corporate 12 bolt into an 85 1009 help

[steve87]

I have an 85 1009 that needs a new rear axle. So being in college and not having a lot of money, I found a civi 82 (i think) blazer that is being parted out. It has a 12-bolt corporate in the rear and not sure whats in the front. I have pics, ill post them when in get home in a few hours. The truck also has a 6 inch lift. Im looking to buy both axles and the lift kit. I know nothing about lifts and have no idea who manufactured this one.

My questions are:

Will the 12-bolt rear fit under my 85 1009? Is the 12-bolt a good option?
If they both fit, i will plan on installing them but do i have to change anything to my transfer case or transmission bc of the new gear ratio?

If the 6in lift is off of a civi, will it work on the heavier CUCV? Is 6- inches too much? Im not looking to do much offroading (just dirt roads) with it.

I have a few more questions that ill post when i get back home.

Thanks for the help.

 

[wikallen]

Should be a simple bolt in swap. Grab the drive shafts as with a 6" lift, they might have put in longer drive shafts.

12bolt gives you a bigger ring, but smaller pinion over the 10bolt, so probably not much difference in strength. I would find out what gear ration they have in the axles, and decide on what size tire you are going to run. With no hard core wheeling, and the low power of the 6.2 you could probably get away with running 37s, 35s for sure.

 

[jdemaris]

I found a civi 82 (i think) blazer that is being parted out. It has a 12-bolt corporate in the rear and not sure whats in the front.

Will the 12-bolt rear fit under my 85 1009? Is the 12-bolt a good option?
.

An 82 Blazer won't have a 12 bolt rear unless someone swapped it in there.
So, I assume it's a 79- 81 Blazer. The pinion flange probaly takes a different u-joint than your Blazer takes. 1972-1981 Blazer take a #369 joint and a 1982-1991 takes a # 534G if automatic and a #331 if manual trans.

12 bolt has the exact-same load capacity as the 10 bolt. It will bolt right in all right. You've got to get the ratio you want. and change the pinion flange- and you have to be careful doing that or you'll ruin the pinion bearings.

Are you anywhere near central NY? If nearby, I'd give you a 10 bolt rear in good shape from an 86 diesel Blazer - with 3.08 ratio. I just yanked it out of one and stuck in a corporate 14 bolt rear from a 3/4 ton. 14 bolt axle is an easy way to get 8 lug wheels and extra load capacity in a Blazer.

 

[steve87]

I'm in Utah, thanks though. If i get the whole axle plus the driveshaft do i still need to mess with the pinion. The blazer has at 208 tcase like mine so it should fit. right?

Also, i don't have enough money at the moment to get larger tires. I have 31 on now, so i know it will look weird until i get can get some 35s but i wont be doing any damage running the 31s right. I would just get horrible mpg?

 

[ODdave]

I may have missed it but what makes you think the 12 bolt dose not have 3.08's? I have seen them withe 2.73 (iirc) before so you better check them

 

[jdemaris]

I'm in Utah, thanks though. If i get the whole axle plus the driveshaft do i still need to mess with the pinion. The blazer has at 208 tcase like mine so it should fit. right?

Also, i don't have enough money at the moment to get larger tires. I have 31 on now, so i know it will look weird until i get can get some 35s but i wont be doing any damage running the 31s right. I would just get horrible mpg?

That old Blazer has a 12 bolt rear and a 208 transfercase? I have never seen one like that. I've got a 79 and an 80 here. Both have 205 transfer cases, 12 bolt rears, and the slip-joint built into the driveshaft - unlike the 1982-1991 Blazers.

Bigger tires give worse fuel mileage. Best mileage is with standard 235/75-15" tires.

 

[jdemaris]

I'm in Utah, thanks though. be doing any damage running the 31s right. I would just get horrible mpg

Any military suplus dealers in your area? I know there are brand-new 10 bolt, 3.08 axles from military Blazers for sale all over the place. Usually around $400, front or back. For $400, I could buy a complete diesel Blazer - but depends on what you can find and how much money you want to spend.


Rear Axle Assembly, Chevy/GMC, U.S. G.I. [750201] - $395.00 :: Colemans Military Surplus LLC - Your one-stop surplus store with Army/Navy products for hunting gear, camping gear, emergency products, and survival products

 

[southdave]

I going to wake this thread up, I have d44 and 12bolt out of K20 burban. I believe 3.73. I put 700r4 in my 1009, and I am not please with it. I drive it 3 rd gear alot, and that heats up tranny.. I assume that it a direct bolt up and the stock drive shafts will not be an issue?

 

[Recovry4x4]

Should be a direct swap. The exceptions may be the rear emergency brake cables. Older ones went down each side where the CUCV stuff came around and up the drivers side.