Name this Posi Unit

[mountainexplorer]

I was pleasantly surprised to find the '91 GMC Crew Cab I got had a Detroit Locker in the 14-bolt rear. The front 60 has spider gears but looks like clutches on the sides.

Who can name what sort of Posi this is? (Pictures attached)

 

[JEBSR]

Thats what was in my 60 when I bought it, looks like an eaton unit to me but from what I can gather on the net Dana/Spicer makes it.

 

[walla2k5]

I had one like that on a 44. I think it's called a Trac-Loc or something.

 

[K5MONSTERCHEV]

Yep thats a Trac-lok.

 

[b454rat]

x3.

 

[thatK30guy]

X4...

 

[mountainexplorer]

It's a 3.73 ratio front. I'm thinking use it for my snow plow truck which won't run larger than 33" tires. I'm thinking turning 36-40" tires wouldn't be the best for a Trac Lock

 

[thatK30guy]

At least with that ratio, you can actually DRIVE it on freeway speeds.....

 

[mountainexplorer]

yeah, if it was a stronger posi unit I was thinking of having to swap gears and all that to run it in one of the bigger trucks. But beings that it's 3.73's and already set up, I could swap it into my plow truck which is just a frame sitting here anyways.

But the matching 3.73 rear has a Detroit which I'd rather not run with the plow truck. The current rear end is a Gov-Lok with 4.10s... I wonder if I could just switch ring and pinions... carrier's the same in a 14-bolt between 3.73 and 4.10 if I remember right... so I could put the 3.73 rear ring and pinion onto the current Gov Lok carrier and use the matched 3.73s in the plow truck, which would be a 454/TH400/205 and 33" tires or 235/85R16 studded snows in the winter.

 

[K5MONSTERCHEV]

Thats actuallty intresting to see a 60 front with a trac-lok instead of a powr-lok.

The problem with the trac-loks is that they break clutches, but im talking about in a rwd vehicle with 70K plus miles on it, such as Dodges with a 9 1/4" rear end. You'r 36's should be fine.

 

[mountainexplorer]

It's probably not worth the hassle to tear it all apart and swap gears in it to run the Trac Loc in one of the trucks with bigger tires. I'd probably have to run 4.10s to be able to use the same carrier, or have to buy thick cut gears.

And I'd probably find a way to break it with larger tires.