2nd Gen Non-Engine/Transmission Diff U-Joint Straps - Converted to U-Bolt

[Joe Mc]

Sorry no pictures.



Thought I'd share a little improvement I did over the weekend.



What led to the need - a few weekends ago I was givin the ol gal a few strokes of grease, when I came upon the rear u-joint I grabbed the shaft to shift my body a bit and I felt it move just a bit. Further examination revealed the cups were staying with the joint but the whole joint moved within the yoke? The straps had stretched. The memories of blown drive shafts in the old hot rod MoPars, that usually happened on the 1-2 shift, popped back in my mind. "Blasted darn MoPar couldn't use a u-bolt, had to come up with these stinking scrawny strap pieces of s_ _t"?!#@$%!



Anyway instead of just replacing the straps (why replace junk with junk?, right) I went to the parts house, explained to my buddy what I was trying to do and he pulled the correct strap to get the cup size and then looked for the corresponding ford (I know) u-bolt. BINGO!



You have to drill out the existing strap bolt holes on the yoke to the size of the u-bolt threaded ends, a bit bigger actually. Then a bit of finessing to widen the u-bolt is required to center on the two holes. Bing - that's it.



The kit (two u-bolts, lock washers and nuts) cost me $5. 50 and are made by Precision Universal Joint (made in USA), part number on the box is 330-10. Another smaller number on the box is 1099253-A.



If anyone is remotely interested in pictures let me know and I'll take a few snaps. To me this was no big bomb, just a piece of mind not having to worry about the shaft dropping out.

 

[LVJUNIOR]

I would like to see pictures if you get a chance

 

[SRath]

Just had my front driveshaft rebuilt and the guy said the old u-joint showed evidence of having met it's demise due to stretched straps. He showed me the shiny spots on the caps where it was moving in the straps.

Got home and checked the rear shaft. Sure enough, two less-than-finger-tight bolts (there's that 'clunk' I had been hearing) and another junk u-joint because of it.

I had been blaming the transmission shop that did my 5th gear nutjob for not torquing the scrawny little strap bolts and for not using Loctite on them, but maybe the straps just stretched. . ?

I see no advantage to straps over u-bolts at all except that they make it nearly impossible to overtighten and crush the u-joint caps, which could probably be done with u-bolts.

 

[E7mack96]

The advantage to the straps vs. the u-bolts is that it places a much more even load on the bearing caps.



You can bet that most places do not torque the bolts. Even where I work now, the old timers do not use torque wrenches for anything. I have already repaired 2 drivelines that the bolts were just finger tight in, causing the caps to spin in the yoke, ruining said yoke. These were repaired by them just days before.



If the caps are spinning, then there will be wear in the yokes mating area, which cannot be replaced even with new straps and u-joints. They may temporarily hold, but not with the original design strength.



I would give serious forethought before converting to u-bolts as a permanent fix. But as a temp - get me home kinda thing, go for it.



Just my thoughts...

 

[kentdiesel]

Please post some pics of your ubolt conversion.

Thanks,

Kent

 

[Joe Mc]

I'll get some pictures up this weekend, have to bring my camera home from the office tomorrow.

 

[rivercat]

Thanks Joe, good info!

 

[Joe Mc]

Here you go. Note the difference of the strap versus the u-bolt in the one picture where I'm holding the stock strap next to the installed u-bolt . . . The decision is yours . . . an easy and worthy upgrade for less than $10. 00 . . .

 

[CumminsPower98]

Just to be clear this is a Dana 70 correct? Haven't had any trouble with my 80 yet with 403k miles, lots of towing and about 300 RWHP. I did shave a few thousandths off the strap faces to make sure they would stay tight once and so far there has been no movement. Looks like a good upgrade for someone with a loose joint though.

 

[Joe Mc]

CumminsPower98 - you are correct this is a D70 (Autos only come w/70s), wish it was an 80 w/disc brakes . . . I had not experienced any problems up until I did the locker about a year ago, just noticed a intermittent "click" sometimes (letting off go pedal just as trans shifted, occasional when going R to D, D to R) about a few months ago. I think there probably wouldn't have been issue if the shop that checked my shaft for balance would have placed the straps back on correctly. Ticked me off that I paint marked "everything" to make the job easier on them and they totally installed backwards of the marks - almost as if on purpose! Last $ of mine they'll ever see!

Another thought we would think a stick trans places more "instant" shock on drive-line components (such as: ring and pinion gear, u-joints & straps), but clutch engagement is probably easier on these things versus the "clunk" of an auto from P to D, etc. So, who's to know for sure. I know the situation with mine at 180k and feel the u-bolt is the stronger option - MHO.

 

[odieub]

don"t the 70 and 80 use the same u-joint? so these same straps should work for both? and i made the comment over on compd in a thread about auto to stick conversion 70's only in autos 2500 and there is a guy that swears his dad has a factory auto bought new by them and has a 80??? i know dodge does some strange things.

 

[CumminsPower98]

All 3500 trucks stick or auto use the 80. Are you saying this guy is telling you his dad's is a 2500 auto with an 80? If so that's something I never heard of before either.



Sorry I can't answer the u-joint question.

 

[odieub]

yeap that is what i am saying 2500 with auto and 80



hear is the thread just rad through it transmission questions? - Competition Diesel. Com - Bringing The BEST Together