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Funky gear ratio question

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I've been wanting to know this for some time, but not sure how to come up with an answer.

 

My wagon has an RX 3:7 dual range full time tranny in it. However, its been dropped to 4:11 to match up with the 4:11 LSD I have. So.....what ratio would that put the RX 1st gear into when in Low range? --E

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me too......your tranny has the lower numerical front diff. you need to swap the 4.11 LSD unit inside the pumpkin, into your RX rearend ring gear, the big one, there is a write up on how to do this, follow it to the "T" and you should be fine, and if not ask here.

 

 

 

 

~Josh~

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I've been driving on this setup for the last 7 years, but I've never known exactly "how" low the 1st gear is with this configuration. --E

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1st gear = 3.545 i think.

You need 1st gear x low ratio x final drive

so you have 3.545 x 1.196 x 4.11 = 17.425 overall ratio.

 

Maybe... a thought for those who want a 4.11 final drive, perhaps the FULLTIME 4wd RX box, like this man has is the same setup as the later RS legacy trans(also fulltime 4wd but with the lsd centre). If so, you can use the pinion shaft and crownwheel out of the ej20 box and slot them into the ea82 box, since the pinion is on the end of a longer shaft with splines for the centre diff.

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How did you verify your rear diff is 4:11....?

 

the diff sticker may not be true if your Mech.....was swapping things......What really needs to be done is a Spin test in the rear....to verify 3:70 or 4: 11 gear set.....

 

Or pull the rear and physically count teeth.....

 

I have been Researching this 4:11 gear swap into a Hi-Lo Box for Several yrs now.......I wish you were closer I'd Love to look at the work done to your Ride....

 

let us Know, John

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John,

 

You'd be a hero if you could figure out how it's done! :headbang:

 

Go John Go!

Glenn,

82 SubaruHummer--needs lower gears.

01 Forester--needs D/R

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Ive seen the car and rode in it with lo range engaged and its definately crawling slower than the 3.7's I have rode in. Im going to be looking into trying to do the same thing in the near future for my car if it works Ill share.

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