Re-Gearing A Subaru CVT's Final Drive? TR690 / TR580 Teardown For Ring And Pinion- Final Drive

I bought a CVT with the wring final drive, it has a 3.9 and I needed a 3.7.
Sad day. No one seems to dive into these transmissions, so here we go!
They are both TR690's, I failed to think there could be a ratio difference between the Legacys, and the Outbacks, Whoops!
As every Subaru past 2012 has a CVT, it's time to get familiar, and see why no one touches them.
Are they really that complicated? Lets find out!
The idea is to harvest the good 3.7 Ring and Pinion and swap it into the replacement cvt....
Yikes.....

[@garretttucker5838]

To my understanding, subaru people say you can put the outback transmission in a legacy and vis versa as long as you swap both the trans and rear diff at the same time. That way they both have the same gear ratios.

[@steinfabgarage]

I thought about grabbing the rear diff and doing that, but I saw conflicting info about the BIU/ BCM knowing the ratios were off

[@maxeisenhardt4466]

Could just matched the rear diff

[@raystanton238]

When Subaru first came to the USA, their slogan was "Subaru car of tomorrow". But pronounce Subaru the same as tomorrow so that it rymes then it sounds good.

[@christophrichter8234]

"SoBorrow?"

[@yepnotmynamem5157]

im in the reverse situation I bought a 3.7 ratio pinion and I need a 3.9.. wanna trade ? lol

[@steinfabgarage]

Transmissions, or ring an pinions? 😂

[@steinfabgarage]

If only r&p, yes. I’m not shipping a transmission

[@tomdave42]

You definitely are not a mechanic, using strip bolt removal tools to remove a bolt that's not stripped out is hack.

[@steinfabgarage]

I’m sure your more qualified than me