W5M31 Question

[Ruben16V]

Well, a guy is selling me a gearbox out of a Galant AWD and he has told me it must fit my 2G.
I have read a lot of things, such as this must have a switcheable center diff. But nothing really makes sense

Gearbox is W5M31-2-VQXK, so it came out of a NA Galant AWD.
My problem is I have a 2G LSD rear diff, and have no idea if I can just install this with no problems because of gear ratios, or even if the case would fit my roll stops, but that´s nothing cause I can ask for a picture of the case, so please ¨gearboxes gurus¨ bring me the light.

The other question I have is, as long as it came off of a NA car this gearbox is weaker than our W5M33??

 

[bastarddsm]

It's rated for like 228ft*lbs, and a 33 is good for 240 I think. I do believe that the 31 could have longer fatigue life than a 33 due to the fact that they drive off of 4th gear instead of 3rd. They do have ball bearings on the input shaft so I'm not sure how they will handle the thrust loading.

They do have a 2.81:1 final drive. You would need to either sway in your final drive from the 33 into the 31, but then you would have an extremely low geared box. Or you could put the 2.81 GGSX gear in your rear end.

 

[Ruben16V]

OK, so it sound like i have to find another gearbox.
Any recomendation?? because I supose a EVO III is the strongest gearbox but is almost imposible to find, and don´t want to be scamed

 

[bastarddsm]

I really don't beleive that an EvoIII is any stronger than a normal one. The 3/4 gears are 1 tooth less than dsm, so they have increased clearance, which leads to heavier tip loading. Plus with the missing tooth the load per cycle goes up so the fatigue life goes down.

That is unless they use a modified pitch circle to increase the tooth thickness, but I don't think so because you can't do that unless you do it to both gears.

 

[pauleyman]

That is unless they use a modified pitch circle to increase the tooth thickness, but I don't think so because you can't do that unless you do it to both gears.

If the ratio changes both gears must be changed. In a fixed distance system this must be true. if there were a chain between gears like a bike that's diffrent

 

[bastarddsm]

You'd think that but the mitsu system doesn't the Evo uses the same intermediate shaft as the Dsm, and the Evo gears have 1 less tooth.

 

[donniekak]

If it's from an early 90's galant gsx it won't mount in your car. They have the same single mount point as a 1g dsm trans, and no front, and rear mount like a 2g.