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dream car ponderings and questions


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On a Subaru, both front & rear diffs MUST match. If they do not match, terrible things happen...

 

so, if you want to keep the 4.44 gearing of the auto, then you must find a tranny with the same ratio...

 

if you swap to a tranny with 4.11 gearing, you must swap the rear diff to match it.

 

i understand that aspect. it's no different than any other 4wd

vehicle since the wheels spin at different rates. sorry for the

confusion.

what i was trying to work out in my head with my prior post is how

the suby awd system mechanically differs from the toyota 4wd system that

i'm more familiar with. after some thought, now i see; the (viscous

coupling?) kinda takes place of a transfer case. however, with the suby,

you still have the transmission and two differentials, but the front

diff on the suby is actually mated to the transmission. (obviously,

right? ;)) and, without a transfer case, there are no other gear ratios to factor into the final drive

still..., the higher the diff number the lower the gear ratio = larger tire

 

and, so....if i were able to and did swap using my current legacy 5spd

transmission (and 4.11 diff) into an auto foz, would the rear diff from

my legacy mate to it? otoh, (just exploring the ideas here) couldn't i

just regear the front diff on my transmission to match the foz? or more

feasible to just get the turbo tranny to match? i'm asking because i've

got a friend who could actually help change out a diff. it'd save some

money were it even worth the trouble considering the cable driven clutch

issue...which i'm actually still gonna look into

i don't know. i could sell my legacy at the point a foz comes along

and recoup some expense. just don't know how much i'd get for a rusty

body though the rest of it is running very well....save a couple minor

details that i'm finally able to address today

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I'll blow your mind, just because I can.

 

Subarus have center differentials which are normally 1:1 ratio.. USDM 5spd WRX are 1.1:1 ratio, so the front and rear differential rations do not match and it changes the balance.

 

Mind blown?

 

You can change a rear diff pretty easy and they all fit, but the flange changed in the late 1990's so if your trans is a 3.90 gear you might be hard pressed to find one that will work.. However a 4.44 JDM trans uses the same diff as an Auto Forester.

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i suppose my mind would be, except i don't really understand the technical ramifications of that. it's something i'm gonna read up on, though....so i can understand it

well, i'll just keep it simple with the jdm trans if i have to go that route.....a manual/ at swap and all

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