3.9 LSD 3rd member????

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Mar 8, 2008 | 11:33 PM

#51

Icemark

Former Moderator. RIP Icemark.

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From: Rohnert Park CA

Quote:

Originally Posted by Johnny_Chimpo_420

My question is- Would a 91 Auto GTU have an open diff?
I recently bought a 91 GTU parts car, hoping for an LSD for my 87 sport.
Well before I installed this "what i hope is a LSD", I drained and refilled the gear housing of the Auto GTU with Lucas 80-90w gear oil. Hope they oil will be good for drifting...anywho-
After reading many "do I have LSD or open diff?" threads, and the test of "turn one wheel and see what the other wheel does".
This is what I've found.
Well, with the wheels on, only one wheel spins when turned by hand. But with the half-shafts or axles unbolted from the diff, they spin opposite of each other.

So is this an open diff or maybe the off chance of a 3.9???
Ill go spin the wheels to see what ratio it has. just over 4 is the 4.1 right?

Open diff.

and no such thing as a 91 GTU in the states.

Mar 8, 2008 | 11:41 PM

#52

NoMorePoison

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From: Linthicum

icemark any chance you could answer my ? real quick? I searched and Im not seeing anything real conclusive

Mar 8, 2008 | 11:44 PM

#53

Icemark

Former Moderator. RIP Icemark.

Joined: Apr 2001

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From: Rohnert Park CA

Quote:

Originally Posted by NoMorePoison

icemark any chance you could answer my ? real quick? I searched and Im not seeing anything real conclusive

what? If you can use a non turbo 3.9 LSD diff in a 88 vert?

Sure, why wouldn't you be able too? The 88 vert came with a 3.9 rear end

Mar 8, 2008 | 11:50 PM

#54

NoMorePoison

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From: Linthicum

I dunno, just wanted to make sure haha

Thanks a ton for the help, and once I get it installed I will check to make sure its 3.9

Mar 9, 2008 | 09:01 PM

#55

NoMorePoison

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From: Linthicum

well got the lsd in today, and cruising on the freeway at 60 yeilded ~2400 rpms, so Im guessing its 3.9

Mar 9, 2008 | 10:14 PM

#56

SouthSideSlider

whats a Turbo V?

Joined: Nov 2006

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From: Goose Creek, SC

i thought all verts came 4.1 i guess i was wrong why would you want a 3.9 rearend i still have mine from my auto to manual swap but only cause iom waiting on a 4.3 to show up at a good price.