OT - U-Joints on F-350

Embarrassing to a ask such an 'amateur' question, but here goes....

New to me 2002 F350 7.3 Crew Cab Dually, manual shift, dana 80 rear. This has a truck camper on it that will live there full time. Took it on a maiden voyage with the TC about two weeks ago. Had a slight vibration at between 60-66 MPH.

I dropped the rear shaft(s - its a two piece shaft) suspecting a bad ujoint. With them out, none felt particularly suspect, but the rubber bushing around the carrier bearing was a little wore out. Pretty sure that everything was original - lots of rust, etc, so I decided to PM the whole thing - new u-joints and carrier bearing. I pressed out the old joints, which, again were pretty rusty, and started assembling the new ones. I'm not a u-joint expert, but I've done a few (10-12?) in my time. I replaced the original spicer joints with Moog 330's.

Bottom line: I've got them all in, sorta. Most were/are tight. I pressed them in and tried not to 'over press' them, but they basically needed to be squeezed all the way to get the snap rings in. They all move, but nowhere nearly as freely as the old one (to be expected). They are definitely tight enough that they will 'wear' in if I leave them.

One, on the bolted yoke that mates to the transfer case, would not accept the snap ring, but its mating face was not flat, and I was hoping that once installed and pulled down tight, it would 'open' the yoke enough to accept the last snap ring. I haven't tried it yet, but it was at least 10 mil from accepting the snap ring on the workbench. No - there are no pins that have fallen into the cap - its not that far off and I can tell that the caps are seated correctly against the cross.

So looking online, there are lots of folks that seem to have this issue with this particular (spicer) driveline and u-joint. Many ending up grinding the caps slightly. I could pull the one cap and turn it down 10 mil. Also, in digging around, I learned that Moog also has a 330a ujoint that is 10 mil smaller (by using thinner snap rings)- apparently there's a genuine issue with the correct length on GM and Dodge trucks (google Moog 330 vs 330a). Even replacement spicer joints come with an 'array' of different snap ring thicknesses.

so...

- Run it and let them 'wear in'
- Pull them and turn down the cap?
- Buy another joint and put in the thinner clips?

I know we have some driveline experts on here (Reed). Thoughts? I need this thing to be bulletproof.

Here's the Moog 330 vs 330a bulletin...

https://www.moogparts.com/pdf/did-you-know/english/DYK14-107U-ENG.pdf

Did you 'Press" the u-joints or 'Drive' them. FWIW I never use a press, for reasons best left in the scrap pile. The Moog PDF may apply, I live next to Ford KTP (where most Ford F250 and larger are born) and there has always been a Dana driveshaft plant down the street.

Had a similar issue with front knuckle joints on my 07 dodge. The Moog were a poor fit, and the snap ring grooves not machined at the correct position on the cup. I went with genuine Spicer joints and the assembly was painless. I know it's not the application but that's my experience. FWIW, there are some different grades of Spicer available, for some part #s. Some not serviceable, and some that come with a grease fitting.

Pressed. Started them in a vice by hand until they were sliding in smoothly and while manipulating the u-joint cross, then finished pushing them in with a small/cheap hydraulic h-frame. Also tapped one cap in the final bit. So I guess a mix of both. But no wailing with a hammer and drift.

badwithusernames said:

Had a similar issue with front knuckle joints on my 07 dodge. The Moog were a poor fit, and the snap ring grooves not machined at the correct position on the cup. I went with genuine Spicer joints and the assembly was painless. I know it's not the application but that's my experience. FWIW, there are some different grades of Spicer available, for some part #s. Some not serviceable, and some that come with a grease fitting.

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At first I was gonna get the spicer parts. Upon disassembly, I decided to go with the Moog. Reason being that the spicer part had a thick boss around the 'center' of the cross section that made disassembling the joint impossible with out destroying it (i.e., the boss contacted the yoke before the cup was pushed out).

Searching online indicated that general solution was to just cut the u-joint out by cutting each of the crosses. If I run these Moog parts burn up within the next next ten years, I'll go with the spicer just to have the different thickness snap rings.

Whack the side of the ujoing yoke with a hammer and they loosen up, you do this after the clips are all in. That probably makes no sense in written word, in practice it works perfect.

kustomizingkid said:

Whack the side of the ujoing yoke with a hammer and they loosen up, you do this after the clips are all in. That probably makes no sense in written word, in practice it works perfect.

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Yup, that was the way I was taught at a garage, never got the u-joint any where near the press.

Clean your bores out with a flap wheel on a die grinder too.

Smacking the "wrist area" makes the arm bend out ward a wee bit (probably that .004 your chasing with different clips)

You swing the joint to check for tightness, smack it and you'll feel it loosen right up.

kustomizingkid said:

Whack the side of the ujoing yoke with a hammer and they loosen up, you do this after the clips are all in. That probably makes no sense in written word, in practice it works perfect.

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Have done this on the middle joint that is fully assembled. Didn't really loosen things up. Will do on the others now that the shaft is installed.

digger doug said:

You swing the joint to check for tightness, smack it and you'll feel it loosen right up.

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That seats the cups outward against the clips after they are in.

Personally I'd surface grind the clips to the "Improved" thickness. If you don't have a surface grinder turning the cups would be OK if you can get it all apart without destroying them.

Yeah - I would start by whacking with hammer as has been said. If that doesn't do the trick - I have used a nut and a bolt to force the joint far enough apart to get the snap rings in - simple, cheap, and works every time.

Do you still have the OE clips? How thick are they?

Joe Miranda said:

Yeah - I would start by whacking with hammer as has been said. If that doesn't do the trick - I have used a nut and a bolt to force the joint far enough apart to get the snap rings in - simple, cheap, and works every time.

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Joe - you mean that you take out the joint and slightly spread the yoke jaws, then re-assemble?

Mud said:

Do you still have the OE clips? How thick are they?

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Eyeballed, they are the same as what came with the new joint. 0.020 I think..

I would need to make a video to actually show what you do... its one of those tricks that is really hard to explain, but once you see it makes total sense.

If you can get the joint apart OK, check the length of the cross and the thickness of the bottom of the cups, see if it all adds up correctly and matches the OE joint.

kustomizingkid said:

Whack the side of the ujoing yoke with a hammer and they loosen up, you do this after the clips are all in. That probably makes no sense in written word, in practice it works perfect.

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This.

When the joint is properly assembled, the yoke will fall down by its own weight. If it sticks out like wedding tackle its to tight. A little rust in the bore can also cause this problem.

I do hope you made some reference marks when taking it apart. I have witnessed many vibrating shafts that were not assembled in the same line as original. I hate the small vibrations so much I had it balanced and what a difference it made.

Antarctica said:

Joe - you mean that you take out the joint and slightly spread the yoke jaws, then re-assemble?

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Yes. I did the same thing as Joe suggested on a u joint for a PTO shaft. I used a short length of all-thread and two nuts/washers, and was able to spread the yoke just enough that it assembled without being tight. It took a lot of force even to spread it just a few thou, but it was a relatively large u joint that had heavy forged yokes.

https://www.youtube.com/watch?v=uewFHe6H2Tw

If I remember correctly, Eric O demonstrates the "whack" method in this video. (BTW, one of the very best mechanic / automotive troubleshooter on youtube, has a way of teaching you without "teaching you" if you know what I mean.)