Normally stack height is determined by which collar you have. There's like 5 options and having the right one makes all the difference. Sometimes people stack a wasker or too under the pivot to help. The pivot threads need to be sealed though. They are exposed to fluid on the backside.

On to the next area of frustration. I ordered a joint (Dana 5-1501X) off RockAuto for the prop shaft. When it appeared that wasn't going to arrive anytime soon, I ordered a pair of 430-10 based on the posts in the other threads. Neither version is the correct size for the prop shaft on my '75.

My joints are 2.575" from outside of cap to outside of cap, and have .947" OD bearing caps.

The Spicer 5-1051X is 2.525" outside, and has .985" caps (same as replacement listed on ZcarDepot) Caps are TOO big, joint is undersized

The TUS-10 (430-10) is 2.34" outside, and has .875" OD caps - WAY too small all around.

Removing the factory joint - some ppl mentioned a stake ring that can be removed - there is no such thing on mine. I ground the stake area out, and removed the UJoint using the same process as for a standard external snap ring style

remove the caps holding the yoke to the shaft

then remove the caps holding the joint to the yoke 

Yoke to shaft orientation is marked

inner land where the lock ring will presumably sit

ID of yoke - approx .955" - no way a .985" cap is going in that

Datsun cap to cap (measured at 2.575" / 65.5mm?)when holding the caliper, have to recheck that #

Datsun cross end to end approx 2.405 / 61mm

Cap OD approx .947" / 24mm

cross shaft OD  approx .702" / 18mm

TUS-10

5-1051X

 

Edited July 8, 2024Jul 8 by HusseinHolland

15 minutes ago, Patcon said:

Normally stack height is determined by which collar you have. There's like 5 options and having the right one makes all the difference. Sometimes people stack a wasker or too under the pivot to help. The pivot threads need to be sealed though. They are exposed to fluid on the backside.

Dang. That would explain it then. I just used the collar that came with the trans, as the new one I ordered came as the (obviously) incorrect part. I didn't catch any alternate dimension collars when I was looking on RockAuto, not that that is a surprise.

Spoke to Jason at the UJointStore (where I had ordered the TUS-10's) - based on my measurements, my prop shaft takes the TUS-11a - .947" cap OD, 1.65" yoke land spacing

 

They should put the specs on their web page.  Looks like it's only made to match the Honda Ridgeline from 2006 - 2008, but the page might be incomplete, there might be others.

Odd that your 75 is either unique in u-joint size or the other folks that have tried the staked joint repair have a different (wrong?) size in theirs.  The back flange is unique so maybe everything is a one-off.

https://ujointstores.com/product/tus-11a/

Edited July 8, 2024Jul 8 by Zed Head

8 hours ago, Zed Head said:

They should put the specs on their web page.  Looks like it's only made to match the Honda Ridgeline from 2006 - 2008, but the page might be incomplete, there might be others.

Odd that your 75 is either unique in u-joint size or the other folks that have tried the staked joint repair have a different (wrong?) size in theirs.  The back flange is unique so maybe everything is a one-off.

https://ujointstores.com/product/tus-11a/

When I spoke with him, he said that joint is very low volume sales, not sure he would change the listing details. It not even in his sizing chart.

I re-read one of the posts on HybridZ, and Oblithian, with a '75 2+2 had the same size Ujoint requirement (except he measured span @ 1.647", but still). He ordered 430-11a

Edited July 8, 2024Jul 8 by HusseinHolland

I read the Subaru drive shaft uni-joints were the best replacement for the 280Z and came with inner circlips.

Rockford u-joint replacement kit 430-10 "Staked in" replacement. 

I can't confirm fitment.

The thread has morphed in to a "1975 has a unique u-joint" topic, in part.  It has a different bolt pattern at the diff flange and it appears that it uses a different size u-joint.  The 430-10 doesn't work for a 1975 propeller shaft, at least this particular one.

He started discussing it in Post #71.   Lots of stuff in between.

 

Installed the correct U Joint (TUS-11a) today, and then reinstalled the prop shaft, heat shield, exhaust, starter, fan clutch & throttle linkage at the firewall. Also added an OEM 5 speed shift knob. Driving it around a little - it definitely feels nicer than the 4, and doesn't make the horrendous noises of my worn out 4 speed. 3rd is a little whiny below 4K rpm though. No idea how many miles were on the trans.

Installed the joint in the yoke first. Started with one cup pressed  in enough that the circlip could be installed, with the cross set in so the needle bearings don't walk, then set & pressed the second cup in just enough that the circlip fit in the groove

Then I did the same with the prop shaft, set one cup in deep enough to set the circlip, then did the same for the last cup. Normally I'd just tap the cups in the way I remove them, but since the initial opening of the yoke has a step in it from the staking, that doesn't work very well ( I tried that first). After the joint was fully installed I just tap each yoke in the open vice jaws to relax the yokes after pressing, that makes sure the cups aren't tight or binding in the yokes. It felt perfect.

Prop shaft back in

Heat shield on

exhaust on

Trans filled - only took 2 quarts (started dripping at the end of the 2nd quart. I was surprised, as I thought these took more than 2 quarts to fill

Fan clutch back on ( I had removed it as it was mentioned the engine dropping at the rear could cause interference). 

 

 

Edited July 13, 2024Jul 13 by HusseinHolland

On 7/13/2024 at 4:21 PM, HusseinHolland said:

Started with one cup pressed  in enough that the circlip could be installed, with the cross set in so the needle bearings don't walk, then set & pressed the second cup in just enough that the circlip fit in the groove

Did you measure the play (axial displacement)?  Just wondering.  Not much to be done if it's off but it would be interesting to know.  These instructions are hard to understand but they can be guessed.

6 hours ago, Zed Head said:

Did you measure the play (axial displacement)?  Just wondering.  Not much to be done if it's off but it would be interesting to know.  These instructions are hard to understand but they can be guessed

 

I didn't measure anything. I treated the end float in the same manner as standard joints that have the cup clip external to the yoke. Once it's all assembled, I find that typically the joint will more often be 'tight' from squeezing or loading either yoke. I set each yoke in open vice jaws so that the opposing yoke is resting on the vice jaws & tap (with a dead blow hammer) the base of the yoke (where it's welded to the shaft or sleeve). This forces the top cup outward a hair. Rotate & repeat for each cup. Hard to describe, but it works. You can easily feel by rotating the end yoke whether there is any end float or binding in each axis. 

I didn't photograph that stage - the prop shaft would be set similar to this pic I took to illustrate disassembly 

 

Edited July 15, 2024Jul 15 by HusseinHolland

I understand how it went together.  I was asking for any future searchers wondering if this will give good results or not.  Can't tell.  If there's too much play you'll probably get vibration.  If it's off-center, the same.  It's a good quick "get by for a while" repair though.  Might be fine for a long time.  It's just much less precise than the Nissan procedure described in the FSM.