Selectable 4wd

Flywheel, Clutch, Transmission, Axles, etc...

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josh2109
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Joined: Wed Jun 08, 2016 9:52 am

Selectable 4wd

Post by josh2109 »

Hi folks,

Just a quick one - my Legacy has the selectable 2wd/4wd manual gearbox with high and low ratio.

My question is, having owned a couple of different Japanese 4x4's I'm used to not being able to use 4wd on tarmac due to the lack of a central diff causing the transmission to wind up... Is the Legacy the same, or am I ok to drive it on the road in high ratio 4wd mode?

Cheers,
Josh
Alphius
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Joined: Mon Aug 31, 2009 9:09 pm
Location: Rochester, WA

Re: Selectable 4wd

Post by Alphius »

Here in the US the Loyale/Leone cars have the dual range, but it has three positions: 2wd/4wd-hi/4wd-lo. On ours, the center diff is open in 2wd and locked in 4wd positions so you cannot drive it on dry pavement in 4wd.

I am also aware of other market transmissions connected to EJ engines in Foresters and Outbacks that have a viscous center diff with two positions: lo and hi. On these, there is a standard viscous center diff so it is not harmful to drive in either position as the AWD is always active. Here's a picture of the sticker for that one:
http://i.imgur.com/LVJ66oa.jpg

Which type do you have?
A quick way to test is to put it in 4wd in a parking lot and try to turn slowly at full lock. If the drivetrain feels like it binds up, don't use it on pavement. If it doesn't bind up, you're good and likely have a viscous center diff active in 4wd.
josh2109
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Re: Selectable 4wd

Post by josh2109 »

On mine the 2wd/4wd changeover is operated by a button on the gear stick. hi/lo ratio is switched between using a lever behind the gear stick.

Image

When the car was delivered I tested 4wd in the yard outside the barn (it isn't paved, it's a mixture of compacted dirt and gravel) and when turning at full lock you can feel feel that it binds in exactly the same way as my trucks... So I'm guessing that 4wd is for loose surfaces and slippery roads only.
Alphius
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Location: Rochester, WA

Re: Selectable 4wd

Post by Alphius »

Yes, sounds like you're correct. 4wd is for loose surfaces only. The next question that I'd be interested in finding out is whether the car has AWD with an open center diff or FWD when the 4wd button isn't pushed. That's a very interesting setup that we didn't get over here.

In the early 90's, Subaru of America was trying to distance itself from the "farmer car" stereotype that the L-series cars before it had, so they kept the vehicle content high and simple. All these complicated levers and 4wd buttons and such just don't convey the pseudo-luxury image SoA was attempting to portray. We just got simple, easy fulltime AWD. Every Legacy had the single-cam fuel injected EJ22. Almost all had power windows, power door locks, power mirrors, tach, etc. to the point where seeing a first-year only Legacy with manual windows is like finding hen's teeth; I've seen one in person over 10 years.
josh2109
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Posts: 23
Joined: Wed Jun 08, 2016 9:52 am

Re: Selectable 4wd

Post by josh2109 »

I can answer your first question, as the first question in my head when I put it in to 2wd was which end does it drive from... Dumping the clutch and hitting the throttle hard revealed that it runs as a FWD car in 2wd mode - I was really hoping it would drive from the rear end, but I can understand why Subaru chose to go FWD as it caters more for your average driver. When you engage 4wd you hear a vacuum solenoid engaging in the rear of the gearbox, presumably this makes and breaks the connection to the rear axle.

We had a similar thing with most Japanese manufacturers in the UK, in the 70's there was a bit of snobbery towards the Japanese marques and so from the 80's onwards the Japanese manufacturers chucked power windows, mirrors, sunroofs, a/c and anything else deemed 'luxury' into their cars as standard in an attempt to change people's opinions. People in the UK still drive European rubbish though, you can't move for Volkswagens and Vauxhalls over here. My ex girlfriend's brother bought a brand new Ford Fiesta recently, and I was amazed that it was more poorly equipped than my '87 Honda Accord.

I shouldn't complain, the stubbornness of consumers over here means that Japanese cars are an absolute bargain, and you get to be smug when all your mates are complaining about the reliability of their Euro junk whilst your 25 year old car still runs sweet as a nut lol.
Alphius
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Joined: Mon Aug 31, 2009 9:09 pm
Location: Rochester, WA

Re: Selectable 4wd

Post by Alphius »

Yeah, I think a lot of it had to do with the very strong yen and booming Japanese economy during the 80's and early 90's. It simply was cheap for them to develop and build crazy cars and remain competitive on price, like the LS400, 3000GT VR4, Supra, turbo everything, etc...

There's no contest on reliability when it comes to older Japanese vs. Euro cars, that's for sure. :lol:
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