pinion nut question

[flatlander]

I managed to swap the 308 rear for the 373, but ran into a minor problem. The yoke on the '75 dana 60 is smaller than the yoke from the 84 dana 61. I thought I figured it out by comparing a u joint from both trucks and measuring them both, but the 75 ujoint ended up being a tad too long. Maybe I can keep shopping, but I'd rather just put the yoke from the old rear end on the new one and use my existing u joint.

Now the question. Can I just take off the pinion nut and pull the yoke off or is there some interesting consequences I need to be aware of?

 

[MIDNIGHT RIDER]

The big nut comes off, then maybe a washer, then the yoke should slide out.

Be careful of any pre-load washers that may be behind the yoke; keep them where they are.

Replace the pinion seal.

Slide on the other yoke; maybe it will fit; probably it won't and all of this will have been for nothing.


The correct thing is to replace the big nut with new; I never have; what I do is buggar the outside couple of threads and tighten the whizz out of it.

 

[RLDSL]

If switching the yokes doesn't work, Find a real good driveline shop, you should be able to get an adapter U joint, it'l be one size for the driveshaft and the other size for the yoke. You will have to measure carefully first to determine what U joint the yoke is supposed to take.

 

[Russ]

I've done the two sized u joints before. Take both of the old ones with you.

 

[Mr_Roboto]

How much too long is the U Joint?

If the diameters of the cups are the same, you can grind a little off the ends of the cups, and grind a little off the ends of the cross without harming the strength or function of the joint.

 

[typ4]

zthose year dana 60 yokes should interchange with no trouble. The preload shims are under the bearing so no worries there.

 

[f-two-fiddy]

Also, it's recommended to replace the pinion nut whenever you remove it. After reading the posts of self loose pinion nuts, I can see why it's recommended.

 

[sle2115]

When I sold parts, if I had both u-joints, I could 99% fix you up with a u-joint that would work. If you want to go that route. I would say avoid your mass merchandising and stores and go straight to a quality parts store, probably napa, something like that. I ran a Parts Plus and a Auto Value, but I'm just saying that around here, if you go into Advance or Auto Zone with anything that isn't listed in their computer, you're out of luck.

And yes, you can remove the pinion nut with no consequences, but make sure you get it tight and I would probably dimple a thread or two, or get a new nut. IIRC, the torque spec is like 200 ft./lbs. or something like that. Don't hold me to that number, I'm just saying it's substantial!

 

[f-two-fiddy]

I agree, the torque is 'substantial' prolly part of the reasoning for a new nut?

Part of the reason I'm farming out my R&P swap is because I don't have anything that will accurately torque that nut. A new wrench would cost the same as the shop charges for the swap.

 

[lotzagoodstuff]

Any good driveline shop will set you up with the correct flip-flop ujoint, IMHO it's easier than swapping the pinion. I would buy two of them so you have one for reference so you can show any parts guy you ever have to deal with exactly what you are looking for.

 

[MIDNIGHT RIDER]

YES, you can get some hybrid U-joints and make weird things work.

I hesitate to do so.

Some day you will be in some little quaint mud-lick town, such as the one I live in, and you are gonna need a U-joint; good luck .


First, I would see if the yoke swap will work; that is the cheapest/easiest.

If that don't do it, I would get the drive-shaft yoke that fits the U-joint that fits the rear and have it welded onto the shaft.

I have done this a number of times; you just need to remember that that one U-joint is for a different application.

I have a Chevy truck with a Dodge rear-end and U-joint; and, I have a Ford truck with a Dodge transmission and U-joint.

Any of my U-joints are in stock in any little old parts-house; not so with those hybrids.




The reason that they recommend the big nut be replaced is on account of a factory-new nut has the outside threads sort of folded together in four equidistant spots around the perimeter, thus making it a "locking nut"; as already mentioned, you can accomplish the same thing by dimpling those threads yourself.


I wouldn't worry about a specific torque value; I just get after them with a cheater-bar on a 3/4 or inch breaker-bar; the only one I ever had back off was installed at the factory.

 

[typ4]

The dana rears dont have a crush sleeve ,they tighten up the yoke /bearing package with shims behind the front bearing, a new nut is not near as important on these.

On the other hand the ford diff has a damn crush sleeve and the torque of our geartrain tends to loosen the yoke and splines ,hence the "need" for a new nut with more breakaway grip.

 

[flatlander]

Ok here's what I did. I measured the yoke on the 75 rear end. Ended up need a 1.063 dia cup with a 3.22 length. The drive shaft yoke was 1.063 X something. I can't remember. I took the original u joint in which was equal length but 1.125 on the diff and 1.063 on the drive shaft. We then started looking through the book at napa and found one that was just right. It is part number 457. I put the end of the box into my 3" thick file folder just in case. I also bought an extra.

Installation is another matter. I couldn't press the cups into the drive shaft yoke and managed to bend the ears on my driveshaft. Not a ton, but enough that I can't get the snap ring on on one side. See my "wanted" post. Strange because the joint I bought from Advance auto parts fit the drive shaft nicely, it was just too long for the diff yoke. So I calmly pulled the cups off the advance joint and put them on the napa joint and voila! They fit. Seems the advance cups were tapered where the rubber grommet goes on, the napa ones weren't and were catching on the snap ring groove.

Now I have a mobile truck but no brakes. I'll work on the brake lines tomorrow night.

 

[RLDSL]

YES, you can get some hybrid U-joints and make weird things work.

I hesitate to do so.

That's just one of those things where you carry a spare, they aren't that expensive. Worse come to worse, if you have the part number, they are a standard item and even the mc parts places can get you one the next day so long as you hand them the part number. you just can't expect them to be able to look one up.

I'm going to have to do that on mine here shortly when I get my auxilliary tranny installed

 

[jimmys f250]

had problem the other day,,,loose pinion nut,,didnt have new one jus put some red loktite on it, should stay I'd think