Driveshaft length & u joint size

[6.9Redeemer]

Hello Oilburners! I've learned a lot from this site, a long time lurker--first time posting. I have a 1985 f350 single cab long bed, 4x2, c6 tranny, dana 70u rear.

I bought the truck with a Doug Nash (DNE2) underdrive unit already installed. I am reverting back to a stock extension housing and driveshaft. I went to a yard and pulled a housing, but I couldn't find a driveshaft for my 133" wheelbase.

1. How long is a stock driveshaft for my wheelbase?

2. What series u joint are used? Ive searched, and it seems to be 1350, but I want to make sure.

3. Where's a good site to buy a slip yoke for my tranny? I know I need a 31 spline c6 slip yoke, but this goes to question #2 what u joint series?

Thanks,
All help is appreciated.

 

[typ4]

Get a yoke and slip it in there, pull it out 1.5 inches +- and measure. then go hunting. Your front will be a 5-1203x spicer . rear 5-1204x . If my old book is right.

 

[6.9Redeemer]

Cool thanks! I didn't know they were 1330 u joints.

 

[typ4]

well they can be either , thats the problem. An automatic diesel can have smaller joints than a standard. No rhyme or reason with those trucks.

 

[chris142]

My truck has 3 joints and the one in the middle is different

 

[junk]

For me I've always had to match the U-joints at the parts store.

What ya doing with the doug nash underdrive?

 

[riotwarrior]

Smqller u joints on autos due to less shock loading of driveline...IMHO...no clutch dumping or zuch shenanigans...constant power through upshifts in auto vs enguaged dizsengauge reengauge...of std...and zo on.

Just what me brain fingers it out....

 

[6.9Redeemer]

@junk I'm probably going to sell my DNE2 and wiring. It currently functions flawlessly, the only issues are that it has a small leak out of the speedo housing and around the shift motor cover. I have the complete wiring, auxiliary transmission, and custom driveshaft my wheelbase.