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2013 OB 2.5i 6MT
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Hi everyone. I'm a new outback owner. Bought the 2.5i 6spd. I've perused most of the topics on the gen 4 board and deep-dived into some. I've also tried the search function. I've seen incomplete discussions and opinions on the awd system as it pertains to the 2.5 vs 3.6. Additionally there is absolutely nothing on the 2.5 mt vs the 2.5 cvt. If I've blatantly missed the thread on this please forgive me and point me in the right direction. If not, I'd like to hear from some experts that know from a manual or spec sheet what the real deal is...

Power distribution split. LSD. Auto vs CVT vs 6spd vs Engine size...

Anyone else confused? Thanks for humoring me. The car has been a absolutely awesome. Took it around Kansas City during our snow storm the other day and it was amazing.
 

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Outback Executive 3.0 MY08 (VTD/VDC/LSD)
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915 Posts
(...) Additionally there is absolutely nothing on the 2.5 mt vs the 2.5 cvt. If I've blatantly missed the thread on this please forgive me and point me in the right direction. If not, I'd like to hear from some experts that know from a manual or spec sheet what the real deal is...

Power distribution split. LSD. Auto vs CVT vs 6spd vs Engine size...(...)
Nominal power distribution is 50:50. The car has a center differential. Under power the distribution is permanentely variing, as the open center differential sends power to where it has the least resistance. If there is too much wheelslip on an wheel/axle, the viscous coupling in the center differential heats up due to different speed of the drive shafts and begins to "lock" them together. Fully locked would be a "differential lock". The looking degree on the viscous coupling is not 100 % and lower than the 2.5 CVT and the 3.6 VTD and not always predictable as it is a purely mechanical system which reacts to the wheelspinn. In addition the system has like the other system VDC, which ist electronic stability programm, trottle control, traction control etc. VDC emulates difflocks on the axles, as it breaks slipping wheels down.
 

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Lawn ornament XT
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As a rule, Subaru MTs are all mechanical AWD, and automatics have an electronic system to manage AWD. There are some exceptions but they don't apply to modern outbacks.

Subaru markets these systems as transparently equivalent to each other. They obviously aren't, but they do have remarkably similar performance characteristics in the real world.

The differences always seem to come out in repair costs, never in who got stuck on the trail.
 

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AFAIK the Gen4 OB does not have a LSD but rather uses it's traction control to function similar to an LSD under conditions of slipping. This of course does nothing to improve dry surface handling.
 

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AFAIK the Gen4 OB does not have a LSD but rather uses it's traction control to function similar to an LSD under conditions of slipping. This of course does nothing to improve dry surface handling.
Sort of like color TV's you don't see todays TV's being advertised as Color TV's. I think Looby coined that comparison.

Subaru marketed VDC a number of years ago on its upper trim models given most cars at the time didn't have anything like it.

Today all of Subarus cars have various systems that all perform certain tasks that provide the same type of performance as VDC did back in the day. Which is why Subaru really doesn't say anything about it in their marketing materials.

Regardless of which Subaru Model you look at they all have their various systems set up to provide two types of active traction management. #1 ABS, Electronic Throttle system more or less act as a traction monitoring system and do things to help reduce the chances of the car skidding out of control when your driving down the highway etc. Traction loss is detected by the speed sensors in the ABS system - the ECU is told to back off the throttle to try and avoid causing more wheel spin and traction loss. This is the basics of what the industry calls ESC which is a computer driven response to help retain traction and keep the car safe and even right side up etc.

Then there is the added capability if you have a smart system ABS that can tell when your stuck ie not moving and the car is working to find traction the brakes can be modulated at the wheels that are spinning with no traction and by doing this power is being driven to other wheels that may have more traction. Very cool feature for off road - off camber type terrain where you could end up with two wheels not even touching the ground. The only way to get power to the other two wheels in this type of situation is to have a fully locking diff system which is only found in some of the most hard core 4x4 trucks locking left side to right side so they spin at the same rate regardless of traction. OR you have a smart ABS traction system that says HEY brake that spinning wheel lets get power shifted to the other side. This is what Subaru's system has been doing for some time now on all their cars.

The MT cars have fewer bells and whistles regarding active smart stuff happening on power distribution but they still have the smart ABS wheel spin tracking and brake use to help move power to opposite wheels that might have more traction.

Check out this video of the XV on the off camber where wheels are off the ground they spin a little then the ABS brakes the spinning tire pushing power to the other side. This part of the normal electronically managed Traction control system subaru basically puts in all its cars today. It's just software paired up with the ABS system. Smart simple and quite effective for dealing with wacky traction issues that would other wise require lots of expensive and complicated mechanical bits to do the same thing.
 

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2013 3.6R SAP BBP Outback
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A search on this forum for the term "all wheel drive" yielded 500 threads. I suspect there will be something in the 1000s of posts there you could find with some time searching. Here's what's been posted previously about the AWD system differences for the three transmission types in the Gen 4 Outbacks. However, I do not know if there were AWD changes made in the '13 Outbacks with the new CVT.

MODELS WITH THE CVT - ACTIVE ALL-WHEEL DRIVE: An electronically controlled variable transfer clutch distributes power to where traction is needed. Sensors monitor parameters such as wheel slippage, throttle position, and braking to help determine torque distribution and direct it to the wheels with optimum traction. Normally a 90/10 split front to rear torque distribution.

MODELS WITH THE FIVE-SPEED AT – VARIABLE TORQUE DISTRIBUTION ALL-WHEEL DRIVE: As with Active All-Wheel Drive, an electronically controlled variable transfer clutch distributes power, but through a planetary-type center differential. Torque distribution is normally configured at a performance-oriented rear-wheel-biased 45/55 split front to rear. Sensors monitor the same parameters as for Active All-Wheel Drive.

MODELS WITH THE MT – CONTINUOUS ALL-WHEEL DRIVE: A viscous-coupling locking bevel-gear center differential built into the transmission case distributes torque 50:50 front to rear. Slippage at the front or rear wheels causes more power to transfer to the opposite set of wheels.
 

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2019 Bronze Limited
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Sandroad, not to argue with you, but I have read others in these forums say the 90/10 rear/front distribution on the Cvt's is a myth....

I will be the first to admit I don't know, but in the two plus months I have been a member, I have read multiple answers to this same question, and no one can say for sure what is correct for the new CVT.
 

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Lawn ornament XT
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People get waaaay too wrapped up in the 50/50 vs 90/10 thing. Is might start out at 89/11 but guess what happens when wheelspin is detected?

It changes.

When?

Right away. It might take a few tenths of a second, but it changes and keeps changing dynamically.

Most people are 50/50 power-distributed between left and right legs. But what happens when you walk? Power delivery starts shifting. Balance is restored at the next stop. The car is quite similar in this way.
 

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2012 Ouback 2.5 CVT
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^^ exactly.
This 90:10 split should be nuked from this site. lol

I think the FreeSSM thread should be stickied here in the 4thgen forum. I've along with others have proven that the split is constantly changing by the millisecond.

Our OB's equipped with CVT has a torque split that ranges anywhere between 50:50 to 80:20, all happening in the milliseconds up & down as you drive. The TCM monitors throttle and wheel speeds of each wheel, these inputs play a major roll of the split, other inputs are of course relied upon but not as significant as those two.

Even while your sleeping the torque split is changing constantly getting ready for the next day. :p j/k
 

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2019 Jeep Rubicon Unlimited
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^^ exactly.
This 90:10 split should be nuked from this site. lol

I think the FreeSSM thread should be stickied here in the 4thgen forum. I've along with others have proven that the split is constantly changing by the millisecond.

Our OB's equipped with CVT has a torque split that ranges anywhere between 50:50 to 90:20, all happening in the milliseconds up & down as you drive. The TCM monitors throttle and wheel speeds of each wheel, these inputs play a major roll of the split, other inputs are of course relied upon but not as significant as those two.

Even while your sleeping the torque split is changing constantly getting ready for the next day. :p j/k
Overachievers, these Subies...

I don't know (or care) what the torque split in mine is at any given time... but I do know that in soft sand or mud, the car doesn't sit around spinning the front tires, which is what it would do if 90 of the torque was sent there... It goes forward. Which is the important part.
 

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2012 Ouback 2.5 CVT
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Overachievers, these Subies...

I don't know (or care) what the torque split in mine is at any given time... but I do know that in soft sand or mud, the car doesn't sit around spinning the front tires, which is what it would do if 90 of the torque was sent there... It goes forward. Which is the important part.
:eek:...
 

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2013 Legacy Lim CVT Car: 2011 OB Prem 6MT Car: 2006 Miata GT 6MT mc: 2003 Honda GL1800A * Reunite Gondwanaland *
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...CVT has a torque split that ranges anywhere between 50:50 to 90:20...
Yep, 90:20 is pretty good, but mine is hot-rodded up to 60:60 ...

...with a 47mm oscillation overthruster,

Looby
 

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2011 Subie 3.6R Limited 2013 Cmax e=nergi PHEV
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Yep, 90:20 is pretty good, but mine is hot-rodded up to 60:60 ...


Looby

Sounds like my monovision numbers for my one good eye after a botched lasix operation.
 
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