Can Semi-Float Rear Axle Handle a Lunchbox Locker or Limited Slip?

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DoubleDingo

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3/4 Ton axle, semi-float, currently open diff, can it handle a locker or limited slip without grenading?
 

Zelph

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Yup. Will handle a ARB locker spinning 35” tires.
 

Radiohead

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3/4 Ton axle, semi-float, currently open diff, can it handle a locker or limited slip without grenading?
I'm counting on it ;)

Sticking with the 4.10's or are you gonna stretch out your legs some? I'm seriously considering 3.42 or so.
 

DoubleDingo

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I figured it could. Good to hear it can. 2wd truck, not abused, but sometimes worked. Have considered going to 3.73. I wish 3.55 was an option, that is a great ratio. 3.42 is too high for a c20, 3.54/3.55 is about the tipping point for useable power with a 350. This being a vortec 350 with the 300hp/327 cam may help at that 3.55ish ratio.

4L80E with 4.10 is an option.

Mainly kicking around having better traction for the times we end up off the beaten path.

Side story: We were camping with Crusty Biscuit, had planned to do some bass fishing before heading back to camp, since we were traveling past that area to get back to camp, and bass is a great meal.

Took a wrong turn, ended up on a very sandy road. 2nd gear and steady throttle got us through, but sometimes it was bouncy with traction loss. Had to backtrack out of that mess. Crusty Biscuit has a factory Detroit locker, it got us through. I am a firm believer, from experience and otherwise, that if it was open diff, we'd needed a tow for a few hundred feet just to be on our way.

Triple digit heat, wife, dogs, being stuck and waiting, when driving out is possible, driving out is always best.

The '81 is very capable from what paces I've put it through. I am just looking to make it more capable. Not 4x4 capable, I know the limits
 

BKING33

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I have a Detroit True Trac in my 3/4-ton Burb. Has over 30K miles on it now. Only had a problem with it on ice one time,
but that can be expected for any setup. Mine is a 2-wheeler as well.
 

Strick

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My old '81 K20 Sub has a SF14 3.42 LSD. It has 35 Buckshot Mudders on it now and gets wheeled around here quite often.

HS
 

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4L80e sure takes care of the highway high rpm blues.

Which for some is the gateway drug to an LS swap. Lucky I'm immune
 

Craig Nedrow

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3/4 Ton axle, semi-float, currently open diff, can it handle a locker or limited slip without grenading?
DoubleD, I have a Yukon lunchbox locker, 4:10 350 turbo, 454, 12" 33's and it has been unbreakable. Off road, with big loads of wood, untold burnouts, it has never let me down.
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Start at post 35 for a pictorial install of befor mentioned locker.
 

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Fat 454

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yer - got some toothpicks in the back of that 'un alright ..
 

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