I'm picking up my 73 k5 tonight, the front drive shaft is uninstalled, I was wondering if anyone would know what size the bolts are to put that in?

 

You first may want to investigate why the front driveshaft was uninstalled...

 

i already know why it was. the guy thought it was full time 4wd.

 

I do not know about a 73, but my 85 has the U-bolts with 7/16" nuts on it.

 

is that on both sides?

 

yes. there is two on both ends of the drive shaft, two at the axle and two at the transfer case.

 

thanks i will check it out tonight when i pick it up

 

Yes, but with the NP203 full time 4wd in stock form, you cannot remove the front driveshaft and hope to move... Just trying to cover the bases so you do not end up with an unexpected problem.

And yes, they are typically are a hex nuts which require a 7/16" wrench (not a 7/16" thread) that thread onto a U shaped strap as pictured below:

This is a picture of the front driveshaft on my 74 K5 where it connects to the front axle (Dana 44). I believe that the other end is the exact same arrangement.

 

its not full time awd, he thought it was before. do you happen to know what thread pitch the bolts are?

 

It is a UNF thread. I do not know the exact thread size though.