M1009 axles under a M1008

Hey peoples. I just bought my second M1008 and I am getting a set of M1009 axles this week for it.
I am making it a DD with 90% highway miles.
I see some people stating that the axle perches are different in the rear and some people say it's a direct bolt in swap less the conversion u joint.
What is the deal are the axles a swap or do I need to weld/move things?

The rear spring perches on the 10 bolt 1009 blazer axle are closer together that the 14 bolt 1008 axle.

So if I use a truck rear axle it should be the same ?

The K10/1500 pickups and Blazers of that series all have the same spring perch locations. The 3/4 ton and up trucks have the wider locations so unless you relocate the perches. . .

Also, not sure how common a 3.08 gear in a 3/4-1 ton were. . .

I found a 14 bolt out of a 3/4 ton Suburban that had the perches in the correct location for my 1009 but it came with a 3.73 ratio but I also had a D44 front axle in that ratio.

edit:
disclaimer:
This was a few years and many beers ago.

Here's the skinny on all this. All 1 tons and bonus cab (crew cab) 3/4 tons have 40.5" spring perch width center to center. Everything else has the 42.5" spring perch width. Shock mounts are different as well. Going to have to move some perches Westy. LOL, ChevyC60 bought an M1008 sight unseen (for the most part) and when he got it home, it had half ton axles. Sounds like an interesting project.

Also as an FYI, there were no all wheel drive 3/4 ton bonus cab (crew cab) trucks produced.

If there were, would they have been called a 3+3/4x4?

Forgot about the shock mounts

Recovry4x4 said:

Also as an FYI, there were no all wheel drive 3/4 ton bonus cab (crew cab) trucks produced.

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They made them in 1 ton though?

Wait. You still post on the site Westy?

FMJ said:

They made them in 1 ton though?

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Yes they certainly did. The Gov't (Air Force) bought many of them. I've owned 2 and wished I still had both. Kinda my personal holy grail to find one with a 6.2 (that I can afford).

Why not change gears in axils.

helm1008 said:

why not change gears in truck axils

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If the goal is purely highway speeds with the stock TH400 and stock 30" tires. The tallest gears for a 14 bolt is a 3.21 ratio. And very rare at that. It would also require a carrier change as well. It certainly would be more highway friendly. But not the 3.08's the M1009 has. Also he'd gain a weight loss and less rotating mass if MPG is the secondary goal.

I'd personally go for option C. 700R4.

Okay

helm1008 said:

out of curiosity how strong are them 10 bolts anyways what are they compared to?

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The "09" 10 bolts are just standard 1/2 ton chevy axles. Not nearly as robust as the 14 bolt 10.5 inch full floating axles.

And the detroit locker in a 14 bolt is 100x better than a gov-locker. Or gov-exploder as I call them from experience.

Well moving mounts is no big deal. I was just reading so much conflicting info. As of axles the truck came with 3/4 ton Dana 44 and a 12 bolt in the rear
This is going to be a highway truck with 265/75/16 tires and a 2 inch lift. No hard core wheeling or heavy duty towing. I got a set if axles for 200 in town. It's way cheaper to just replace the axles then to re gear. Also I can just use me 1009 spedo adapter and poof done..

Westech said:

Well moving mounts is no big deal. I was just reading so much conflicting info. As of axles the truck came with 3/4 ton Dana 44 and a 12 bolt in the rear

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Not sure where you came up with this?

The 12 bolt rear axle has always been just a 1/2 ton axle as well. Only available in 6 and 5 lug.

The earlier trucks had a Dana 44 front (same as 1/2 ton) however the spindles and hubs were 8 lug. The internal shafts were the same. The rear axle was a 14 bolt full floater. Then in the 80's, GM went to a semi floater 14 bolt. (9.5") The front turned to a corporate 10 bolt. Again, same as the 1/2 ton truck, just with a different spindle/hub. There was a heavier option as well that offered the 10 bolt front axle and the full float 14 bolt rear. The 1 ton uses the dana 60 and 14 bolt rear. (Sometimes a D60 or D70 rear if it was a dually) That was through out the years 73-87.

What M1008 came with a 44 and a 12 bolt? and wouldn't they be stronger then 10 bolt axles, and if you do weld them mounts on cool em slow.

Hey can I do build threads on this web sight? I'm doing a pretty nice build on a truck I would like to share with people its a 85 M1008 low low 18000 miles