Adding Limited Slip to 14b SF

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adamj

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My rear end needs a rebuild bad. At least the pinion bearing, not sure about the gears if they need to be replaced. Anyway, this is one of the few jobs I have decided to leave to the professionals. It doesn't have a very common gear ratio (3.42, 14b sf, open) so I have been having trouble finding a junkyard swap. I am very satisfied with the current ratio and tire config, do not want to go up or down with the gears or tires, so I am opting for a shop to do a rebuild, and it will have a warranty on it too.
My question is, what are the options for a locker/limited slip? While the shop has it up on the lift and the rear end disassembled, I would like to take the opportunity to add some sort of locking differential to the currently open carrier.
I assume a full locking unit is going to be more expensive, but what should I be looking at to install one of these or a limited slip type?
 

77 K20

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If you want one with excellent street manners and low tire wear I'd recommend the Eaton Truetrac. Not a true locker, but gets the job done without having to use friction modifiers to the oil and no clutches to wear out. Completely silent operation also.

This is cheaper than a detroit locker.


914A538

http://www.summitracing.com/parts/dtl-914a538


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Also note:

Detroit Truetrac
A quality petroleum (mineral) based oil is recommended. Synthetic
oils and friction modifiers should not be used, as they will decrease
overall performance.
 
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adamj

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Is that Eaton Trutrac considered an automatic locker? (I'm stlll learning about lockers and such)

You bring up a good point about clutch wear, so I will be looking for something without clutch packs as a wear item.
 

77 K20

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That differential isn't technically a "locker" as it doesn't lock both tires together. It would fall more under the category of a limited slip differential.

The detroit locker would be an automatic locker. When drivetrain is under power it will lock the 2 wheels together then when coasting it will unlock. A manual locker would be something you'd have to hit a button to activate (ARB air locker, or E-locker)

The truetrac transfers power nicely from side to side under almost all conditions by itself. The only times I've had mine not work when one tire was on ice with water on it (0 traction) or when I had a tire up in the air (0 traction). But to transfer some power over to the other tire you can apply the brakes to "force" some power to the other side. Basically it is recommended for everything except for rock crawling.

I've also had the Auburn Pro limited slip, the lockrite locker, the Gov-lock (GM locking differential G80) and a detroit locker.
 

SkinnyG

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I chose the TrueTrac for my C10. Weighing all the pros and cons of all the types of "limited slips," the TrueTrac is (in my opinion) the best for a daily driver. It feels invisible, but flat-out works!
 

adamj

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I did some reading into the trutrac, looks pretty good, but does seem expensive... How much more would a selectable locker (including actuation) end up costing me? If I'm going to spend $540, and it's a couple hundred more then I might go with a true locking diff, but this looks like a pretty sweet setup!
 

Georgeb

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My 2 cents.....If I had to choose I would love to have an E-locker. With no air system to worry about. No finicky snow driving manners and the ability to put power to both wheels when I want to in certain situations. I have only been stuck with my 2wd four times in 16 years and three of them were due to a loose nut behind the wheel. Three of the four times a locker would have gotten me out.
 

Fastereddie

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I just built my 14sf last month and i wanted to go e-locker but it was discontinued.. Went with the arb air locker and couldnt be happier. But your looking at a grand...
 

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