Driveshaft guidance needed...

[Twiztedmods]

Just finished up with the 5.3L and 4L80/241C with a JB conversion SYE conversion... A little bit about the K5, I have a 60 front and a 14 bolt rear, i'm sitting on DIY4X front B52's and a rear shackle flip with 56" springs. I'm also using ORD's zero rates with the rear set as far back as possible.

Anyway, I have a 1350 flange on the 241C and a 1350 yoke on the 14 bolt. How do I measure for the a correct driveshaft? Currently I have 7* on my transfer-case and 14* on my 14 bolt pinion, looks like I need about a 38.25" driveshaft. How do I determine the correct pinion angle for optimal performance?

I did google search and I am thoroughly confused...

Any help would be greatly appreciated, trying to get this figured out before I have to go back out to sea. Anyone on the USS John C. Stennis (CVN74)?

Thanks for the help.

 

[blazinzuk]

As simply as possible.

Without a CV the angles need to be within a couple degrees of opposite. If your 241 flange is pointing 7° down your 14 bolt yoke should be pointed 7° up.

A CV driveshaft is different. The yoke needs to be directly in line with the driveshaft. So you could draw a straight line from the driveshaft through the yoke of the 14 bolt

That help?

 

[skunked]

Good info here with some pictures

http://www.4xshaft.com/

 

[pblaze725]

I've worked with 2 different driveshaft guys and they had me measure the length 2 different ways.
I would ask the guy who is who is working on it how he wants the measurement taken.

When I watched tech 1 measure my driveline angles he set the pinion yoke vertical and put the angle finder on the flat edge to determine the driveline angles.

At the Tcase he did the same, he rotated the slip yoke until it was vertical and put the angle finder on the flat surface where the cap is.

Tech 2 put the angle finder directly on the output shaft and on top of the pinion.

In the end their calculations were the same.

Tech 1 had me measure from the end of the output to the front of the pinion yoke and subtract .75".

Tech 2 told me to measure directly from the output to the back of the pinion yoke and don't subtract anything.

Both tech's did an excellent job but they took their measurements in different ways. Like I said check with the guy that's going to build it so you are on the same page.

 

[Twiztedmods]

Thanks for the guidance! I'm going to order my driveshaft from Tom Woods. Awesome customer service.

 

[muddermilitia]

As simply as possible.

Without a CV the angles need to be within a couple degrees of opposite. If your 241 flange is pointing 7° down your 14 bolt yoke should be pointed 7° up.

A CV driveshaft is different. The yoke needs to be directly in line with the driveshaft. So you could draw a straight line from the driveshaft through the yoke of the 14 bolt

That help?

I was always told with a cv shaft, to point the pinion like 1 or degrees down to compensate for axle wrap under hard acceleration so that (in theory) it straightens out when you are hammering on it

 

[jeff in co]

I was always told with a cv shaft, to point the pinion like 1 or degrees down to compensate for axle wrap under hard acceleration so that (in theory) it straightens out when you are hammering on it

I was told by Denny's that drive shaft angles don't matter. I kept telling him what I thought (about 1 degree down or so) and he didn't really want to hear it. His view was that the pinion needed to be aimed at the bottom lip of the seal. No angle's specified.

I also spoke with Tom Woods and he was very nice and easy to work with. He recomended a SYE for a long term solution and offered it for around $725 with 1350 CV driveshaft. So, I'm saving my money to get that...probably next month.

 

[skunked]

I was always told with a cv shaft, to point the pinion like 1 or degrees down to compensate for axle wrap under hard acceleration so that (in theory) it straightens out when you are hammering on it

I've had multiple shops tell me the same thing.

 

[pblaze725]

I've had multiple shops tell me the same thing.

Me too. ...Unless you have a traction bar.

 

[blazinzuk]

I was always told with a cv shaft, to point the pinion like 1 or degrees down to compensate for axle wrap under hard acceleration so that (in theory) it straightens out when you are hammering on it

I try to get within 2° for the simple fact that I am not using a digital angle finder. Using an digital angle finder I would in fact go 1° down.

I have found if your within 2 or 3 degrees your usually fine. If you have street tires and or smaller tires it becomes way more important. If you have 40" swampers you got vibes anyway.