You need to put some type of limiter on each side to keep one of the sides from pulling out before the other side takes up the additional travel. Sounds doable, for a front anyway.

Jeff
89 YJ
If at 1st you dont succeed, your replacement will try and try again

 

jeff.. thats what the springs are for.. put them between the shaft and slipyolk on both ends..it will keep the shaft centered..

~~Elusive~~
/wwwthreads_images/icons/tongue.giftj-7..tellico tested, uwharrie /wwwthreads_images/icons/tongue.gifsafaried..1 ton drivetrain/wwwthreads_images/icons/tongue.gif..see it at http://www.jeepgod.net
oh yeah, and a 2000 tj,lift..etc

 

I like it! With a little trial and error, it may be a great way to double the slip yoke travel. Let us know how it works if you try it.

/wwwthreads_images/icons/cool.gif
'84 K20 driver
'80 CJ-7 BBC, 1 ton
'79 K10 mud racer

 

It sounds to simple, and that always scares me.
It should work though, provided you dont bugger up one side of the shaft on a rock lathe. I would fear that I would damge one side causing it to slip less readily than the other and the springs would not be enough to ballance them. I am brutal on front drive shafts in the rocks, I paint them before runs so I can see how bad I place them on rocks durring the day, They usually look like a barber poll after the first obstacle. I dont have any problems sepARATting, my front 10" slip slpine with my set up. It does seem like a very plausible design though,... just do it. Ill be there in the spring to tow you out of the tough spots if/when it fails(big grin).

Jeff
89 YJ
If at 1st you dont succeed, your replacement will try and try again

 

i dont think that will give you a whole lot of travel.. those stock splines arent that long.. and with the springs keeping it centered.. then you are basically doubling the amount of travel from which is inside the slip yokes.. 3" on each side would give you 6" of travel.. ...mmmm.. so if each side was say 6".. you would get per say 12" of travel.. 6 in and 6 out.. but i dont think the splines are that long.. would have to look at the one of many extras i got layin' around here..

http://www.jeepgod.net

84 CJ-7 401/T-18/D20/D44/D60w/4.10&Detriots/YJ frame & tub/35x16x15 Boggers
survival is instinct, but living takes guts

 

they are pretty close to 6" each.... 12" of travel is worth trying for....

~~Elusive~~
/wwwthreads_images/icons/tongue.giftj-7..tellico tested, uwharrie /wwwthreads_images/icons/tongue.gifsafaried..1 ton drivetrain/wwwthreads_images/icons/tongue.gif..see it at http://www.jeepgod.net
oh yeah, and a 2000 tj,lift..etc

 

have yall seen the emergency spare shaft on Pirate bbs?
its 2 inch square tubing inside of 2.5 square tubing, strong as heck, and as much travel as you want.

I think thats an awsome idea for cheap trail spare shaft!


OzarkJeep

"If thats the way that you want it, well thats the way I want it more..."

 

One way to get extreme travel driveshafts, is to use tractor pto shafts. A friend of mine has it on his highly modified yj. He just bought the inner and outer shafts and adapted them to his yokes. It gives him 24in of travel/wwwthreads_images/icons/laugh.gif is it strong? the shafts are for 400hp tractors! Two seasons with 36' swampers and a lead foot,and everything is still attached/wwwthreads_images/icons/smile.gif.

Ben

 

So a front driveshaft doesn't have to be ballanced like the rear? Or would an unbalanced shaft be only for slow moving trail rigs?

Jason

----------------
[]llll[] '90 YJ, NV4500, XD9000i, 35" MT/R, Snorkle, 4.5" RE lift, Tera Revolvers, etc. etc.

 

Only for a slow moving trail rig. Not to say how much it'd be out though, could be fine for slower speeds.

JEEPN
Winter Harbor, Maine
'81 CJ-8 Scrambled!
It's a Jeep, Chevy, IHC kinda thing!

 

As far as balancing goes, just take it to a Drive shaft shop and spend 50.00 to have it balanced. If the slip yokes are tight, you should be able to get a pretty good balance result.

I like the square tubing idea. But what about U-joint strength?
Mizu

 

I would rather the U joint give than the tube get twisted, U joints are an easy trail fix.
Id guess the square tubing is stronger than the normal driveshaft stuff, so the u joint would frag before the shaft twisted, as long as it didnt screw up the yoke it would be ok.

the front can be unbalanced if you have lock out hubs since it wont spin at freeway speeds, and it wont be a bad vibration at trail speeds when locked in.



OzarkJeep

"If thats the way that you want it, well thats the way I want it more..."

 

Anyone have a link to the square drive shaft at the Pirates site?

Jeepjohn
It's not what you bought,
it's what you built and
what you do with it!

 

here is the link, maybe it will work

http://www.pirate4x4.com/ubb/Forum10/HTML/006093.html

OzarkJeep

"If thats the way that you want it, well thats the way I want it more..."

 

http://www.pirate4x4.com/ubb/Forum10/HTML/006093.html