Hey Guys, some driveshaft questions for 'ya:
I am getting ready to weld the pedestals on the 14Bolt and was going to use the carden joint from the old driveshaft. I started to point the pinion at the rear output shaft of the NP205 'til I realized that by doing this it would set the pinion at 25º! Besides looking silly, would this create any problems? After some thought, I thought I would just go with a conventional driveshaft with one u-joint at either end and leave the angle at 5º. After some more thinking (I'm starting to get into trouble with all this thinking) I am wondering what makes a "one ton driveshaft". The yoke that is on the 14Bolt has a u-joint that is 1-1/8 dia. x 3-5/8 width. The D60 has a 1" dia. x 3-5/8 width, which is what the old D44 had. I will have to buy two yokes for the NP205 as it came without them. If I am going to do the shafts right (one ton equivalent), what yokes and ears should I get to accommodate what u-joints to make one ton driveshafts? It seems to me that the carden joints are 1/2 ton equipment and also, a lot more expensive to replace when they blow up. Also, wouldn't you want to run say a Brute Force or some generic u-joint instead of running a "bulletproof" u-joint and keep that the weak link instead of snapping a pinion shaft, spinning splines or twisting driveshafts??? Questions...questions...any thoughts? Below is where the angles are right now. Driveshaft loops will be installed. Excuse the crude drawing...



https://www.ford-trucks.com/user_gallery/sizeimage.php?&photoid=9952&.jpg

 

You are more likely to need the double cardian joint on the front shaft. There are really mostly used to solve vibration problems. With any regular driveshaft (single u-joint) you will want the pinion angle set so that both u-joints operate at the same angle in relationship to each other. This causing the u-joints to cancel out each others vibrations.

With the double cardian joint you want the the pinion angle set so that the single u-joint has no operating angle (straight) so it does not cause any vibrations and the double will cancel itself out.

I hope I explained this okay.

 

Thanks Brian460,
Someone sent me a link and I talked to the guy and he is going to set me up with a 1410 for the pinion side, a 1350 double-carden for the NP205 side with a flange. I will be changing the angle in the back to 2º lower than the driveline (roughly 23º) for this type of set-up. Looks like about $700 for the rear alone.
I tried a broomstick and some duct tape but I didn't even make it to the mailbox so I guess I'll have to spring for this.
Probably get 1350 for the D60 pinion and a 1350 double-carden for the NP205 side but it looks REAL tight in there, but that'll have to wait 'til my wallet recovers. I got a few things left to do before I can run anyways.
Thanks for the response...

 

I wouldn't let my u'joints be the weak link. Have you ever had a joint break on the highway doing 75 miles an hour, i have, and it was one of the least pleasent experiences i've ever encountered. Not only did it trash the driveshaft, gas tank, bed of the truck but it threw the truck around pretty good. I was lucky and it was the rear joint that broke. I saw a guy flip his mustang end over end at the race track when the front joint broke and the driveshaft catapulted him.

RYan

 

Thanks for responding about the u-joint weak link question. You were the only one to address this. That is a spooky story and yes, I totally agree with you that when they go, they can be very dangerous. I my case though, I have ALWAYS ran driveshaft loops in any truck that I have lifted beyond factory. I am running 3/4" tubing for loops at both ends of both driveshafts. Now, bearing that in mind, what do you think? I have blown so many pinion shafts and twisted driveshafts and spun splines that I was thinking that it would be less expensive to replace the u-joint than these other items. I guess in theory that the u-joint is the weakest link, I guess I'll just run Spicer and accept it as my thrashing is more at fault that the strength of the components! Thanks.

 

well a broken joint usually takes at least part of the yoke with it as well. So a broken joint probably means your either having your driveshaft rebuilt, or a new pinion yoke installed anyhow. I'd say But spicer joints and be done with it. If your breaking pinion shafts, twisting axles and so on, i'd say its time for an axle upgrade. I don't know what your running for axles, but sterling 10.25 rear axles shouldn't break pinion shafts, I'd say you might want to invest in one of them.

Ryan

 

Oops..i missed that 14 bolt thing. Theres your problem...you've got gm parts... anyhow..how about dana 80 rear..or can we say rockwell....LOL...good luck.

RYan