing, and go through pinion angle if needed (but this I was planning to do anyway not that i see the 2 piece as a problem)


Anyway just curious of others thoughts on this any angles appreciated.

maxpat82

vibration on a high speed rotating mass like a drive shaft can make some damage.

Lowering the rear change the joint angle and create vibration.
Sometimes just adjusting the pinion angle can solve the virbation issue, but on a 2 piece drive shaft, most of the times the carrier bearing need to be relocate to adjust the front portion of the driveshaft angle and then the pinion can be readjust to be vibration free.

I did it in my 07 and it a easy job. Putting the carriere at the stock place later on is only a matter a lengthening the bracket or making sleeve/busing(or redneck style with a big stack of washer and stock bolt) to move the carrier at the stock position. really easy to do.

Thoas Lindemann

what is the proper way to set driveline angle with a two piece driveshaft? Ive found tons of info for a one piece but cant really find something giving a descriptive idea on a two piecer.

maxpat82

every other piece need to have the same angle.
In a 2 piece drive shaft:
transmission and rear drive shaft piece should be the same.
front drive shaft piece and diff should be the same.

Thoas Lindemann

After doing extensive research this is what I’ve seen inregards to a two piece driveshaft. First drive shaft should be treated as an extension of the transmission output. Since the first drive shaft doesn’t have a corresponding u-joint to counter you must run it with a very low working angle(i.e. .5 degrees) the second drive shaft both the universal at the slip jointand at the rear end should have a working angle between .5 and 3 degrees and since the universal at the slip joint is cancelled by the universal at the rearend, they must be within 1 degree of each other.

After taking time and fully mapping the driveline angle I can see how me lowering it and not moving the carrier bearing upwards has created some angles not conducive to a proper driveline. What surprised me was that the working angle of the first universal exceeded the limits that Ford prescribed, mine has a working angle of 4 degrees (and this was unaltered from Ford). Reading that the Raptor transmission mount cures some vehicles driveline shudder, I would suspect that it may be a little taller and actually corrects the driveline angle.

I’m going to raise the carrier this weekend, then remeasure driveline angles and correct as needed, I’m fully confident that I can correct and in fact make better than what Ford initially set up.