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Understanding Dual-Range 4WD

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Okay, I'm hoping this isn't a dumb question, but after searching I'm still not 100% certain as to the answer.

 

What I basically want to know is this: on an EA81 vehicle with a dual-range transfer case, are the 4WD modes true 4WD or AWD? That is, is there a centre diff, clutch, or other arrangement allowing for slip between the front and rear axles? From what I've read they appear to be 4WD as opposed to AWD, but I'm still not entirely sure and my nine-year-old memories of my past Brat are pretty flaky at best.

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all ea81s with 4x are a true 4x4 4wd system. when its in two wheel drive mode, all you are turning is one wheel in the front. when you switch it over to 4 wheel drive it sends power out of the rear of the tranny to the rear diff, which spins one rear wheel.

 

so its strictly 4wd, and not awd.

 

some of the newer subarus, mid 80s, ea82s. had a viscous center diff. and these were all wheel drive.

 

the xt6s had a locking center diff, so they were all wheel drive, and 4wheel drive.

 

but brats are 4x only.

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the xt6s had a locking center diff, so they were all wheel drive, and 4wheel drive.

 

but brats are 4x only.

 

Thanks, this is what I wanted to know :)

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"wrong archie, no EA82 had a "viscous center diff" they had open centers with a locker. like the XT6"

 

Hmmmm? My understanding is that the EA82's (at least the dual range ones) had no center differential at all -- just like the EA81's. You can demonstrate the 4WD vs AWD by turning sharply on gravel with it in 4WD/AWD position. If it's got 4WD, or a locked center differential, it will skid at least one wheel.

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on an ea82 dual range 4wd trans it is locked if you have it in 4wd and turn sharp on pavement the car will lock up and will hardly move unless you have some loose gravel, sand or dirt on it so the tires will loose traction and slip. plus if it locked on a sharp turn like that just try and take it out of 4wd, good luck with that. don't know about the push button 4wd, just dual range manuel shift. i have been there and tried that.

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plus if it locked on a sharp turn like that just try and take it out of 4wd, good luck with that

 

Yeah, forgot that part... It does bind pretty well.

 

I still like the dual range 4WD better than the AWD of the newer ones -- when you are plowing uphill through deep snow, you need to keep the engine RPM's up, and that lowest gear really helps. My dad's '96 Outback will stall the engine in deep snow before the wheels start slipping. Although I suppose that could also be due to the traction control keeping power to all four wheels instead of just two.

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I was refering to the fulltime boxes, the regular 5spd D/R is just like the 4spd D/R of the gen 2s

 

I perfer the "RX" boxes (the 87 and later fulltime D/R with the lockable center diff)

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I perfer the "RX" boxes (the 87 and later fulltime D/R with the lockable center diff)

 

You know, I've never seen one of those. There's a gazillon of the EA82 wagons around here (and a lot of the EA81's as well), but none of the ones I've seen have the locking center. Do you know how many of the RX versions were made compared to the standard?

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the RX is a relatively rare car, but there should be a few in colorado, more there than in Michigan, but i've not seen any here, so i guess that's not saying much. the low range on those trannys is less than the NA DR, 1.19 as opposed to 1.52, so if you're pushing big tires its not a good idea, unless you swap the low ranges, but you still have the 3.7, which is still not so good, unless you do a lot of highway.

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the RX is a relatively rare car, but there should be a few in colorado, more there than in Michigan, but i've not seen any here, so i guess that's not saying much. the low range on those trannys is less than the NA DR, 1.19 as opposed to 1.52, so if you're pushing big tires its not a good idea, unless you swap the low ranges, but you still have the 3.7, which is still not so good, unless you do a lot of highway.

 

Hmmm. So the RX tranmission is what was used with the turbo engine? Which there are some around there, but not many, and I've never driven one so I didn't know the trannies were different too. Guess I need to learn my subaru history better. :)

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the RX's are verry rare. up here in canada i heard that the dealerships only had access to ONE car.

 

I love the D/R trannys in the RX i put it in low for auto-x's/rally-x's and high for dailly driver (or viceversa can't remember)

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