6 lug to 5 lug
 

I have a 1972 with a 308 rearend and want to change to a 373 rearend. My neighbor has a 1970 6 lug 373 rearend and was wanting to know if I can take my 5 lug axles and put them in the 6 lug rearend.

Are the axle splines different? Is this possible and if so what concerns / issues will I run into? Both are 12 bolt rearend.

Thank you for reading and thank you for taking your time to answer my questions.

Re: 6 lug to 5 lug
 

The 5 lug axles are usually longer than most of the 65-70 6 lug axles. There were some 70 6 lug axles that were made in the same width as the 71-72 5 lug axles, but not very common to find those.

If swapping axles doesn't work, you can swap the carrier and r&p between the two

Re: 6 lug to 5 lug
 

Every 6-lug 70 axle housing I’ve run across has been the same width as the 5-lug 71-72 housings.
Measure the two and if they are the same width, the axles can be swapped.
I would look closely at your 5-lug axle bearing surfaces.
This is a good time for new bearings and axles seals.

Re: 6 lug to 5 lug
 

Moser will cut fresh axles for you in any configuration you can afford.

Re: 6 lug to 5 lug
 

What Orange sunshine said.....I have Moser axles in my truck (75/12 bolt), & they were a stock item. I would bet that the axles you have will fit the early diff.....but if not you can measure & order the proper lenghts. It has been a few yrs back, but the axles were not that expensive (about $260 shipped, with studs). We all know that prices have gone up over the yrs....but also check other manufacters for prices....as said , many of the popular C-clip axles are , or were in stock. Longhorn:chevy:

Re: 6 lug to 5 lug
 

When I rebuilt the 12-Bolt differential from my '67 K/10 Suburban, the GM plant that made them was on strike. New OEM axles were unavailable. The diff shop said, try Moser.
I called them, and they were able to cut me a new pair for the same money as stock. When they came in, I was concerned that the outside diameter of the flange that mounts the wheel studs was over an inch smaller. Moser said they were guaranteed for life.
That rearend, with an added Auburn posi served under the Sub for about 3 years. Then an engine fire [and being Totalled with a Salvage Title by the insurance company] grounded the Sub.
In 2010, the 12-Bolt 3.73 Eaton posi under my '71 Jimmy lunched out. We cannibalized the Sub's diff for the Jimmy. Still running good for 12 years.

Re: 6 lug to 5 lug
 

Moser has 5-lug "replacement" axles you can buy that fit the narrower 6-lug housings. I put a set in a 1969 12 bolt housings and they worked perfect.

Gary

Re: 6 lug to 5 lug
 

I have a 70 diff 3.07 or 3.08 in my 66 C10 and the axles are wider so I think you are good to go with what you want to do.