How to make a Subaru 4wd on demand

In this video I show you step by step how to make your Subaru an AWD beast. This mod will lock your center diff so you can go off road with ease. Big thanks to the guys at subaruforester.org for helping out with this modification.
As I state in the video, this ONLY works for the 4eat transmissions.
I changed the link to the resistor, anything 2.5 to 4ohm and above 15w is good to use
Here is the switch I used: amzn.to/3ija4B2
Here is the black switch: amzn.to/2GDyOGe
Here is the resistor: amzn.to/3spg7bD
Wire strippers: amzn.to/3e5lCHd
Wire: amzn.to/3m5qBLp
Support the channel through my Patreon: / jrobling
Check out Merch on Amazon: www.amazon.com...
or Teespring: teespring.com/...
Follow me on Twitter, Instagram, and Facebook
/ mrrobling
/ mrrobling
/ mrrobling
Check out every product that I review or I recommend in my videos here on amazon: www.amazon.com...
My Gear:
Camera: amzn.to/36jsHBz
Phone: amzn.to/3oN0soe
Lens: amzn.to/3fXb9hT
Light kit: amzn.to/33q4zv4
LED lights: amzn.to/37kHsTV
Sound proofing: amzn.to/36eXvmK
Tripod: amzn.to/2J9txIp
Mini Tripod: amzn.to/3mjlSWa
Shotgun Mic: amzn.to/3qbL0jJ
Lav mic: amzn.to/3qbOB1

[@elsydeon666]

I would probably use crimp spade terminals for the wires going to the switch. This lets you rewire if you get the connections wrong, makes the connections easier, and makes it easier to replace the switch.

[@ace7912]

yes and a ring connector going to that ground above the fuse panel

[@johngifford7725]

Carling makes that switch with a 12v powered illumination. Thanks for making this video. I'm almost at the end, and I hope you explain the technical aspect of this for those of us who can understand it. I'll check your channel out to see more. Great video.

[@silentthunderbird3390]

this is genius idea and subaru should add that feature to their system

[@r.j.bedore9884]

It was a pretty decent explanation of this mod, however you misspoke a bit in your initial description of the AWD system. Some older Subarus had a viscous coupling in the rear differential and all non-STi AWD manual transmission models have one in the center differential, but none of the automatic transmission models have a viscous center differential. The automatic transmissions use a multi-plate clutch pack to shift power front to back. The standard models have something like a 90/10 front to rear nominal torque split, with up to 50 percent of the power being sent to the back if the wheel speed sensors detect slipping at the front wheels. The automatics with the VTD system have a more performance oriented 45/55 front to rear nominal torque split and are capable of shifting more power back and forth as you accelerate and brake, as well as when the wheel speed sensors detect slipping. Basically this mod has you activating the clutch pack from the more common 90/10 system so that it sends as much power to the back as it can by locking that clutch pack together to give you a 50/50 torque split. While it has the same net effect, it is not the same as a true locking center differential as it relies on the friction of the clutch pack rather than actually mechanically locking the front and rear output shafts together. As such, the performance of this "locker" is entirely dependent on the health of that clutch pack and how well you maintain your automatic transmission. That said, it can be a useful mod in situations where you know you are going to have wheel spin since you can "lock" the center without having to wait for the front wheels to slip. Some people have done similar things in the past to completely disengage that clutch pack to make their Subarus FWD in an attempt to get better fuel efficiency. I personally saw this on an SVX once that I was considering buying, but changed my mind when the switch broke during the test drive.

[@simr2105]

Thanks for pointing this out regarding automatics and their MPT clutch versus manuals with their viscous limited slip centre diff - I was about to do the same and you explained it well!

[@matusg914]

Older models (BH) with VTD had center differential coupled with a clutch pack, but I don't think any outback had locking or LSD rear diff

[@r.j.bedore9884]

@@matusg914 I don't know about the Outback, but some 90's era Legacy's and early 2000's era Forester XT models came with a speed-sensing viscous coupling type rear LSD, as did most WRX models. The STi (and I think some limited edition WRX models) came with a mechanical torque-sensing rear LSD (like the Torsen differential).

[@TheW0rldisMine-b2l]

@@matusg914 B12 model H3 is with VTD and rear LSD diff :)

[@TheW0rldisMine-b2l]

It’s a well spread lie about 90:10 front to rear, but is actually pro-active AWD and is engaging differently every single second. 90 to 10 ratio is in IDEAL conditions, for example you are cruising on the highway in nice weather middle of July, speed locked on 75mph with cruise control in straight line, in that case is 90to10, but the very next moment you swirl the steering wheel to overtake someone, your car is already changing the proportions of power distribution.

[@countryguywithcamera]

Go to a junkyard, and nab one of those factory fog light buttons and do the same

[@PIX3LRAC3R]

Great video! I had heard about this mod, so happy that I found your video showing how to do it. Can't wait to do it on my lifted '03 SG Forester.

[@tegridyfarms5251]

I did this on my 06 outback, had to make some modifications but the test matched up to yours. Great video.

[@mattwellstead7468]

did you find any long term effects with this mod ?? I'm considering doing the same on my 05 outback after watching this lol

[@ace7912]

17:30 bro that exhaust sounds so good lol

[@elijon8954]

Look into add a circuit for tapping straight into the fuses for power.. they work great for gauges!!! Just rebuilt my top end and put in a new used transmission into a 04fxt with a ej20x mortor swap (that i paid way too much for to begin with) but now trying to make it great looking into this mod and its genius but beleive it can be simplified and perfected a bit with a few mods of its own.... such as the add a circuit and also a dpdt relay so the ligh lights up when the swith is on. Also found some sweet rear diff lock switches with customizable led lights (i went with green but really liked the red/white because when its off the white lettering of the rear diff lock is illuminated but when on it illuminates the red symbol of the differential so its obviouse when its on and you dont accidentally knock it on and not notice... actually i just ordered it on amazon and might change it from green the the white and red... but my favorite color is green UGHGHGGHV😅

[@elijon8954]

Also just saw a comment where if you're in first gear it automatically locks the diff so this isn't needed as much as it seems but after all the research and just ordered sweet switch, dpdt relay, and 14awg wire, I'm still doing it just gotta find the right way so it will still engage with tire slippage if off but will lock when turned on,,, don't want to blow the diff or tran having it on driving in snowy weather faster than it's meant to go with the diff locked but also want that extra safety for when it does slip..... ya know?

[@mauriciobeltran4922]

thank you for this insight,is work good on my Forester 2008 no turbo 👌

[@jackmankins2520]

I love your forester, it looks so nice!!! And this is a really cool feature you’ve set up for your car 😁

[@srboromir452]

Had this on a legacy sedan, we had crazy problem, had to go to two mechanics to figure out two shops ago put different sized tires on the back. Actually improved my mpg to leave the car in FWD, would just put my car in neutral, flip to AWD and i could climb the mountain that was my sister's washed out vertical churt driveway

[@srboromir452]

Okay watching more of your video, I realize you're doing a way different mod than I did. All I did was stick spade connectors and a switch into the fuse that forces fwd

[@Viesiitis]

Take off the orange button cover from the base and put in same size 12v halogen or led bulb. 3-5 mm size bulb fits there.

[@ironman1518.]

Thank you well made presentaion!1 Is the something similar or the CVT transmissions, OR those do NOT need this mod?

[@Subgunman]

That wiring diagram is for a non illuminated switch. One would need an additional one or two additional contacts for the light ( one contact is automatically grounded through the existing contact that would be noted as ground). Any idea if there is power available on one of your contacts when switched on or if there is a contact that grounds when turned on. Either way you could wire an LED indicator and mount it to the blank panel next to the switch or perhaps hide it somewhere up in or on the instrument cluster. This reminds me of the mod I did to enable cruise control on my car. Two contacts are used to the steering column and running through several resistors. The resistors tell the ECU wether to engage or disengage cruise while the other two resistors control increase or decrease speed. One also needs to add the factory switch that enables either cruise control or speed minder as long as the factory harness has the contact assembly clipped behind the switch panel.

[@johnsanpedro6316]

I'm definitely doing this for my trip to the Arctic Circle.

[@hoberspank]

I appreciate this video so much! Have been waiting for a nice easy walk through step by step video for a while now as i wasnt to sure going of paper alone. Cheers!!

[@tonyn1991]

I find it amazing that this video has had over 120,000 views. Years before this video was made, I posted a video of locking the centre diff of the dual range 5 speed Subaru gearbox. I followed it up with the worlds first locking Subaru rear diff with an e-locker that myself and a mate developed. What I know is that while the locking centre diff is a good first step, you really need to go the next step with an e-locker rear diff. As for the e-locker front diff- that’s something I’m keeping to myself.

[@kylefox2341]

Hey man. Just stumbled across this. Good to see you got it working nicely. Will have to link this vid when the next person comes to the forums asking about the centre diff lock👍

[@theMatrixEndsHere]

Hey man. Sounds like you are on a subie forum. I see some people saying don't bother just put the trans in 1 for a locked 50/50 split but does this not allow for 50/50 split into all 4 speeds? (I have a 99 Legacy SUS, 4eat).

[@setoman1]

More recent Subarus come with X-mode, which does the same thing. Sadly, they’re missing the rear LSD, which is not difficult to retrofit, but costs a lot more money.

[@pellcio]

Thanks for this video. It is something I've seen on other Subie vids, but have wondered about how it works and how it's done. You can also "explore" the fuses to see which one only comes on with car running, then get a fuse piggybacker to run your power from. You can do this easily with a test lamp while key is in run position. On a side note, doesn't Subaru sell accessory swithches that you could also use? It would be super clean and fit in the hole seamlessly.

[@mtcondie]

This is great! I am going to do this mod on my Subaru soon.

[@HelmCast]

Subaru Forester 2009? will it work?

[@chucknorrisismyfather]

Thanks for the video! worked great on my xt.

[@shannonharris2816]

Nice job, Charlie

[@CyberPun]

19:36 The most proper way to say "accessable" 👌

[@michaelmyers3892]

I think I would take mine and have an ARB air locker installed in my 2002 outback all-wheel-drive this way I have full control when their rear-ends locked-in or unlocked it won't damage anything electrical or on the transfer case or possibly other important things

[@rustyspace900]

I wonder how all this works with a manual? TCU is with automatics only right?

[@ShanusPortellusVI]

I’m wondering how long that computer module will last with a physical switch flipping current off and on.

[@swedesspeedshop2518]

Why not get power from the fuse panel? It’s right there?

[@porsche558]

Cool modification, if you lock the TCU into staying in that 50-50 mode won’t that cause premature wear on the center diff? I’ve noticed that Subaru has been listening to people like you. Newer cars that feature X-mode essential have something like this and more baked in. Also nice to see a Forester XT, I wish Subaru still made an XT version or at the very least put turbo in the Wilderness edition.

[@imitt12]

It actually causes more wear on the center diff unmodified, because the TCU is only engaging the clutch pack when it detects wheel slippage. That causes a lot of shock loading, which can destroy the clutch pack under heavy use. The idea for the switch is to engage the diff before you go off-roading, so it's not rapidly slamming it together.

[@shaneclack3234]

@@imitt12 would using Xmode in conjunction with this mod be feasible or even possible?

[@artenalata2009]

@@shaneclack3234 AFAIK the Xmode overlap these mod...so it its not really needed. If anybody have more info on it please tell me.

[@shaneclack3234]

@@artenalata2009 I find it interesting how many/few hardcore builders and modders tinker with this platform. I have an extensive background with jeeps and 4x4 trucks, so theres a neverending source of info for this kinda stuff. Wife recently got a Crosstrek so im knee-deep in research trying to make it more offroad capable... Maybe I should start drafting and engineering some mods/features for these things...

[@petercornetet8267]

The way u explain things makes any idiot guy like me think I can do it 😂 awesome video!!

[@jeffarcher400]

Wondering if you could blow a fuse if you try using the lighter while the diff lock is engaged. Also a plug in spotlight could trip it. Cell phone charger probably not. Great mod! Can't wait to try it.

[@summerfox9292]

I thoughty '07 Forester was awd all the time?

[@gendolf1983]

Thanks for sharing! Where can I find the 4ohm 15kW load resistor? Could not find it in Aliexpress or EBay..

[@dylanschmidt4607]

Will you make a video of you using this up hills to see how much of a difference of torque?

[@JohnBrowning-h3g]

Fantastic video… is there an option to do the same for my manual 6 speed transmission turbo diesel SH Forester (UK option) as this would make it unstoppable? Thanks in advance from a UK 🇬🇧 guy

[@merlin2072]

My 2008 outback with 4eat has a different wiring configuration and no white and green wire do you know the correct wire to tap into.

[@hermanyeung4227]

Great video! I have a 2014 Forester 2.5i Premium, will this work on my car? And if so, also change pin #4? Thank you.

[@michaelreed649]

What an awesome video. Thank you for this insight

[@andrewbernier5244]

I tested my pin 4 wire, It seems to be pulse with modulated. And its Yellow / green. So i put the resister to the TCM Pin 4. Then set up Switched 12 Volt to the solenoid ? Do you think this will overheat the solenoid, after a while?

[@shaktishaker]

How can an awd suddenly become 4wd when there is no locking center diff?

[@andrewmena3118]

2016 outback 3.6r……..do it correctly……i bought a TORQ MASTER TORQ LOCK auto lock diff…..done!!!!!!

[@Klaus_liHao]

In 'Transmission Control Module (TCM) I/O Signal' , both of 'Lock-up duty solenoid' or 'Transfer duty solenoid' how to select?

[@DanSlotea]

I thought the "Hold" button on my '06 SG9 2.5 XT does that?

[@SandShark350]

I'm assuming this doesn't work for 2021 Forester with a CVT transmission

[@frfigueroa2002]

Would you do this for us at a cost? For those of us that do not have that me mechanical inclination????

[@LarryRichelli]

Hello, Looking at your hood you subaru is a turbo but you used the non turbo resistor. Also I can't find a 4 Ohm, 15 Watt resistor on amazon.

[@lancetrusty1058]

Do you have a wiring diagram for the mod for a non turbo engine. Thanks

[@GusgusA1]

Please someone tell me why there is a resistor to ground? This i dont understand.

[@jamesg8246]

My 02 Forester S with 4EAT would lock front and rear if you manually selected 1st or 2nd gear without any mods. You really don't need a 50/50 split once you're at 3rd/4th gear speeds. Not sure how this works with a CVT.

[@matteoperron5436]

I'm interesting in this, are you sure it locks the diff also? I thought it only gave you 50/50 split. It would be bad on pavement then if you had it set on 1st gear right?

[@jamesg8246]

@@matteoperron5436 It was just me stopping on a dirt road and nailing the throttle and looking at the ruts dug. In 3rd or 4th/Drive the front tires would dig in and the rears did very little. In 1st or 2nd gears manually selected with the automatic all four tires would dig in.

[@redflames19]

How does this compare to the snow/mud setting in newer Subaru's?

[@AH6man]

Will this affect the normal operation when it’s turned off? Will it never lock the diffs when off and only lock if on?

[@talderi9315]

Looking greeat!! I have a impreza b3 2L but manual dearbox , you know if can i do something like this ?

[@sssnake2332]

I'm curious why so many people do this mod when simply putting the trans in 1 or 2 achieves the same thing. Is it so you can have 50/50 split in 3rd and 4th gear, and if so, when is that useful and does it hurt your MPG?

[@jasperamerican6642]

are you sure that works i have seen videos of foresters that would prove otherwise

[@philiph9578]

My 03 impreza outback sport will lose lock at higher rpm, in first or second. Makes passing people or drifting difficult. Same thing with my 01 forester.

[@MihkelOviir]

Wrong. It is needed for example slow offroading (what offroading generally are). 1 and 2 gears will be 50/50 only on full throttle.

[@joerodriguez3002]

What about In a manual trans. What do you do

[@sssnake2332]

@@joerodriguez3002 Manual trans you burn the clutch or just send it at 20mph.

[@aaron31659]

Does this work in the manual transmission?

[@SchutzStaffel1989]

Can this modification be made to a 2008 outback 2.5xt?

[@EDDIEGARAGE]

A great tutorial is this would be the same as turning off the Vehicle Dynamic Contol? thanks

[@robertzumwalt1098]

What about a 03 forester with a 5speed

[@walkerfamilyvending6989]

Question I noticed in my 05 foz XS auto that there’s a wire taped to the wire for my cruise/defogger buttons, is that a pre wire for something? Like if I put another button there?

[@kostasKazama]

Its still an all time 4wd but with locked dif like tractors have. The whole point of having a subaru is to make the dif act like a tractor or like a Suzuki Jimny where you can have RWD or 4WD with a push of a button. Informative video though, well done

[@brananandreu4086]

would this work on a 2015 subaru outback? and other than cost why do this as opposed to a actual rear diff locker?

[@saxtonmickhi3742]

Great video imma do this on my 06 Outback tommrow does anybody know if it will go smoothly with my model

[@pholland6643]

Does this work with other AWD systems like Hyundai?

[@JohnKihl]

I have a 2012 subaru forester with a TCM, which says DT on it, which 2 wires are you cut into? Please see picture

[@spl9971]

Hi, I have an xv 2019, the 4×4, the computer gives it power to whichever wheel it wants, and I had several situations where the computer decided not to let it give power to the rear wheels, and it only worked forward, and the car would sink in the sand in front, and the rear wheels did not work.I saw that a button can be made Give a physical command to the computer or to the chalk to let the mocks back work, have you done something like this, can it help me

[@pellcio]

Is this mod useful on MT cars? Shopping for an SG right now for off road driving. I'm on the fence as to which transmission to go for. Thanks.

[@michaelyarber6821]

On a non turbo 02 Impreza why would I install a 100 ohm resistor? Seems to me like I would just leave it open.

[@ag6907]

I have a standard 6 speed though.

[@jimebe602]

Does the diff lock work in while in Reverse gear? Or is that not advised??

[@fredastaire6156]

I wonder if this will work on a 2012 forester?

[@leroyaeschbacher2372]

Okay so I've watched your video 12 times and I've been all over the Internet pulling my hair out I have a 2005 Subaru outback non-turbo and I can't find the wire to cut to install this switch on my TCM. Nothing on the Internet or any diagrams or pinouts gives me any specific color of wire

[@dadbodgodbod]

Will this work 9n the outback 2008 2005 with the 3.0 engine and at gearbox?

[@Panmei943]

Hello. i followed your instructions and i have this mod for a year now and it works flawlessly. The only thing that i wish is to be able to install a ligth on my dash when i have the switch to ON. I wonder if there is any way to do this on the existing setup

[@douglasfrompa593]

How anout a lit switch? Or a lead from the load side of the engaged pole of the switch to a led bulb in the dash. Might should work?

[@DavidNieuwenhoven]

Has anyone done this on a SGXT as I want to do it but cannot find that resistor in Australia only the USA. How important would it be to get the correct one? Any auto electricians here?

[@AngelPerez-nl5or]

works on 2006 Subaru Outback non turbo automatic transmission

[@hermannjosesylvarnes3094]

Donor Work on your Subaru outback 2006 2,5 i automaticik

[@MonkellD]

Will you please help us see if this will work for other cars, 2015 impreza here!

[@jerominefelixcantoneros393]

Can this mod be doable to the 2022 or 2023 Ascent? Thanks

[@foresterboy2011]

Hello fella, I'm a UK 🇬🇧 guy and we get the 6 speed manual diesel. Is this only for automatic transmission models. Please advise???

[@AWDfreak]

The manual has a viscous coupler, which purely mechanically distributes power between the front and rear mechanically. This cannot be done on a manual transaxle non-DCCD Subaru AWD. You will need to get a stronger-lockup viscous coupler from STI or AllDriveSubaroo in Australia for better off-road performance.

[@PanicSkateboards]

En estandar se puede hacer ???

[@dysonspreybar4903]

can this cause any undue strain on other components?

[@AllanLove-in7zr]

Can you do this with a manual transmission?

[@michaelkukkola1900]

This sounds great, can i do this on my -08 na outback with manual gearbox..?

[@michaelkukkola1900]

???

[@vijayanchomatil8413]

So let me get this straight. It only works when the throttle isn't used?

[@matteoperron5436]

no, you just dont want to do sharp turns with it on while driving on pavement, because it is rough on the diff and tires. similar to a locking diff on pavement. when you are on loose stuff you can turn more freely cause the wheels will just slip.

[@christopherlong5928]

I just found your video!! So awesome!! Do you happen to know if I can do this to my 97 with a 4EAT?

[@thespiritofthenight8196]

I cant get it to work on my 2000 subaru outback. I wired it up just like in your video but it still doesnt work. could you help me?

[@lukeshifflette1904]

Has anyone tried this on a gen 4 ra WRX with the FA20? The thing I like least about this car is that unless you have snow tires it is garbage in any kind of snow. I want to be able to lock the diffs when stuck and raise the suspension a few inches, then it will actually be a good mountain car

[@tokyotopp]

Can’t you just put it in 1?

[@rexxbare9255]

Depends on year, but he’s talking about a 4 speed auto specifically. My manual does what his switch says it does from factory

[@tokyotopp]

@@rexxbare9255 I have a 98 Subaru Impreza outback sport. P R N D 3 2 1 4eat From what I understand putting it in 1 is 50/50 2 is 60/40 something like that??????

[@mattmaleyd.c.4047]

I have a 2016 base Subaru forester standard. Would this work in this model? I know you talked about the 4 speed auto, but I'm still good old clutch and shift.

[@adibhachem5773]

Hi...it s the same for outback 2010 ?please can u help

[@kimlundy7575]

can this be done in a 2021 outback CVT

[@bumndrass]

Dammit I'm wanting to do it on my manual SH turbo diesel.

[@pajehh]

Is it possible on the sh?

[@bumndrass]

It is after trying and setting it up. I'm about to put a video up in the next few weeks.

[@TheScares80]

@@bumndrass did you end up posting a vid? I’ve got an SJ turbo diesel manual… and I’m very interested:)

[@simr2105]

It will not work on a manual Forester as they use a mechanical viscous centre lsd .

[@blindstudios1082]

Can I do this to my 2017 crosstrek? Or do I have to buy lockers?

[@COWGIRLMOTORSPORTS]

Will this work on a 1999 Subaru Legacy L 30th Anniversary Edition Auto??

[@MrDvirpariente]

Hi do you know if it can be done on a 4 gen? the one after the one you use.

[@kuzya19989]

Is this wire going to the Transfer Duty solenoid? I was looking for the Electrical Specification for TCM of my 2001 Subaru Outback H6 3.0 L.L.Bean, it has 4eat but doesn't have VDC. Is it still possible to do the same with it?

[@sourgrapezproduktionz7028]

will this work with any subaru

[@motoflyte]

You didn't take it off road and shoot a video.... I'm kinda bummed dude.

[@ratikobakhidze1294]

Hello, Could you tell me I own Subaru Baja 2003 Turbo AT with Sport Shift, it is kicking when shifting from 2nd to 3rd gear, master told me to replace Transmission Computer which I can't find, mine is 31711-AJ000 , Could you give me any advice which replacement TCU might work with my Baja, transmission code is : tv1b4mhfaa , and rear diff is 4.444 VISCOUS LSD. Thank you in advance

[@Loewenherz6183]

Will it also work on the manual transmission???

[@OnyxGrizzly]

Manuals are 50/50