Should I go POSI???

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J-SQUARED

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The truck is an 85 K1500/LB/REG CAB/350/400/208/6"/35's. Still has an OEM 3.08 open diff 10 bolt. Looking to re-gear and am questioning if I should just spend the extra money and put limited slip in while I'm at it. I actually have done very little driving of this truck as its an in process project so I have zero road use to go from. I think I will go with 3.73 or 4.11. Just would rather not have a 1 wheel peel machine in wet or loose traction environments if these are prone to do that.

Can anyone provide real world experience with different set ups related to my question. I have done a ton of online research and most everything I find is speculative and calculated rather than real world drivability.

I wont do any towing and it wont be a daily driver. Mainly a going to town truck and hopefully some shows if I can get it spruced up well enough. I guess that could mean some highway but limited at best.

Thanks
 

Ricko1966

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The truck is an 85 K1500/LB/REG CAB/350/400/208/6"/35's. Still has an OEM 3.08 open diff 10 bolt. Looking to re-gear and am questioning if I should just spend the extra money and put limited slip in while I'm at it. I actually have done very little driving of this truck as its an in process project so I have zero road use to go from. I think I will go with 3.73 or 4.11. Just would rather not have a 1 wheel peel machine in wet or loose traction environments if these are prone to do that.

Can anyone provide real world experience with different set ups related to my question. I have done a ton of online research and most everything I find is speculative and calculated rather than real world drivability.

I wont do any towing and it wont be a daily driver. Mainly a going to town truck and hopefully some shows if I can get it spruced up well enough. I guess that could mean some highway but limited at best.

Thanks
You do understand that 2 wheel peel in wet or slick conditions gets you sideways, backwards or off in the ditch right?
 

legopnuematic

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With 35s, I’d recommend 4.10-4.56. You could potentially get away with 3.73s, but it will feel pretty sluggish.

You may consider finding a GMT400 9.5 14b semi floater from a K1500, 6 lug. Significantly beefier than a 10 bolt, but you can keep your wheels and stay 6 lug. Perches and shock mounts will need to be relocated.

I’m not sure a 10 bolt would love 35s with a tight limited slip or locker.
 

gmbellew

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I like the eaton tru trac limited slip...

I'll echo above that 6in and 35s with a 10 bolt is a tall order. 2-4in and 33s is about the max I'd consider and i would regear to 3:73 or 4:10 in that scenario.
 

TotalyHucked

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I have the Yukon Duragrip in both my lowered '85 and my lifted '05 that's on 35s. They work very well, they're a clutch type posi, which I prefer. For your uses, I think this would be a great budget option. If you were wheeling hard, I'd absolutely go Eaton/Detriot TruTrac or locker, but for a fun weekend nice rig, the Duragrip would do very well and it's about half the price.
 
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xm20k

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You do understand that 2 wheel peel in wet or slick conditions gets you sideways, backwards or off in the ditch right?
Enough power and it doesn't even need to be wet, Oh the joys of a spool.
 

75gmck25

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I do remember the days of driving a 428 Ford Torino GT with traction-lok. Plenty of torque to spin both rear tires and swing sideways at just about any speed. It was a learning experience.
 

Grit dog

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The truck is an 85 K1500/LB/REG CAB/350/400/208/6"/35's. Still has an OEM 3.08 open diff 10 bolt. Looking to re-gear and am questioning if I should just spend the extra money and put limited slip in while I'm at it. I actually have done very little driving of this truck as its an in process project so I have zero road use to go from. I think I will go with 3.73 or 4.11. Just would rather not have a 1 wheel peel machine in wet or loose traction environments if these are prone to do that.

Can anyone provide real world experience with different set ups related to my question. I have done a ton of online research and most everything I find is speculative and calculated rather than real world drivability.

I wont do any towing and it wont be a daily driver. Mainly a going to town truck and hopefully some shows if I can get it spruced up well enough. I guess that could mean some highway but limited at best.

Thanks
If it’s just a Sunday go meetin vehicle and the axles don’t “need” work, it’s already a 4x4 so you can get out of the proverbial wet grass scenario. And highway gears are nice unless you’re going with big tires.
I might consider spending all that money on horsepower rather than re gear and posi. More real world enjoyment and can always re gear later.
JMO
Edit, sorry I see you said 35s. Ya maybe re gear.
 

J-SQUARED

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If it’s just a Sunday go meetin vehicle and the axles don’t “need” work, it’s already a 4x4 so you can get out of the proverbial wet grass scenario. And highway gears are nice unless you’re going with big tires.
I might consider spending all that money on horsepower rather than re gear and posi. More real world enjoyment and can always re gear later.
JMO
Edit, sorry I see you said 35s. Ya maybe re gear.
I like where your heads at with regard to dollars better spent on HP than dumping more into the rear end... Its a planned cruising around truck and my son will inevitably drive it to school a few times I'm sure.

I haven't really even dug into the motor. Seems to sound and run just fine so ill get some miles on it and see where I need to be.

I think ill swap em to 4.11's and call it a day..

quick Performance seems to have some good pricing and products it seems.

Thanks all!
 

Grit dog

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4.10s make our 86 move out pretty good with the heaviest possible tire and rim combo. But it also has 300+ big block hp. (Theoretically)
The gearing will be a welcome change for sure. Just a screamer on the highway at 70mph or more.
 
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