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2004 Outback 2.5L
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Discussion Starter #1
hey guys,

i checked the FAQ's but didn't see any talk of my question which is...what is AWD? Does it mean that all wheels are constantly being driven all the time -like 4WD? If so, is there a ratio or does it change based on slippage. I just bought a used 2004 Outback, but i did take a 2005 WRX out for a spin and noticed that when shifting into second it was the front wheels that chirped and pulled the most torque. I'm assuming all Subie's AWD are the same. Any clarification would help.

best, paul.
 

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Formerly 04 Outback 3.0R VDC, now 2011 Mitsubishi Pajero GLS DiD
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AWD is All Wheel Drive, all wheels driven at all times. It's way more sophisticated than 4WD with all four wheels just locked together being driven in unison. Subaru has at least 3 variaties of AWD, straight viscous limited slip differential used on base manual version which is usually 50:50 front to rear torque split. Then there's ATS All-Wheel Drive which is used in Auto transmission vehicles and uses a computer to transfer the torque away from wheels that slip to one with more traction, this operates 90% Front torque bias until slip is detected. Then there's VTD AWD which is more sophisticated again and transfers 45:55 F:R torque normally for a sportier driving feel.

That's my rather basic view of it, I'm sure others can explain it better.
 

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MY2016 Outback Premium
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AWD basically means that the engine has the ability to deliver torque to anyone of the tires depending on the circumstances. A front or rear wheel drive car has the ability to turn just the 2 tires (one at a time) connected to the transmission and thru the diff open or limited. On a 2wd car if you go through a corner the diff works the inside wheel. If you turn corners back to back then the diff switches back and forth from inside to inside. This is the same for Subie's AWD except both end of the car are receiving power. In reality a AWD system spins 2 wheels (one front, one back) at the same time. Now if slippage occurs then the center diff and LSD goes into action accordingly. So I think you may be thinking the opposite way in that all wheels receive power all the time then slippage occurs for turns. HTH
 

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Formerly 04 Outback 3.0R VDC, now 2011 Mitsubishi Pajero GLS DiD
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Cannonball said:
This is the same for Subie's AWD except both end of the car are receiving power. In reality a AWD system spins 2 wheels (one front, one back) at the same time. Now if slippage occurs then the center diff and LSD goes into action accordingly. So I think you may be thinking the opposite way in that all wheels receive power all the time then slippage occurs for turns. HTH
I'm confused by your wording "spins two wheels (one front, one back) at the same time" are you meaning in hard cornering? On most Subaru's all wheels do receive power at all times, then if slippage occurs power is reduce to the slipping wheel and diverted to the non slipping wheels.
 

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MY04(SE) Outback 2.5 i, MT i.e bog standard
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Jondalar said:


I'm confused by your wording "spins two wheels (one front, one back) at the same time" are you meaning in hard cornering? On most Subaru's all wheels do receive power at all times, then if slippage occurs power is reduce to the slipping wheel and diverted to the non slipping wheels.
This would be true for a car with only a centre limited slip differential(lsd) and or torque/power distr. device. The standard legacy for example has no rear lsd and in the US some MY Outbacks lack a rear lsd. In this case you could potentially be stuck with two spinning wheels, one front and one rear. With a rear lsd you would have at least three wheels turning over. One would assume that "spins two wheels" means stuck with two wheels spinning?
But as I belive all new Outbacks now have a rear lsd this really could'n't happen without shearing the very same lsd.
 

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2001 Wintergreen Outback 5MT
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My 98 has no LSD, but then, I've never been stuck with two wheels spinning. I should try to find a place to test that this winter.

I have driven tractors on ice (when plowing snow) and it can be fun to play with the split brake pedal - if one wheel spins while the other one sits on dry pavement, then lock the spinning wheel with the brake, and the tractor moves.
 

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I got stuck with mine 98 OB! AWD is same as 4x4 just with independent suspension!
When tranny in AWD mode 50/50 front and rear receive same power but since it has open differentials only one wheel per axle turns, usually the one that is easier to turn!
From my point of view it would be wrong to call it an AWD system, since u never get all 4 tires to spin at same moment, i would rather call it AWD when it would have differental locks on it and it would be the diff lock when u van say all 4 tires turn at same moment!
 

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I got stuck with mine 98 OB! AWD is same as 4x4 just with independent suspension!
When tranny in AWD mode 50/50 front and rear receive same power but since it has open differentials only one wheel per axle turns, usually the one that is easier to turn!
From my point of view it would be wrong to call it an AWD system, since u never get all 4 tires to spin at same moment, i would rather call it AWD when it would have differental locks on it and it would be the diff lock when u van say all 4 tires turn at same moment!
Ed locking diff systems are called AWD by the way. My Land Cruiser had center locking diff and front locking diff - and is full time AWD. It also has a very heavy complicated center gear box to enable this feature. It also sold new in 1993 for $52,000! The locking diff systems at this level have a whole different intent and purpose beyond your standard intended application of a car based subaru. Even with this KING of 4x4's Land Cruiser there are very rare occasions I have actually needed and used the full locking and crawling gear capability of the land cruiser. Which is why 99.9% of the new suv's sold in the US do not have proper locking diffs or even a center gear box for crawling ability given so few people will ever actually have a need for it.
 

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I know exactly what ur saying about a land cruiser!
But its embarassing that a GUY in a SUBARU gets stuck on a PARKING LOT wich was my case!

Do u still own this toyota?
 

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@#it, i thought they did around 16mpg hwy on gas engines and 23-24 on diesels!?
Im looking at them right now, since diesels are in RHD only and parts hard to get im thinkin about an gas model 7 seat with diff lock option!
U said 99% of suv are without diff locks, which suv would make up the other 1%?
 

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@#it, i thought they did around 16mpg hwy on gas engines and 23-24 on diesels!?
Im looking at them right now, since diesels are in RHD only and parts hard to get im thinkin about an gas model 7 seat with diff lock option!
U said 99% of suv are without diff locks, which suv would make up the other 1%?
The 4.6L strait six engine is basically a tractor engine that was in the 80 series LC. The 99's and newer run a 4.7L V8 based on a GM design also a different and less durable transmission. People who bought the old 4.6L strait six and drove them flat out 80mph on the highway like a V8 Suburban usually blow the head gasket on the strait six given the six isn't designed to be used that way. That old 4.6L is designed to run for 300+,000 miles at slower speeds and harsh conditions. Occasionally I might do 70mph down the highway in my old LC and it does that just fine - but I have no illusions of blasting over mountains at 70+ with the old 4.6 strait six.

The old gas 4.6 strait six gets between 12-14mpg depending on which way the wind is blowing. In comparison the Ford Bronco in 1993 posted 8-10mpg with its V8. So when your comparing roughly the same sort of era and vehicles the old LC got some impressive mileage for 217hp full time AWD. The newer 100 series which marks the end of the real Land Cruisers in the US given the US 100 series runs the same gear as all the other toyota's your just paying a pile of cash more for the LC name plate.

Over seas the strait 6 turbo diesel LC does get 24-25mpg with the right driver. Our 9 passenger brand new LC which is a stock slab sided LC built in Japan shipped to Tanzania then stretched to seat 9 posted 25mpg US. Our driver said the toyota 6 TD was considered the cleanest running of the TD's used in the Serengetti. However when he does research trips during the winter he runs their LandRover because it weighs less and is far superior in the mud than the heavy LC's but the engines in those are very dirty and very low tech and not as reliable.

My guess is that a 2003-2006ish Toyota Sequoia Limited will end up replacing my much loved LC. Makes no sense to get the newer 99 and up LC's given they are running the same gear as the Lexus GX and the Sequoia which are far cheaper and easier to find. Which those two get in the 12-18mpg range for the most part. So you don't upgrade for the mileage but you do upgrade for the enhanced ie smoother ride and safety systems to make the wife happy.

Also the 4.7v8 powered toyota trucks can also be driven like the Suburban - flat out 80+ down the highway without blowing a HG. LOL
 

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I test drove a 2011 WRX a couple months ago and grabbed 3rd gear and all 4 wheels chirped !
Took a few weeks to get over that Test ride and truthfully I aint over it yet. Sweet Sweet Ride.
 

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i used to live overseas and all we had were diesels suv but in LHD, like the Mitsubishi Pajero, Land Cruiser, Lada Niva all these suv were common, we sometimes seen the Land Rover and Mercedes G class but these were expensive and hard to get parts!!
what would u say, as of right now from year 2000 till now are there any suv available with front and rear diff locks?
 

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i used to live overseas and all we had were diesels suv but in LHD, like the Mitsubishi Pajero, Land Cruiser, Lada Niva all these suv were common, we sometimes seen the Land Rover and Mercedes G class but these were expensive and hard to get parts!!
what would u say, as of right now from year 2000 till now are there any suv available with front and rear diff locks?
LC has the diff lock - though the Lexus GX is essentially the same machine and there are more to choose from and often far cheaper. The Toyota FJ has diff locks and certain 4runners will have them. Nissan's in rare cases can be found with them most don't.

A good friend actually runs a business specializing in G-wagons in the US. LOL - he's the one who told me to get the 93 LC.

You can always custom build ie add diff locks to just about any SUV with a fairly standard 4x4 system with the transfer case.

The best bang for the buck in the US is probably the Lexus GX 470 lots of them out there all dealer maintained and owned by older folks who used them to make trips to the grocery store. The only gotcha the 4.7L v8 is a timing belt and has a large timing belt service around 90-100K done right it includes all the idler bearings tensioners and water pump. Dealer cost runs into the $2000+ range. I've been eyeing them as a replacement for the LC but its no where near the same 4x4 vehicle the old 80 series is.
 

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This might help a little with understanding AWD. It looks like a rather simplistic explanation, but it seems that's all you are looking for.

All-Wheel Drive | Subaru AWD

As mentioned Subaru has tweaked their AWD over the years and different transmission/engine combos will result in different specific qualities of AWD. AWD is not the same as 4x4. AWD has full access to power all wheels without driver input. 4WD requires activation of 4WD, and is a "dumb" system simply applying power to the non-driven axle.

Also, one important thing to remember, All Wheel Drives are not all created equal. There are many variations, most deriving from a modified 4WD drivetrain. Subaru's biggest advantage is that it is a true AWD platform from the ground up, general resulting in better, more intelligent application of force to all 4 wheels.

As mentioned, AWD will not get you out of all situations, you can easily get hung up with an AWD, but it is far superior for driving in poor on road conditions such as heavy rain, snow, slush etc. Needing something to crawl over rocks and through deep muck will not meet the same needs for on road driving, you can have a vechicle with locking difs, big tires on a 4WD drivetrain and when you hit a hard turn at 50mph on wet roads, the back end will kick out on you. In a Subaru it will hug the road and keep going.
 
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