The Stovebolt Site Forums The Shop Area The HiPo Shop 3/4 ton spindles on 1/2 ton dropped axle

Boy I know we've compared these axles a number of times but as long as some still like to discuss it I'm going to ask.

I can buy a 1/2 ton dropped axle(55 2nd series)but it's going on a 3/4 ton truck..i want to retain 8 lugs. I want to put this axle assembly together ahead of time and then swap it with the original. I've notice the 1/2 ton and 3/4 ton axles have different king pins...Can I assume that a machine shop can work this out...probably using a 3/4 ton king pin set on the 1/2 ton axle.

Thanks,

Keith

Well, if I was a betting man, I would bet large sums of money that the 3/4 ton king pin is wider than the 1/2 ton king pin. that being said, it would not be practical to bore out the eye of the 1/2 ton axle, because you would be begging for failure. You may be able to have the 1/2 ton kingpins bushed to fit the 3/4 ton spindles. Of course I don't know off hand the actual dimensions of either kingpins or spindles. Are the king pins for 1/2 and 3/4 tons the same height?

John

CAn't tell you yet about the heights John..I have a set of 3/4 tons comming and I already have some 1/2's. I can compare when I get them.

Thanks,

Keith

I just found out that the 1/2 ton is .865 dia the 3/4 ton is .921. Both are the same length. Not a big difference.

Keith

Ya it seems to me it should be doable..It is puzzling thou..the 3/4 ton kingpin is sold as being .921 dia...the 1/2 ton is .875ish.The guy who is going to drop this(Sid) says he has a 3/4 ton axle but it has an .875 pin hole. I'm sure this is easily workable..but rather than fight alligators I'd rather drain the swamp and just use spindles and an axle that came from the same assembly...of course I may change my mind tomorrow..

Have a good weekend 2count..looks like a hot one..95°Here

Keith

I was running a 3/4 ton rear end for many years, and my solution was to make a 6 stud to 8 stud adapter plate that just bolted on to the 1/2 ton hub. I looked seriously at adapting the 3/4 spindle to the 1/2 ton axle, but decided against it because I felt that it would be too difficult to get the job done accurately.
Bob

Bob I think I've come to the same conclusion..Although I think this is doable by any competent machinist..I want to minimize surprises down the road..you'll get plenty of surprizes anyway..I bought extra 3/4 spindles-I can buy the axle that went with them for $40 buck and have it dropped...Job done.

Have fun,

Keith

Keith, It wasn't that difficult but I do own a 12" lathe. I just traced out both patterns, so that they wouldn't interfere with each other, on a 8 inch diameter circular plate of 1/2 inch steel, drilled and counterbored the holes for the 6 bolt pattern, installed 8 new bolts for the 8 bold pattern. I counterbored the back of the plate for the 8 bolts so that they would be flush with the plate. I drove around on them for over 15 years with no problems.

I don't see anything wrong with your proposed solution, I would look at doing it your way with the idea of being able to install a radial thrust bearing to improve the ease of steering.
Bob

Couldn't you just ship it to Sid at Dropped Axles to drop your 3/4 ton axle? Or does he only do 1/2 tons?

yes I could lazy..I want to have a dropped axle assembly on hand so when I take the old one out I can immediately put the dropped on in..Probably saves about 3 weeks..Maybe I'm just too impatient..but you are right I could..The extra parts will eventually en up on Ebay..

Have fun,

Keith

Keith