9" yoke removal and replacement

[jknight16]

Hey guys, hopefully this one should be a slam dunk for you. I recently had a 9" rear built for my 69 Camaro and (due to my lack of explicit directions) the builder re-used the large round yolk that came with the rear-end (It's out of a Versailles) rather than what we would typically use for a car application.

After nearly 4 months of waiting for the thing, I just wanted to get the rear-end from him so that I could keep this project moving, but now I think it would be in my best interest to change out this yolk. Will removing the nut and yolk change all of the tolerances and setup of the center section or is this somewhat of a "bolt-on" affair. I'm going to have a new driveshaft built for this car anyway, so worst case I could have one built for this large round yolk, but I doubt that's the way to go. Your input is much appreciated guys!

[OHCbird]

It depends- Did he use a solid spacer or a crush sleeve to set the pinion preload? If solid, you should be good to go.

[jknight16]

So that's the determining factor eh? Well, I'm not sure there's anyway of knowing that until you're already into the process, so maybe I'll just have to give it a shot and see!

Chalk this one up to another live and learn point of muscle car building :banghead:

Oh yeah, Go Blue!!

[GUS68]

In all actuallity, as long as you use common sence it will be fine. I have worked as a mechanic at a shop for about 10 years, and when a car or pickup comes in with a leaking pinion seal, you use an impact to remove the nut then remove the yolk remove and replace the seal then install the yolk then tighten the nut with an impact, usually till the nut quits turning and then a rattle or two and call it good. I know this sounds crude but when time is money and you don't get carried away with the impact it will be just fine. And we have never had a comback because of the pinion nut too tight or too lose. But if you are really concerned about it, I would use some paint or peen a mark on the nut and the end of the pinion so that when you tighten the nut after installing the new yolk, you will know when to stop in the same place and that will be plenty close. :twothumbs

[GUS68]

Also, before you go to reinstall the nut give it a wack or two on the side of the nut that faces out, the nut is a locking nut and when new is distorted on the outer side to act as the locking part (makes it go on hard) but after a few times of removing and installing the threads become "good" again (like a normal old nut) and the locking part is gone, just lay the nut, yolk side down on the cement floor and give it a good smack with a good sized hammer, this will distort the threads again and you will not have to worry about it comming loose.

[OHCbird]

Impacting a nut on a crush sleeve setup can throw off the crush collars width, which will throw off you pinion preload. That being said- it does take 200ftlbs to set most to the correct rolling load, which would negate the effects of some impacts. However- some are noted to hit 275-300ftlbs peak. I've seen a few get dorked up.

On a wheeze-bag 200hp production car, using the impact might not be felt for a long time, and might not affect it. Put 400-500+hp to the wheels, and you're asking for problems. Either way- I wouldn't risk it when it's just as easy to do itright (drop the pumpkin out & do it on a bench).

[GUS68]

Yes. the correct way is to remove every thing and do it all over on a bench. BUT have you ever crushed a crush sleave??? You need a large tool to hold the yolk and then a 3/4" breaker bar with a pipe on it and then you start to pee your pants while you pull on that bar. Real world, Zap it with an impact! Like I have said, we have replaced countless pinion seals at work this way, and not just me, the 4 other guys there, on cars pickups and one ton duellys, and to my knowlege never had a come back because of over tightening with an impact!!!!! And I would think that a one ton truck that pulls a goose neck full of lumber day in and day out for the local lumber yard would put alot more wear and tear and stress on the rear end than you summer day hot rod. Zap it!

[Madspeed]

Yes. the correct way is to remove every thing and do it all over on a bench. BUT have you ever crushed a crush sleave??? You need a large tool to hold the yolk and then a 3/4" breaker bar with a pipe on it and then you start to pee your pants while you pull on that bar. Real world, Zap it with an impact! Like I have said, we have replaced countless pinion seals at work this way, and not just me, the 4 other guys there, on cars pickups and one ton duellys, and to my knowlege never had a come back because of over tightening with an impact!!!!! And I would think that a one ton truck that pulls a goose neck full of lumber day in and day out for the local lumber yard would put alot more wear and tear and stress on the rear end than you summer day hot rod. Zap it!

Im afraid Hes right here.

I have done the same thing for years But I have a feel for how thight things are.
Ive allways set pinnion preload by feel w my hand as well never had a comeback. Funny thing is I just recently bought a tourq wrench to actullay se it =)
In all Honesty it just takes the right person to do it this way. dont ask me how but i can just feel when a bolt is within its stretch limits.
Ive allso since childhood been able to see size differences in very minute amounts such as the difference between a 10mm or 3/8 in a huge pile or 14 vs 9/16

[jknight16]

Great, thanks for the input guys, very much appreciated. While I can't say that I share MadSpeed's ability to function as a human torque wrench or micrometer, I would like to think I'm sensitive enough to the mechanical limitations of the materials to prevent any serious thread failures.

So, I suppose my plan should be to acquire a new yolk (any recommendations or warnings?) maybe even a new pinion nut (so as to regain its self-locking ability) and hope that the pinion seal comes out without damage so that it can be reinstalled? The diff has never had fluid in it, wonder if that will affect anything with the removal of the seal...?

Basically, I'm a dope when it comes to differentials and anything rear-end related (hence my inability to prevent him from reusing this silly yolk in the first place), but I'm relatively adept otherwise so i'm trying to gain a sense of what I'll need to get this done without too much cursing.

Bravo gents, and thanks again for the guidance.

[big gear head]

There are about 6 different yokes (not yolk) for the 9 inch Ford. There is a 1310, 1330 and 1350 for the car and truck. The car yoke is longer than the truck yoke, and then there are the companion flanges, which is what you have. There are at least 2 of these. You need to know which one you need before you try to change it. I would guess that you need a car 1310 yoke for your original drive shaft to fit.

When you install the yoke there is no need to remove the seal if it is not damaged or leaking. You will need to put some red Loctite on the threads when you install the nut even if you use a new nut (experience talking) and smear some RTV sealant into the splines of the yoke when you put it back on. Oil will seap out through the splines if you don't. Be sure to lube the seal too. Use a torque wrench and torque the nut to about 150 foot pounds. This is enough to keep it tight, but not crush the spacer and change the bearing preload. The standard 9 inch Ford pinion housing uses a crush spacer and the Daytona pinion housing uses a solid spacer. I doubt that you have the Daytona pinion housing in a Lincoln rear end, so you will have the crush spacer.