6.9 with 4spd and OD $650 CL find

riotwarrior

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There is enough in parts, that if ya showed up with some greenbacks, I'd bet you would walk away with it for maybe...450 - 500 easily.

regardless of why it's pulled, that OD and all other parts are worth that small investment...

if it was a 4x OD I'd consider that. but it's not, it caps the 4x trans and makes it a 2x which won't work for me!


Good luck for anyone wishing to pu that setup!

Al
 

jaluhn83

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Calvin,

Why does it need the clocking ring? Everything I've seen (including USG literature) says it's a bolt on.

The GV does require an adapter - the front flange is larger 10 bolt design.
 

towcat

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Calvin,

Why does it need the clocking ring? Everything I've seen (including USG literature) says it's a bolt on.

The GV does require an adapter - the front flange is larger 10 bolt design.
i couldn't tell ya. all I know is that the oem ring came on the USG that I bought. I figured if someone went through the trouble of making something like that, there has to be a reason. I'm not here to second guess them.
 

jaluhn83

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Yah, that's good logic!

I bet it's a body clearance issue. It's splash lubed, so no real reason I can think it has to be mounted exactly level. When I get a chance I'll play with my USG and spare ZF and see if I can figure it out....
 

jaluhn83

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so usg and gv are different?

Yes. USG has a 31 spline female shaft input and the 6 bolt t-case style flange, at least the ones I've seen. The output is either a yoke or a 31 spline male / 6 bolt flange for 2wd and 4wd respectively. USG goes between the trans and t-case on 4wd. I have an installation guide for a USG 2wd version, but nothing for 4wd. Looking at the instruction it does appear that a clocking ring is needed as the USG adapter has the top bolt hole at 12 o'clock, whereas a 4wd flange has the 2 top holes at 11 & 1 o'clock.

GV has a larger flange size and more bolt holes, I think 10, plus a special adapter shaft.

USG is a quad countershaft constant mesh electrically shifted transmission - similar design to a brownie box. The GV is a planetary hydraulically shifted unit with a sliding cone clutch. Similar to an automatic trans. USG can be in either gear at any speed and will stay in. GV is hydraulically shifted into OD with spring return and the pressure is generated by an input shaft driven pump - so below a certain speed, (~25 mph from what I understand) you don't get enough line pressure to hold the unit fully in OD and it'll start slipping under load. The design is also not as heavy duty and I've heard it doesn't react well to engine braking. The GV design is a modification of the britich Leyland-Nash (I think, might have the name wrong) OD design of the 60's - originally made for british sports cars!
 

The Warden

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The GV design is a modification of the britich Leyland-Nash (I think, might have the name wrong) OD design of the 60's - originally made for british sports cars!
IIRC GV's design's a modification of a Laycock design...and the U.S. Gear design is a modification of a Doug Nash design.

I think you're right about the U.S. Gear being more stout; OTOH if something breaks, you're completely on your own...I'm still worried about what to do if a shift motor ever lets go...
 

towcat

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IIRC GV's design's a modification of a Laycock design...and the U.S. Gear design is a modification of a Doug Nash design.

I think you're right about the U.S. Gear being more stout; OTOH if something breaks, you're completely on your own...I'm still worried about what to do if a shift motor ever lets go...
if you're worried about that, I do have a Mitchell for sale :D
 

towcat

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I forgot about that...probably worth far more than I could dream of spending on it, but I'd be lying if I said the temptation wasn't there... :angel:

consdering that it does have most of the drivelines and crossmember braces needed......yea it's gonna hurt. :D
at least there's more goodies on the Mitchell compared to the brownie i'm locked into. that is the box only. I have to build everything else.
 

cr430c

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Wish I had the cash. I need a motor and would love the OD for my 94 I just picked up. If he has it in 2 weeks its mine.
 

jaluhn83

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IIRC GV's design's a modification of a Laycock design...and the U.S. Gear design is a modification of a Doug Nash design.

I think you're right about the U.S. Gear being more stout; OTOH if something breaks, you're completely on your own...I'm still worried about what to do if a shift motor ever lets go...

Sounds about right....

Understand your point on the USG, but on the other hand I bet 90+% of the parts are industry standard. Any wear parts at least should be pretty easy to find and replace, less so shafts and gears, but they shouldn't cause you much trouble.

Shift motor I think is actually a starter motor.

Even if does go out, it's a positive shift unit - so it should break in gear, not in neutral. Even if it does it'd be pretty easy to take the shift mechanism cover off and manually shift it into gear and lock it there.

IHMO, the USG box is much less likely to strand you and a much stronger design.
 

The Warden

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Shift motor I think is actually a starter motor.

Even if does go out, it's a positive shift unit - so it should break in gear, not in neutral. Even if it does it'd be pretty easy to take the shift mechanism cover off and manually shift it into gear and lock it there.

IHMO, the USG box is much less likely to strand you and a much stronger design.
I firmly agree with you about it being a stronger design and less likely to strand you; that's one of the reasons why I went that route. That's the first I've heard about the shift motor being a starter motor...that should theoretically mean that it can be rebuilt by someone who knows what they're doing. Let's hope it's a long time before I have that problem...
 

jaluhn83

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I'm pretty sure it is, or at least the guts are. Not sure where I heard that though. Either way, I'd be very surprised if it couldn't be rebuilt by a good starter shop.

The USG is pretty much an off the shelf design, just a custom case and assembly. Why reinvent the wheel? I seem to recall that even the sycros are identical to some common GM transmission.

It's amazing how common some of these parts actually are - basic industrial parts are the same. The hard part is figuring out how to cross reference. Case in point, the valve spool seals for my backhoe are $12 ea through the dealer, but if you measure them they're standard size quad rings that are something like $0.50 ea from a bulk supplier.

One of these days I'll get around to putting my USG box on.... just got to do some fab work first and pony up a few hundred bucks for the custom adapter shaft I need.
 
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