My 242 SYE solution/write up. (56k beware)

So there has been lots of discusion about a 242 HD SYE. Just so everyone is on the same page. There is no heavy duty slip yoke eliminator conversion for the 242. 231 TCs have various HD SYEs from Advanced Adapters, PORC, and others that replace the stock output shaft with a bigger stronger one. My solution is not a HD output shaft SYE.

I looked at Tom Woods. A lot of money for a glorified hack n tap. Although I'm sure it's a good job, I didn't want to take the time and money to do this. There is the RE hack n tap. I have heard of loosening, and then wobbling. (from Tom Woods) There is another company that cuts and taps the shaft, but then heat treats the shaft. $$$ The only option at the present time is a hack n tap.

I was steered to this site http://www.driveshaftsuperstore.com/drive_shaft_SYE.htm
After talking to them, decided to give it a try. A RE HnT can be found for $80, so for $20 more, why not? I wanted it for these reasons
1. You can bolt a front drive shaft directly to it.
2. I machined it to fit tight on shaft (more later)
3. Stronger than a RE HnT
4. No adapter or anything else needed

This is what I started with.



As you can see it is plenty long. I cut it to the length I needed. Wanted 1 inch of spline contact. There is space at the yoke end with no splines. About .25". So I had to leave 1.25 of splines on the output shaft. Next I did this.



You can see by the cut off piece that the yoke shaft is splined the entire length. The diameter of the splined part on the output shaft is 1.172". after the necked down part, the shoulder at the TC seal is 1.178". I had a friend machine the inside to fit tightly on the shoulder all the way to the seal. This is what gives the strength. More shaft engagement (still just 1" of spline contact) to eliminate wobbeling. You can see my cut and tapped shaft here



The shoulder part is .7" so plenty of contact. From there, the yoke slips right on and it's bolted like any other HnT.



From there, I just bolted up a front shaft from an 4.0 auto. I wanted a good shaft, so I went to a parts yard and paid $70 for a 99. Later on, there was a 98 in my u-pull yard. Late models are real rare in my u-pull yard. I got the front shaft for $15. So for the $99 yoke, and $85 for shafts, I now have a SYE, a 99 front shaft on my rear, and a 98 shaft for a spare. I'm real happy with the results. I had a friend machine it, but it isn't complicated. If I had to take it to a machine shop, it couldn't cost that much, $20-$25 bucks??? Feel free to pipe up if you have any idea. There you go. What do you think???

How fortunate to see this. I just posted a question about this very idea earlier today http://www.naxja.org/forum/showthread.php?t=80242. Thanks for making me not think it was crazy and undoable.

I dont get it,Oscar already sells the yoke "pre-machined",why all the extra work?

Who's Oscar? If it's the guy from Phoenix, I though I read on here in the last year or so that his work is somewhat shoddy.

Thats who "DriveshaftSuperstore" is!I bought my 1st H-N-T from him 5yrs ago,replaced it 4yrs 11months ago with a JB HD kit no problems since.

Way to think outside the box.

And I thought mine was a non-shortshaft SYE!
Your's is the short shaft eliminator kit!

I am doing the same but my parts have been sitting on a boat for over a month already! As I have a 95 242 I have the added problem of still having to seal the back of the speedo housing. I have a yoke from a Corvette.

RCP Phx said:

I dont get it,Oscar already sells the yoke "pre-machined",why all the extra work?

Click to expand...

Good question. The outside of the spline on the output shaft is 1.172". The inside diameter of the yoke is 1" or a little less, can't quite remember. (the root of the splines inside the yoke shaft are 1.178") The top of the splines inside the yoke. The splines will not fit over the 1.178" of the shoulder by the seal.

So, you could get the yoke, cut it down to 1.25" of shaft (allows for 1" of spline contact), screw it on and you are done. But that is why some don't like a RE HnT. If it loosens, it wobbles on the end of the shaft, which changes the splines on the output shaft. Loosens them up.

Mind you, I am not bagging on RE HnTs. They solve a problem. Thousands are out there, many with no problems. If they do loosen though, things get messed up. So I machined out the splines at the end of the yoke. The yoke is fit tightly on the shaft. I have 3" of shaft contact, .7" of shoulder contact. If it does loosen up, it is not going to "flap around" on the end of the shaft. I wanted the yoke so I could bolt up a front shaft. The 6" of shaft it comes with is just a bonus. Why cut it all off. I just tried to make use of it and strengthen things the best I could. If you ask me, I think it's briliant!!!

Here is where it was spoken about 3 months ago and gives you some other yoke options.
http://www.naxja.org/forum/showthread.php?t=75385

Ya, and by the way, thanks guys. I talked with Go Jeep and John90xj a few times about this and they helped me out o lot. rocks!!!

Here, take a look at what I did a while back.

http://www.naxja.org/forum/showthread.php?t=38907

It might give others some ideas if they're searching.

Okie Terry said:

Here, take a look at what I did a while back.

http://www.naxja.org/forum/showthread.php?t=38907

It might give others some ideas if they're searching.

Click to expand...

That's cool. Consolidate info. So you are the one that did that. I had seen that before doing some searching. I think earlier you were comenting on how long it is. It isn't any longer that any other. Well, except that I have 1.25 of spline left. It does look long though. I actualy thought it would be shorter than a RE because I wasn't using a adapter, but that probably isn't true. The center of first joint is probably the same length as a RE after everything is said and done. It is as short as it can be. No really, I'm not defensive.

Just a quick question, did you see how your mate machined the yoke out for you? Just wondering how to hold that yoke end in the lathe jaws while working the other end removing part of the spline? If I had another yoke I could bolt them together and do it that way but cant think of any other way?

Gojeep said:

Just a quick question, did you see how your mate machined the yoke out for you? Just wondering how to hold that yoke end in the lathe jaws while working the other end removing part of the spline? If I had another yoke I could bolt them together and do it that way but cant think of any other way?

Click to expand...

If that question was directed toward me,
I just put the yoke in the lathe.
Nothing special.
The bar was long enough to reach all the way through the yoke to turn off the splines.

CRASH said:

Isn't the generally accepted rule of spline engagement 1.5 times the minor diameter of the splined shaft? I assume you guys are giving up some strength to do this mod?

Click to expand...

It's the only thing that hasn't' broken on my rig, yet.
And that really amazes me.
I really didn't think it would have lasted as long as it has, under the abuse it sees.

Not sure if any of this is to me. My friend that machined it used a vertical mill. We have a nice new lathe at work, but it had a 3 jaw chuck on it. Our 4 jaw would work but it needed the hoist to change it and that wasn't setup yet. (it's a new lathe) So we used a vertical mill with a special head. It was a pain though becase we really had to do a lot of setup/measuring to make sure it was truly vertical and centered.

As far as spline engagement for me, I had no idea there was a rule of thumb. I just went by what RE HnT did. Don't know if it is right, but lot's of people use them with no spline issues. I thought it was a little short and was more comfortable with 1.25" of contact.

Thankyou for your replies.

I realize this writeup is for a 242, but would this work on a 231 TC. Could I cut the yoke to a length that almost touches the output shaft seal and have the splines machined out of the end? Also, since i'm kind of a noob to this sort of thing I was wondering about u-joint compatibility betwen the yoke Dirt Surfer used and the DC on a front DS. Is the difference in u-joints in the size of the body, bearing cap, or both?

Thanks in advance,

Ron

The unis are 1310 series which are the same size used both on the front and rear driveshafts. The same thing has been done by John who confirmed to me it was possible as he had done on his 231 some time ago so you will have no problem doing it on one.

This is an update. I was discusing this on another thread and decided to update this.
Tom Woods. Honestly, I believe it to be more trouble than what it is worth. Again, there is no "heavy duty" output shaft for a 242. Hack and taps are the only thing that can be done. To break down your case to replace your shaft with one some one else cut and tapped is more than I wanted to do. I spoke with TW and decided not to go that route.
Let's make this clear. I HAVE A 96 AND NEWER 242. It's a 2000. Come to find out, things have changed. On older 242s, TW just cuts the original splines off and taps a hole. On the newer 242s it is a different story. TW cuts the shaft back to the bearing, they respline the shaft to 26 spline, and use a CV yoke. The yoke butts up against the bearing. There is more than an inch of spline contact. Then they machine out the tail housing to accept a different seal. The $400 core charge is for the output shaft AND the tail housing.
When I decided to do what I did, this was not an option. However now, for late model 242s, I believe this is a much better option. A drive shaft is going to run $300-$350. So for $150-$200 you get a short output shaft, with a CV yoke, new seal and a stronger unit. I am actually thinking of doing this.
I have been happy with my setup. I have had vibes. There have been a lot of factors. Finally got my angles right w/ adjustable LCAs and shims in back. That helped. Belived it to be speed related. Had both DSs balanced. They said my DS joints were shot. Replaced/rebuilt CVs and U-joints. It helped. Believed my D44 yoke to be unbalanced. It was. Replaced, it helped, but did not solve my vibes. The only thing left is my rear output yoke. Can't believe it to be out of balance. Only get vibes after 60mph. They do not go away and they get worse. TW said that with my CV joint being so far out, that at speed my output shaft could be flexing.
I haven't confirmed that, but it seems reasonable. It is the only thing left. I can't sit here and say what a great thing this is and you should do it too when it MIGHT be the cause of my vibes. My yoke is no further out than any other hack-n-tap. I have a inch of original splines left. It would be the same for older 242s as well, TWs included. But for newer ones, the option of a shorter output shaft would be much better. If the shaft breaks, it is on the inside of the bearing. While this is not a "HD" shaft, a shorter "lever" would make for a stronger unit.
Also, I don't want a new rear shaft. Mine is rebuilt, and I carry a spare front shaft that I can use for front or rear. If I went the TW's route my rear DS would be too short. I am bummed that TWs will not just sell the SYE w/o the DS, but if I got the SYE then I need a new DS!
So here I sit. I really want to solve my vibe issue (besides not going over 60 mph, ha ha). I don't NEED any of this stuff, and really don't like the idea of changing it AGAIN. However, if I had a newer 96+ 242, and I was trying to decide which way to go for a SYE and DS, I would have to say that TWs SYE/DS package looks very attractive. Hope this helps.