[lolife99]

Originally Posted by cdowns

about the only thing you can do is buy another newset of axels and measure to make sure they are correct this time

the 69-70 6lug axels were wider than the 67-68 sounds like that is your problem

This is incorrect.
The 71-72 axles were wider than the 67-70 axles by approximately 3/4" per side,... with the following exception

Originally Posted by Robznob11

i know of no 70.5 and up rears that had 6 bolts if it is a newer rear they would have had to get custom longer axles with 6 bolts wich is unlikley sounds to me like you got sent the wrong axles and im not positive but im thinking there is only 3/8 diff in the length of the 68 and 72 axles

There was a transition year for the 6-lug rearends in 1970.
Although kinda rare,... I do own a couple of them.
(one leaf spring GMC and one coil spring type that's in my 1970 stepside.
And I know it's the original rearend)

Most don't talk about '70 model rearend when talking 6-lug vs 5-lug,... because it adds to the confusion.
But at some point in the 1970 model truck,... your truck could have had the narrower 67-70 housing or the wider 71-72 housing.

The narrower rearend should measure approximately 55.5" from "backing plate to backing plate".
The wider housing will measure 57" from the same point.