TH400/D18 clearance problems, HELP!!

[porkchop]

Well I finally got my tranny and my new D18 in today. After getting all the bolts in and the mount on I was laying under the wag just looking around and noticed that the front output looked a little close to the tranny. I went and got the front shaft and sure enough it won't fit! It hits the tranny!. I do have part of the original shaft that was connected to the t-case when I got it and that seemed to work fine. Here are some pics:

http://www.fortunecity.com/silverstone/fuel/62/id53.htm

http://www.fortunecity.com/silverstone/fuel/62/id56.htm

What are the chances that a double slip shaft can be made, and will it work? Or can the CV shaft be turned around so the CV connects to the axle? I have been without 4wd for so long and was looking forward to getting it. Going back to a D20 is no option!!

Thanks guys.

[scotty]

pc,i fear there is no wat to make the cv joint work with the auto. how much lift do you have? can you use a standard driveshaft,with a simple u jopint on ech end? since you now have part time,you no longer have to worry bout the d shaft spinning while in 2wd.put a regular d shagt in there,jack it up to full droop on the front end,and spin it and see if it binds. maybe your solution is as simple as using a shaft with no cv.

i apologize for not seeing that prollem earlier in your planning stages and forewarning you. it is not surpising that you have clerance issues with an auto,specially a big one like a th400. i had to clearance the shift tower very slightly for clearnace on my t18,but the front shaft has plenty of room- i didnt even think about it. my suspension is stock,so a standard u joint drivesahft works just fine for me.

how is your rear angle?is it working out as well as you hoped? with my 3" blocks reinstalled,mine is a very slight downward angle. at stock height is was darn near parallel to the framerail.

why would you want a double slip shaft?i think it would work-sorta. the one with least resistance would max out first,then if you actually had that much travel,the 2nd would pull out.

hope this helps.

[porkchop]

Scotty, there is no reason to apoligize. There is no way you could have seen this coming, and niether did I. I was thinking of a double slip joint because I have three drive shafts in my garage and I am trying to figure a way to make this work. I can make one shaft out of two. I have to use the slip part of the original shaft in order to have a double slip shaft. It looks like I will be researching more.

The rear shaft seems ok but I won't have it hooked up until tomorrow to tell for sure. I will let you know. Thanks for all your help up.

[Erix Jeep]

Hmmm, double slip shaft.... My mind started whirling onthis one PC and I had a sudden thought. (Notice all the smoke?) If you wanted a double slip shaft, hardest part would be which end does the middle slip to? In other words a three piece shaft?

My thought was, that might be a decent idea, and if you try it, I would suggest a spring inside the shaft, at each end, to center the sliding part of the shaft. Might even get a lot more travel out of a shorter shaft that way. Just my .02 worth. [img]smile.gif[/img]

[porkchop]

I have decided to give the front shaft a try. I think the spring thing might work out great!

I have other problems too. The rear shaft is now to short . I am going to go to a junk yard and see what I can find before I bring it in to have it lengthened.

[Stuka]

That sucks PC. I knew the front output on a D18 was alot closer to the center then a D20...but didnt think it was that much.

About your 3 piece shaft idea....not sure how strong that will be....its worth a try if you dont mind spending the money to do it. Some sort of spring would be a must to keep the center piece in the center..and ot drooping down. lets us know how it turns out.

[porkchop]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Stuka:
That sucks PC. I knew the front output on a D18 was alot closer to the center then a D20...but didnt think it was that much.
<HR></BLOCKQUOTE>

The D18 and the D20 have the front output the same distance from the center (I am using a D20 case). The problem comes from the fact that the D18 front output is on the shifter housing so that causes it to stick out about 5 inches further and closer to the tranny.

I would think that the three piece shaft would be strong enough to work for the front. I am still thinking of how to make it work.

[Stuka]

Hrm...I though the D18 case was narrower then the D20 case as well. What I am wondering..is a D20 has the shifters comming out the front..your has them on the top...how does this work?

[River Beast]

Bryant....

Bummer!!!

I was thinking myself just yesterday that If I really needed a front CV now with a D20.... Not sure of that myself yet...hmmmm...but you said the shift housing of the D18 is part of the fron t output.... is that the sole reason for clearance problems?

I am almost ready to start my conversion over..... just a little more time.....

[gsmikie]

yo pc a drive shaft shop can make a small tube drive shaft with a cv or std u-joint that will clear the cj used a small dia shaft if you need a source let me know the last trick drive shaft we did was a flex drive but that is BIG bucks...............

[Erix Jeep]

I agree with Stuka, the 3pc shaft would inherently be weaker than a standard or CV shaft. If cash is not too critical, then gsmike's idea of the custom small tube shaft is ideal.

However, IF you are going with the 3pc shaft, then the only way it would work would be with the spring. I will try and draw something up, but I am thinking of a heavier duty spring INSIDE the sliding middle tube section. Actually, would need a center point of some kind in the middle section, with a spring on either side for the centering action. (Pardon my online brainstorming!)

[scotty]

cept that his tube is not the prollem. hes having trouble with the cv itself hitting the tranny...

[Kenall]

remove the xcase
remove the xcase-tranny adaptor
re-index the xcase-tranny adaptor one bolt hole clockwise (as viewed from the rear)
re-assemble.
construct nu xmember.
curse that u dint just get a QT

[porkchop]

Stuka, I will post the pics on my site again.

Todd, If I was running the D20 I would not have any clearance problems. The front output shaft is the problem.

Ken, I think it would cost more and take longer for me to constructed a new xmember. How would the t-case even mount up?


I think I have it all figured out. I have a high angle yoke that I am going to put in the front and that will give me the room I need to put on a regular shaft with out the cv. I will still have to have the shaft made from all of the ones in the garage. I also have to have the rear shaft extended. Is it better to extend a shaft or shorten one? I can do either since I have to rear shafts. I just need to get it all together. Hopefully by the end of the week.

[Erix Jeep]

Scotty, the 3pc shaft was just an idea to avoid using the CV.

Porkchop,,, MUCH cheaper to have a shop shorten existing shaft than to extend one! To shorten is simple cut and reweld/balance. To lengthen one have to add a section, and two welds, then balance. Just my two cents worth!