Ford Power Stroke Nation banner

U Joints N Axle wrap

4K views 10 replies 5 participants last post by  TRX370r 
#1 ·
Well I think Im killing my rear u-joint from all the axle wrap I have. I have a 6" Donahoe racing block and it can get pretty bad since I went up to the 37" tires. To give you an Idea how bad it is I noticed the other day that my overload spring is shiny where it has been rubbing the stop on the frame. I have not had anything in my truck for months or even towed anything so it shouldnt be touching. Just sitting static the overload is 3-4 inches from the frame mount.

Well yestrday I towed for the first time since I have had injectors and the new tunes ! :eek: Ohhh Boy the axle wrap is scary when your on the throttle with a load behind you. I think I can actually feel the back end of the truck lifting up and the more throttle I give it the more noise/vibration I get. Im gonna get some track bars soon but what brand of u-joints are guys having the best luck with? Back in my rock crawler days Dana Spicer seemed to always work the best what do you guys use?
 
#3 ·
holly hell tank that was horrible ha ha
 
#5 ·
Well I replaced the u-joint farthest back on the drive line and it still looked ok. I still have the vibration but I have narrowed it down a bit.

No matter what speed I go as long as its in the right rpm range with the converter locked it vibrates. 1700-2000 rpm over that and below that it goes away. I did the rpm test in OD and in 3rd and it vibrated in that rpm range when Im on the throttle, If I let off it goes away. so like 68-75 in OD and 50-57 in 3rd it vibrates and the more throttle u give it the worse it is. I think this is why I thought it was soo bad while towing because I was on the throttle hard in 3rd with OD locked out pulling hills.


To describe the vibration more : It feels like when you have a bad pinion angle or a ring gear going out on you. Maybe even like you forgot and left the hubs locked in. So its not super bad but its not normal and its slowly getting worse. Im thinking trans or transfercase but whats in there to cause that, center support? Any help would be good because at this point im not shure.
 
#8 ·
mine does the same exact thing,and when i let out of the skinny pedal i can feel the vibe go away.maybe when youre off the throttle,the axle is going back to its proper place and stopping the bad vibes??i dont know if traction bars will cure this. i thought they were mainly for controlling axle wrap on takeoff,but i gotta get a good set asap?have you gotten any pms about t bar recommendations?thanks
 
#9 ·
Just dealt with this issue... Its the ujoints if ya have a bad vibration. I blew the caps off the rear one a couple weeks ago at a pull, installed a new one, the vibe went away, then a week ago a new vibe came up suddenly.. replaces the center and the front ujoint (i have a two piece shaft)... well vibe didnt go away, just got worse.

Last night I was 8 miles from my house driving on a major hwy went to pass a guy (i was at 55 then moved over to the right lane at 60) my shaft exploded... or at least all three ujoints simultanesly exploded...
Made it home an hour later in front wheel drive...

The carnage was all 3 brand new ujoints... and all but one yoke on the driveshaft... so I scraped it an bought one taken off a recently scrapped truck of my same vintage, its in pretty good shape too.

Anyway my father who was a director for Freightliner in their R&D department, said in his 30+ years of failure analysis he'd never seen such a failure where the whole driveline had to be scraped.

The Cause... Napa Performance series ujoints #331 (Spicer 1350 series) made in china... Lesson learned... BUY SPICER lol
 
#11 ·
Im bringing this back up to the top. Im looking at changing the u-joints in the CV part of the driveline, has anyone does this? Maybe there is a write up on it some place and I just have not found it yet. I have changed alot of u-joints in my time but never a CV any hints on making it easy?
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top