Dana 44 and Corporate 12 bolt..One in the Same??

[equalizer]

Hey guys, I was going through the LCm truck cataloge and just had a question. I ve got a 72 blazer, and what I was wondering was why did Chevrolet not opt for putting the Dana 44 axle in the rear of 4x4, just the front. Is the Corp 12 bolt and Dana 44 one in the same. Any ideas would put the issue to rest

 

[POWERMAD]

They are not the same axle.
Older rigs like Cornbinders and such had D44 rear axles.
As to why.. the 12 bolt was pretty much the norm in light GM rigs as the Ford 9" is to their line up.

 

[atho]

GM did use some dana 44 axles in the rear of some of their 4x4's, but they saw very limited use (much like the semifloating dana 60 rearend that some half ton 2wds had).
I have seen 3-4 '67 and '68 GMC 1/2 ton 4x4's with a rear d44 from the factory. Never a Chevy, though, and only those 2 years. /forums/images/graemlins/dunno.gif

 

[Josh Northrup]

What rear-end would on my 88 k5 would it be a 12 bolt

 

[blazinzuk]

No 12 bolt was phased out in the late 70s.

From then on it was a 10 bolt

 

[rampage]

No 12 bolt was phased out in the late 70s.

From then on it was a 10 bolt

Unless someone put a different axle under it at some point. Just count the number of bolts on the diff cover.

 

[sreidmx]

I thought the 12 bolt had a larger ring gear??

 

[Bent77]

I thought the 12 bolt had a larger ring gear??

Slightly. Different sizes clear through on stuff. Nothing of super consequence or usefulness though

 

[sreidmx]

So whats the big deal about 10 bolt vs 12? is the axle larger or bearings?? semifloat?? what?

 

[Bent77]

10 bolts die easier, but axle and bearing sizes are comparable.
Both sf

 

[diesel4me]

The 12 bolt pinion is actually smaller at the bearing I.D. I believe,so many claim they are no better (and maybe weaker) than a 10 bolt,for that reason...

That said,I had 3 of the 12 bolt rears under 70's GM trucks and had zero problems,other than one stripping the pinion yoke splines out,which was my fault for doing burnouts in 4 low without locking the front hubs....

My '85 Burb has a 12 bolt rear,and as far as I can determine,its original to the truck--I've seen some other 1/2 tons with a 12 bolt from 1980-86 "factory",so I think GM used up what they had left over,after the supposed "cut off date" of 1980 or so..

 

[warrpath4x4]

I had an 87 Chevy 1/2 ton 4x4 and it had a 12 bolt rear from the factory