Need to confirm axles

[Southpa]

I finally got around to measuring my rear end "width". I was reading in earlier threads that there were 2 sizes in 1970 half tons, measured between their respective "wheel mount surfaces". The early 1970 at ~62" and later 1970 at ~63.5" Mine is the latter at around 63 3/4.

OK, with that established can I take donor 5 lug axles from any 1971 - ? Chev or GM half ton truck?

[Southpa]

ttt , anybody?

[Hottrucks]

wiould like to know too..now I'm going to measure my axle If I don't have the short one I could use the extra 3/4" on each side to get my rubber off the inner fender lip

[swierker]

I'll take a stab at this although I'd like to hear some answers from others as well.

The length of a 71- up axle is 31 5/16" x 2 =~ 62 1/2 +~ 1" (the space between axles) = 63 1/2. Id say that you are good to do the swap.

The older axles are 30 1/2" I think. Which would make sense using the same equation to come up with 62" as you said.

I have a donor rear I think I might just use the axles from and put them in my 70 rear already on the truck. I think it's the wider one, but I've only measured from backing plate to backing plate and they are both the same. I will know soon, I just got the last of my parts today to do my drop/disc/5 lug conversion.

Dan

[swierker]

One other thing that I noticed. Every vendor I have seen lists the 70 axles along with the 71-up. I have read on here a couple of places that the width switched over sometime midyear on the 70.

So why do ECE, CPP, Moser engineering all list the 70 axle as the wider version? Can anyone confirm the mid year switch or are the vendors just "rounding" off the years?

[Hottrucks]

ANd

my truck is 6 lug?? 1970.. did they make them both ways??