Sourcing a posi unit

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GMFORLIFE

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HotRodPC

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You will be so impressed with this system. After a while you will realize money well spent. But you'll be spoiled too.
Every other truck will seem lame.

So you're running a 205 no doubt? With twin sticks...
I mean why wouldn't you at this point?
FWD anyone? That F doesn't mean Four btw..


That is the plan. I was thinking 700r4 and NP205, but the more I think about it, if I can go 4in lift and 33 in tires, do I really need the OD? I think I'd rather have the durability of the Th350 than the OD. Though I'd really like to experiment in beefing up a 700r4 too and having a deeper 1st gear also is another advantage as well as the OD. So I'm still torn on the transmisson choice. And for sure, if I go with the NP205 for damn sure will be twin sticked, and the ARB air locker, can you say, Front Dig?!?!?
 

HotRodPC

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The other big advantage to True Trac, is the fact that is does NOT have clutches in it as he said. Those types that have clutches, are very similar to Auto Transmission Clutch packs, they do wear out. When they do, then your system needs rebuilt. I've never had any luck finding clutch disks to rebuild a LSD unit. Another reason I just prefer lockers. Yep, they're noisdy and a PITA as times, but I don't really care. It doesn't bother me so long as I know that's what it is.
 

HotRodPC

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This guy here is full of ****. LSD DOES NOT have clutch packs like a manual transmission. Clutch packs like an Auto Transmission YES. And to wear out in 20,000 miles is ********. That would be a very extreme case, but I'd say 75,000-100,000 miles is more reasonable. He's obviously just trying to sell Torsen units.
 

shiftpro

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That is the plan. I was thinking 700r4 and NP205, but the more I think about it, if I can go 4in lift and 33 in tires, do I really need the OD? I think I'd rather have the durability of the Th350 than the OD. Though I'd really like to experiment in beefing up a 700r4 too and having a deeper 1st gear also is another advantage as well as the OD. So I'm still torn on the transmisson choice. And for sure, if I go with the NP205 for damn sure will be twin sticked, and the ARB air locker, can you say, Front Dig?!?!?
Oh so many choices...
I can't remember... you have a big engine? Because you're thinking along my lines with using a 700. Now I stumbled (few years ago) on a great deal for a built up 700, so I nabbed it. Was thinking finding a 27 spline 205 to go on it. Well... here in BC most guys were buying and ordering 4x4s with 4 speed, so a 27 spline 205 is a little rare. In Alberta and Sask there are more... flatlanders were buying lots of auto K1500s.
Now the reset... I want to save my 700 for a lighter duty daily driver build after my one ton BB is done. I can't help but notice that
the stronger 4l80 is plentiful and cheaper to rebuild (or build up for that matter) than the 700... and the price of electric controllers (for the 4l80..E..) has gone gone to about $300?
Anyway I decided to not take the chance on my 700 with my 496 in front, really really wanting to unleash from time to time.

So my friend the moral of this story is why not consider a 4l80 instead of the 700. But you're building a locked up one ton with only 33"s... hmm. Yeah you don't really need deep gears. What the hell, go big anyway!
 

HotRodPC

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I have a 350 to build fro this truck project, but it's likely going to get the Stock OEM 454 out of my C20 since I'd rather have my 4x4 project than the C20 project. Kinda going to consolidate both projects into one. I was kind of hoping a stock 454 with 4.10's and a being sensible with 33in tires should be able to get a 700r4 alive. Though as said, I'm a bit torn. I know the Th350 will be plenty reliable and durable. It's not intended to be a daily driver so mpg isn't extremely important, but alot of the fun in the truck will be had at my dad's 70 miles away, mostly highway with 70mph speed limit, so to be able to get it to my dad's I'd like to get a least a little mpg and be able to cruise at least the speed limit so that makes me think 700r4. I'd damn sure give it a try, but it'll cost for the 2in spacer, and getting driveshafts made. Then if I change my mind to go Th350, I'll have to remake driveshafts. The NP205 I have, is the fixed yoke rear too, so it'll have the big slip built into the driveshaft. I've got a dual cardan front driveshaft but it'll need worked on too.
 

GMFORLIFE

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My turbo 400's never wear out.
Im going with the truetrac.
Awesome design..anyone can see it.
 

4WDKC

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342s, with 33s was 2500 ish rpm at 70 in drive 410s add 700 ish more rpm to that, and for what it cost to build a 700 to withstand the 454 you could buy and rebuild a 4l80 and get the controller if you went that route. I have read the 0411 ecm can be converted to a stand alone controller.
 

Jrgunn5150

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I have read the 0411 ecm can be converted to a stand alone controller.

It can, it'll take someone with HP Tuners or EFI live and the credits, still cheaper than a microsquirt controller though.
 

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