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Old 07-27-2019, 03:34 PM   #1
CG
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3/4 Ton Blazers

If you did this mod to your Blazer why did you decide to do this?

Did you break the stock half ton axels? Not really a mod Ive seen a lot of while going through the Blazer section of the board. See plenty of half ton pics of folks out playing on the trails and such.
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Old 07-27-2019, 06:18 PM   #2
franken
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Re: 3/4 Ton Blazers

The people who wheel seriously break stuff and put beefier diffs in, though they often skip the 3/4 ton and go to tons.
This isn't limited to Blazers. Spend some time here: https://www.pirate4x4.com/forum
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Old 07-27-2019, 06:43 PM   #3
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Re: 3/4 Ton Blazers

Just find a decent m1009 CUCV. They are 1 tons from the factory. However I've seen the "wimpy" dana 30s, 44s, and Detroit 10 bolts take some punishment and survive. They can also be built to far more robust than stock. Don't put a good K5 drivetrain to waste. If you treat your vehicles with a level of responsibility, a stock K5 drivetrain should last you the rest of your life.
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Old 07-27-2019, 10:14 PM   #4
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Re: 3/4 Ton Blazers

I just rebuilt both the original 12 bolt and Dana 44 in mine. I have no plans to do any hard off roaring so I figured it was plenty. I did install chromoly axles just in case but I doubt I’ll ever need the extra strength. The diffs were in decent shape when pulled apart so nearly 5 decades didn’t take too much toll.
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Old 07-27-2019, 10:47 PM   #5
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Re: 3/4 Ton Blazers

I had broken the 12 bolt again and wanted not just better durability but the better wheel selection that the 8 on 6.5" brought.

That and I found a 3/4 ton sub cheap. My 8 lug swap with new wheels and tires was done for $1500 about 12 years ago.

I found another 3/4 ton sub even cheaper and it's axles are underneath my kids Jimmy project. His truck at least needed a new axle because the 12 bolt housing was broken from a wreck.

3.73 geared sub axles were less than buying just one ring and pinion to change gear in the stock 12bolt/Dana 44.
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Old 07-27-2019, 10:58 PM   #6
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Re: 3/4 Ton Blazers

I put a 4” K20 Suburban spring kit on mine. The front springs were bowed the wrong way from time and added bumper weight. Figured 3/4!ton springs were a good idea. Living in the city now, 20 years later, and regretting it because Houston roads are worse than most trails.
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Old 07-28-2019, 02:35 AM   #7
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Re: 3/4 Ton Blazers

Done it.

I thought it would be cool and, obviously, stronger.

But the reality is my K/5 is mostly a mall queen.

I used the same front Dana 44 but replaced the knuckles. I replaced the rear with an H052 locker axle.

There’s a few things I did that really didn’t need to be done... but I like my K/5!

Wil
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Old 07-28-2019, 06:56 AM   #8
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Re: 3/4 Ton Blazers

I did it because my 12 bolt got trashed from salt water jet ski launches. I found 4.10 gears in the one tons and figured it was cheaper just to buy the beefy axles instead of regearing. A guy in cali took my 12 in trade on a 14 bolt. Found the dana60 in a junk yard in a 20000 mile county truck hit in the rear by a tree. Sold my 44 to recoup some funds and I was set. Rear has some sort of locker but the front is open. The ride stability increased about 500 percent. No lie. Of course that could have also been the 10 ply swampers and the stiffer aluminum rims. Best thing I ever did to it but I wish I had put the longer springs on when I had the axles out. I didn't know about that mod yet anyway so it was the best I could do at the time. Well all the mods really. Went from 4x4 to 4x4 extreme.
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Old 07-28-2019, 09:35 PM   #9
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Re: 3/4 Ton Blazers

I put the military CUCV axles under mine. I like to overbuild things so I don't worry so much about breaking something out in a remote area. I think the stock housings with beefy internal upgrades would suit most people, just depends on how rough you are on your stuff. Check out my build thread to get an idea of what you need to do the swap.
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Old 07-29-2019, 10:14 AM   #10
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Re: 3/4 Ton Blazers

Would 3/4 and 1 ton axles put strain on transmissions and transfer cases intended for 1/2 tons?
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Old 07-30-2019, 10:37 PM   #11
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Re: 3/4 Ton Blazers

Quote:
Originally Posted by WyattTX View Post
Would 3/4 and 1 ton axles put strain on transmissions and transfer cases intended for 1/2 tons?
No. But it could shift the weak link further upstream, but if you have and SM465 and a NP205 you have 1 ton driveline anyhow.
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Old 07-31-2019, 12:47 AM   #12
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Re: 3/4 Ton Blazers

In the past I had converted 2 of these to 3/4 ton...kinda. All I really did was swap in a Dana 60 in the rear and convert the 44 front to 8 lug. I had an incident in my youth where I had a C clip break in the rear and the result was the shaft walking out of the diff which resulted in laying the vehicle on its side. Never had a C clip rear after that in a truck....always a full float. Why would they ever design a rear with a C clip holding the shafts in especially in a truck where you are destined to load, haul and tow?
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Old 08-03-2019, 09:07 AM   #13
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Re: 3/4 Ton Blazers

Quote:
Originally Posted by kwmech View Post
In the past I had converted 2 of these to 3/4 ton...kinda. All I really did was swap in a Dana 60 in the rear and convert the 44 front to 8 lug. I had an incident in my youth where I had a C clip break in the rear and the result was the shaft walking out of the diff which resulted in laying the vehicle on its side. Never had a C clip rear after that in a truck....always a full float. Why would they ever design a rear with a C clip holding the shafts in especially in a truck where you are destined to load, haul and tow?
THAT is a great question. I have never "liked" the design but I guess it keeps working so I leave it alone. Maybe that is the attitude they had back in the day as well. Maybe I should upgrade my 2WD to better axles and stronger C clips. I plan on doing some "accidental" drifting. Sorry occifer... Gotta say though once I upgraded to the floater and D60 I have done absolutely nothing to the axles and am very confident when driving that they will be up to anything I throw at them. I did have to put a spacer on the front axle on top of the Kingpin spring. I think it compressed a bit in the accident I had but a thin steel washer took up the play and tight as can be again for .25 cents and 20 min of east work. I did total the truck though...
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Old 08-05-2019, 08:11 PM   #14
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Re: 3/4 Ton Blazers

The c-clips themselves are not the weak link. The axle itself breaks and all that holds it in is the C-clip, so the broken part of the axle leaves the vehicle and that has the wheel attached!

The 9.5" semi-float 14 bolt is a c-clip axle and is rated at 5500# GVWR. Except for big power, big tires, and abuse they are more than sufficient for the application they were originally installed in.
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Last edited by Mike C; 08-05-2019 at 09:01 PM.
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Old 08-08-2019, 05:18 PM   #15
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Re: 3/4 Ton Blazers

1 ton conversion here ... bought a M1008 CUCV truck with very few miles on it for donor D60 front & 14 bolt full floater. My original stuff was worn & tired; we could do the swap/conversion ourselves cheaper than rebuilding & buying new parts/gears/lockers for 1/2 ton stuff, so why not. I like because it's basically bullet proof now; no worries if do wheel it hard. I'll probably never sell it it, but big advantage to 4x4 crowd and selling point if has this over D44 & 12bolt. But to be really honest, stock drivetrain is fine for trails & easy wheeling especially with narrow 35s or smaller tires in my experience.
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