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Differential swap? Why Not?

Featured Replies

Hey all,

 

I was out wrenching on the Soobs today, swapping Gl-10 rear trailing arms, sway bar and disc brakes into my GL wagon and I got to thinking. The gear ratio for the differential that came out of the automatic is 3.7:1. The gear ratio in my GL 5-sp is a 3.9:1. Correct me if I'm wrong but wouldn't the lower gear differential be better for off-roading my wagon? Wouldn't I get, especially after I mount my pugs and bigger tires, better torque to compensate for the bigger tire circumference?

 

Please correct me if I'm way off base here.

 

Thanks

Aiden

Canby, OR

Youre right, but you would need to swap the tranny as well so it would match. If you put the 3.9 rear in with a 3.7 tranny, the rear tires would spin slower than the front, and well.... that would be bad... very bad.

 

-Brian

Yeah - unfortunately, the manual soob trannies are pretty much all 3.9. The RX tranny is a 3.7, but it's a full time 4WD

 

GD

Hey - where are you in the willamette valley? I live in West Linn......

 

edit - duh, in your sig it says Canby. hehe - we should hang sometime - that's like 15 minutes from me.

 

GD

Originally posted by GeneralDisorder

The RX tranny is a 3.7, but it's a full time 4WD

 

GD

 

so why wouldn't you want the full time 4wd for off roading, lack of low range or is there something inherently bad about full time?

Just more stuff to break. The FT4WD tranny has an open center diff which transfers power front and rear but to whichever end has the least amount of traction (kinda like your side to side open diff, but front to rear). If it has a locking center diff it will lock to 50/50 front and rear, but why go through the hassle for off-roading? With a standard D/R Tranny, when your in 4WD your garantee'd to have 50/50 front rear no matter what.

 

FT4WD would be better suited for racing when 4WD helps, but you dont need a locked center diff (or dont want one in some cases).

 

-Brian

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