Why your Off-road Subaru needs a locking center differential and how to install one for free 

BIG NEWS - Torq-Masters is coming out with the first affordable SUBARU R160 LOCKER ever (thats the rear diff, not the center). These bad boys are scheduled to hit the market this summer for just $400, but we'll be getting some prototypes in soon to test and review! We're looking forward to seeing how they perform both on-road and off-road. Check out our social medias for more info, and subscribe/follow for install and testing updates as stuff happens.

Cool channel! Good info, good presentation! Thanks for sharing

very good explained, BUT this is basically no diff. its a clutch... a center diff is just the same like diff in an axle, but i'm sure you know that anyway. :)

I had thought the center diff would automatically split torque 50/50 if you lock the auto trans into 1st or 2nd gear. Is that not true? I have a 2009 Forester.

NEVER do this to your daily driver, leave it factory. This mod is ONLY for beat up off road vehicles you don't really care about.

This is such an awesome video. Super helpful and excellent explanation. Pitty I never heard of this before I sold my Outback!

Hello , can that mod be installed into a Forester SH 2.0 5MT Transmission Type : TY758XTZAA

Curious how this works with the CVTs

Can i do this to rx300 awd 1999

Seriously though this was a Regular Cars video at times.

Swapping in the vtd center dif with a static front/rear distribution ratio of 45/55 and extension case in place of the pro-dominantly front wheel drive mpt center dif is a great “upgrade”. The vtd dif can be sourced from a number of 4eat’s with Vdc/vtd. You do have to install the “awd diagnostic fuse” in fuse box under hood due to difference between the two difs. The fuse simply disables front wheel speed sensor. The vtd center dif is an open dif but still has a transfer clutch to “50/50” lock the awd, So adding the dif lock with the vtd works great for me.

Please any information further on this would be greatly appreciated I've watched your video over and over again and I also like And subscribe to your Channel thank you for turning these old Subarus into something absolutely amazing dude

Such a good video! I thought this would be much more complicated and im amazed at the difference it made. Great explanation

I did this on my old 01 Forester years ago. Works like magic just DON'T drive it on the road with it on. Bad stuff can happen...lol

Okay so I have been digging absolutely everywhere trying to figure out if this modification is only done in a 4EAT with the MPT or if it can be done on both MOT/VTD and I have been trying to figure out whether my 98 legacy outback limited 30th anniversary edition car has the damn MPT or the VTD and I still can’t find that info... I think after searching everywhere and reading a billion threads and brainstorming how in the hell this all works etc etc I need an answer to this and I hope I can get a reply. This switch mod to control the solenoid is ONLY done on a 4EAT with MPT “center diff” and NOT on the 4EAT with a VTD “center diff” am I right or am I wrong? Can it be done to both or should it only be done to one or the other?!?! Gaaahhhh my brain is on fire 🔥

Open up the cover get your old stick welder out buzz box. Hell get some jb weld and coat them spider gears with the biggest fattest booger of a weld or glob of jb welder

Bro how can I get a schematic of the relay hook up a few weeks ago I blew up my center diff due to tire spin. This videos was absolutely just what I needed you guys rock!

Thank you!!! You delivered

Heu guys just wondering if this sort of thing can be done on a manual gearbox in the subaru? Im new to all this ive just lifted my impreza but pretty keen on 50/50 4wd so its good to go. Also if there is a manual tranz what code is it and what are they found in that i can hook up a switch on? Thank you

will this work on a 1999 Subaru Legacy L AWD??

Hi there. Thanks for posting this! You’ve got my gears turning for my next mod 😜 I drive a lifted 07 Impreza w/ auto tranny. I’ve heard that in 1st and 2nd gear it does lock. It may shift to third if it senses high rpms though I’ve heard too... I’d like to do this eventually but if I can get away with a locked diff in 1st or 2nd then I might work on other things before I get to this. Have you heard of what I’m talking about? Can’t seem to find it anywhere. Thanks again for posting this tho, f*ing great 👍

Ok is this the same as the FWD fuse in the 2003 OB H6? If so I believe you are saying that you're now driving in FWD mode until you hit the switch? My transfer clutch has shat the bed and I'm running with the AWD fuse in place. Can I do this indefinitely?

Hi, I have a Subaru Forester 2009 and would love you lock up the centre differential please could you help me. Regards Dale

I figured out a more simple dummy load. Still testing but I can email anyone the schematic if interested.

I found this old thread on RS25 if anyone is interested. www.rs25.com/forums/f8/t99075-4eat-diff-lock-switch-handbrake-mod-torquemada-lite.html

My mum managed to drive my pathfinder about 20kms on tarmac in 4wd hi...ie with the centre diff locked...range me freaking out coz it didnt want to turn in the parking lot...asked where the drive selector knob is set? Ahhhhahhhh...

Will this work on a 2014 Subaru Forester 2.5 i cvt

I have a 2008 outback with 4EAT and checking my wiring harness i do not see a white and green wire. Do you know where to get the wiring diagram for my car.

How do i know if I can do it to my car? A 2017 6speed manual subaru xv

Wonderful video 👍 I learned a lot from this video. One question though. Will this work in a 1993 Subaru Impreza L sedan 1.8 auto AWD? Completely stock.

lol when i get my subi can i come down and build subis stuff with you guys?? lol ehhyy im a machinist.. and Canadian.. lmao

Hi thanks for the video, it looks great. do you know if it can be done on a 4 gen? the one after the one you use

Where is the complete wiring diagram so i can follow it!

ABSOLUTELY AWESOME! do you have a shop where you can do mine? 08 Tribeca. I like subarus but im not at all mechanically inclined. Please be in CA....please please please.

you guys are brains.... this is cool, but its a little too hardcore for me. i do appreciate the post however

Super knowledgeable and entertaining video, Subscribed!

hi my friend ,can do it with subaru tribeca b9?

respect

can you do this with a manual transmission?

YOU LOST ME AT RELAY... I was looking for a video on MANUAL LOCKER. Not sure what this does here...

this mod really reminds me of the OEM Subaru Forester 110V Power Outlet Kit. you buy a little box but really what you pay for is the diagrams that a show install and instill confidence that its not going to brake a critical part. (you could sell a pdf instructions) But this is one of the cooler mods that im going to have to now look in to So, thank you and Great work! (Because this message is prerecorded, any observations related to your performance are speculation on our part. )

I was wondering if you might be able to draw me up a diagram to show me how you wire the TCU into the Dual switch relay and what size specifically Ohm resistor you used to trick the TCU to think that it's the solenoid I think I understand what you did but I'd like to have a more firm understanding I would really like to do this modification on my 02 Outback

shit, what a brain, man good job

what about that 1st gear on 4eat ? i heard on those gearboxes 1st gear locks center as well. or its not ? and some people making that button like in 3 configs even. not just on or off. like if you give there other voltage then 12v you get slightly diff results. interesting info there, so you have VTD there ? so its like those VDC outback models ?

How much does this mod help with diagonal wheel spin? That's the only issue I have with my 08 Foz... and I feel like only a rear locker would help..

I need this on my legacy

Cool video, I was hoping someone could answer a question. I have a 2011 forester with a 4EAT and I've been reading online that the power distribution splits to 50/50 no matter what when in manual mode. Is that similar to this mod or is there a difference?

I believe VTD is system applicable to auto gearboxes with center diff, (TVxxx). You can lock them as well (as you did), but solenoid control has kind of opposite logic - it needs no signal to unlock and signal to lock. I swapped my TZxxx gearbox for TVxxx on SG5 and couldn't find proper TCU. My old one works fine for everything except center diff control, I had to cut this wire for now until I find proper solution.. Not a fan of resistor trick because it'll probably become quite hot. Manual gearboxes (at least in Imprezas) all have center differential (your old auto TZ* gearbox doesn't), and manual would either have viscous diff or DCCD (STi only). You can lock DCCD, but I can't see how you can do anything to lock viscous center diff without changing it completely.

Can somebode confirme that in Forester SG when you block on 1st od 2nd gear and set up button on HOLD than you have the same result 50/50?

Can a diff lock switch be installed on a 2016 Outback?

Nothing was straight forward about how you did but the process seams simple. You should make a how to video and actually show how you did it.

That's awesome, I wonder if you could use that gadget to remove your front shafts on an auto and have full time RWD, I heard the auto-majics just transfer all the torque to the front if you remove them.

It `s genius. It is a pity that I have manual gearboxes because a very useful thing. Greetings and I wish you further successes.

Can you do this mod and install a rear diff Torq locker?

Game changer

Hello, great video! I have a question about the solenoid/valve - it is normally open (no power = clutch is locked) - I remember that there was a change into normally closed (no power = clutch is open). Do you remember when was the change (2005?) and was it to all models are some specific ones?

Is this mod doable on a 2007 Outback 2.5 non-turbo (basic) 4EAT?

I am considering a 2005 3.6 outback with the 5EAT. Can I do this mode on that car? If I can't I am not buying it!

Which sundial tool is used for installing a locker in a 2016 CVT Crosstrek?

I like those practical based videos! I'm considering to get a rear torq locker for my SH 6speed diesel but i'm not sure if the center lock hack works for mtm aswell and if not make it any sense to get a rear locker without permanent "locked" drive to the rear. Maybe you can help me out

Is it possible to do a similar thing to a 2014 subaru outback with CVT?

Now you just need a rear locker and your good to go.

Can you guys tell me if there is any difference (beside the center diff) between the 4eat of natural aspired subarus and turbos? I'm running a WRX ej205 engine in my 1970 VW bay bus and want to install a subaru 4eat transmission (tz1a4), which came out an natural aspired car. I'll be converting it to 2WD, so the center diff won't be used any more.

Wow! Awesome modification! Would this mod work on a 2015 Forester CVT with MPT (no X mode) ?

Could this work on my 2002 Subaru Lancaster H6 ... trying to lock my center and get my rear diff with auto locker system.. please help the subi gang lol

Nice video, very helpful to know. Does anyone know if you can do it on a Subaru forester sf from 1997 ?

More parts needed for the Nerdwagen build

Great video. I was just wondering where you got your dpdt relay from because I can't find any

Hola como esta? Podrías ayudarme? Mi diferencial central está bloqueado permanentemente y está haciendo daño! Que puedo hacer?

Not sure what you mean by this "unless you wire it be able to keep the variable power transfer it has from the factory." Can you do this mod to a 5EAT VTD (outback 3.6) such that it changes nothing from stock programming except when you engage the switch and lock up the center diff? I was also reading on a forum that locking center diff on VTD is not recommended except for short periods of time as, unlike MPT systems, it's solenoid is not designed to remain engaged for long periods of time, since it naturally has a mechanical near 50/50 bias, it only engages for seconds at a time to pulse brakes when wheels slip. Also, thought the 5EAT lock-up was hydraulically driven, not electric - does solenoid actuate hydraulic pump? (www.subaruoutback.org/threads/center-diff-lock-mod.504289/). Dude in forum was also talking some WAY more in-depth stuff that I didn't try to fully understand yet: "Steps to achieve this: 1. Review the 5EAT wiring schematic to determine how they have wired the transfer solenoid. (If the TCU controls on the high side + or low side - of the solenoid) Determine where you can tap into the wire @ the TCU controlling the transfer solenoid. 2. Use a DVOM / Oscilliscope and take logs of the control behavior of that specific solenoid under operation by backprobing that specific pin on the connector of the TCU. (search backprobing if you are not familiar) This will tell you how the TCU controls the solenoid, using this data you can create a microcontroller based setup (like I did) to drive the solenoid exactly how the factory had originally designed. Key items that will need to be logged / recorded: Duty Cycle, Hz, Voltage, Amperage, Averages, Max / Mins, Wattage, Measure the resistance of the entire circuit and solenoid. You will need to take detailed logs under multiple driving scenarios to determine how the TCU control behavior is activating / not activating. I recommend utilizing RomRaider at the same time to log multiple PID's on the ECU and TCU, this will allow you to view rear wheel / front wheel speed differences / solenoid % activation / line pressure / RPM / Torque Converter RPM ect..... You are going to want to have this information. 3. Bench test and make a microcontroller / MOSFET based circuit to control a load in the same manner as measured in step 2. (I used a potentiometer to send a 0-100% command to a microcontroller which in turn output a control pin to my custom MOSFET circuit to vary the duty cycle output of the system. While at the same time matching the same Hz as the stock system used.) 4. Re-wire the OEM system to switchover the TCU load from controlling the solenoid to controlling a dummy "load" that has the same or very close ohmic drop / amperage as measured in step 2. This will allow you to control the transfer solenoid with your microcontroller / MOSFET based custom circuit AND trick the TCU into thinking it is still controlling the transfer solendoid. While also not overloading or damaging the control circuit in the TCU with the dummy load. You don't want a fried TCU! If done correctly this will trigger ZERO engine or TCU codes and have ZERO effect on vehicle drivability. I used a DPDT switch to move the load between the solenoid and dummy load, which also had a built in potentiometer and simultaneously booted the microcontroller while activated. (This switch is my Avatar below my name) When the switch was off the vehicle was essentially stock, nothing was different. And that's all there is to it! You can figure out the rest :D Also to add onto RoughDiamond's note on NOT driving the solenoid @ 100% for long periods of time. This is absolutely correct, you are not going to want to over heat and fry this solenoid, its not designed to run @ 100% duty cycle. When I still had my Outback and used this setup I would drive it to 100% for very short periods < 1-2 minutes. With the different driving scenarios / in conjunction with RomRaider logging and the custom controller you can determine what threshold of minimum duty cycle is needed to eliminate F/R wheel speed differences. Logging F/R wheel speed differences (on loose terrain) and find what minimum line pressure (duty cycle) on the clutch pack is needed to provide sufficient lockup. In layman's terms: You can dial in the absolute minimum amount of pressure on the clutch pack needed to lock F/R together. This limit is of course going to vary depending on terrain and amount of Torque or load you are demanding from the engine. By keeping this to a minimum you will limit the risk of overheating and damaging the solenoid." Easy, right!?

Thats pretty neat. will it work with the 5 speed auto the 2007 outback has?

So I've got an 03 Baja non turbo I'm wanting to do this to. Is the 03 4eat normally with or without power? And is there a video going a little more in depth on how the DPDT switch is wired to reverse the logic so the light has power when the switch is doing its job. I'm a more visual learner sorry 😅

Which is "better" when locked, mpt or vtd? I understand that vtd is pretty much superior to mpt when unlocked and controlled by the tcu. But once locked, is one stronger than the other?

If the MPT center diff was replaced with a VTD center diff wouldn't you just need to put a 10 amp fuse in the FWD slot in the engine bay fuse box to "trick" the TCU from throwing a code, then all you would have to do is remove the bulb from the dash cluster 😎

If im not mistaken simply putting n/c relay in line w solenoid and adding switch would simplify setup and when not activated unit would remain controlled by tcu. No resistors needed, then it would maintain vtd

This was *awesome* Wish I could implement something similar on my 04 XT 5 speed manual for those messy twice a year situations I always seem to get myself into. Awesome video, cheers from Wisconsin! 👍👍 🙋‍♂️

Hey man can you guide me how to do this on my 2000 Subaru forester ?

With that veepak obd2 reader ive gotten tcu errors cus it jams up the com on the ecu

Is there a way to do this on a 5 speed manual non CVT?

If your Subaru needs a locking diff, you need a 4WD and not a Subaru.

Hi there awesome work btw I have a lot of questions but staying focused to this video this has nothing to do with the factory "on/off" tcs button right? And if not does it work for 08 manual transmission ? Last but not least 😅 how would it work with the tcs on or off? Feels like a newbie question but hope you can learn me 😌

Okay so I have a WRX that I recently put a STI trans in (has DCCD). I swapped because my old WRX trans was squeeling from the rear of it. I do a lot of offroading (cell site technician) and now I know why it failed. Thanks for the lesson!!! (Btw I ended up using a MAPDCCD.)

What models of subies does this mod work on

Can’t you just put it in 1 to 50/50???

Separate question: seems 5th gen outback brake traction control is much better than 4th gen outback. I am comparing 3.6 4th gen outback to any 5th gen outback. Not sure if difference is more a function of MPT vs VTD (i.e. CVT vs 5EAT) or 4th gen vs 5th gen, even comparing 4th gen 2.5CVT/MPT to 5th gen 2.5CVT/MPT. Also take x-mode out of equation, since 4th gen does not have. Thinking of buying 4th gen 5EAT b/c I like feel of VTD, but for off-roading it seems like a trade-off - more wheel slip and less aggressive/effective brake traction control, so probably puts more power down for snow drifting, mudding, and hill climb, where you want momentum and wheel spin, but can be more easily defeated by off-camber situation (or any situation that causes traction loss to at least one wheel on both axles), so worse for slow, controlled wheeling. Is this accurate? Anyone have lots of experience with both systems? I'm basing this on comparing lots of vids and limiting driving time I've had in both cars - haven't had a chance to test with rollers or do extensive off-road testing to be sure. With all the subaru nuts on the internet and suby meets that I'm sure go on, frankly I'm stunned no one has done roller tests with all gens/systems on outback and other models side by side to clearly show differences (would be really easy - just bring rollers, or some small ramps, and film it).

Also- do you have any clue if the TCU and VDC systems on the newer ones are integrated / linked? I'm worried if I swap out the rear bell housing of my tranny for a VTD one (with all planetaries n shit of course) it'll screw up my vdc. Also heard there's an issue with the front and rear output shaft tone rings being different- hence it will throw a tranny code. Some people solved by inserting front wheel drive fuse and using a switch to supply lock up voltage when needed. Can a custom tone ring be made? Im worried if I run my standard tcu with a switch mod controlling the VTD clutches that it'll throw a code- and whilst I might be able to get it cleared, it'll disable VDC completely (or even abs too- like when you pull the VDC fuze to completely disable it). Sorry for all the questions Thanks in advanced

Hi, I just watched you video, and i have a 2001 subaru outback with a 4eat in it and i was under the impression that if you shifted it down into one that it locks the center diff for a 50/50 split front/rear. Is this not true? I don't really see why you'd really need to have the center diff locked outside of first gear unless you where rallying on a smoother offroad surface, but for just trail riding if all i have to do is shift down to 1 to lock the center diff i think that's good enough for me personally. BUT if that's not the case id like the switch wired to where it works like normal with the switch of, and only when you turn it on does it override the TCU and drop the voltage to that solenoid. I don't think that's how you did it, but said it could be done that way. So yeah, that'd be nice to know if shifting down to 1 provides a 50/50 spilt.

I may be missing something, but I can't seem to find a clean way to wire this up for a car with VTD from the factory. I've got a '12 3.6R and am getting really interested in installing a controller for a sort of auto DCCD, and I have no idea where to find this info.

установи хвостовик от TV на TZ коробку, думаю тебе понравится.

Hi, can you do this mod to a manual Gearbox on a 2.0 SG?

Question if i have a ty754 or a subaru 5 speed then how do i do this? I think they dont see the 20lb sti is made anymore and i dont want dccd

What differential is on the current 2018-19 XV? Will this work on it? The Torq Master?

What are the options to improve off road capability of the dual-range manual transmission Imprezas?

Can diff lock switch be installed on a 2014 Subaru Outback, forester

I'm new to Subaru world, I bought mine in December 2019 I have a 1997 legacy with the 2.2 and an automatic. Do I have any options for a center differential selectable locker? Thanks

Is there a way to do this to some of the newer models? Wife has an 18 Outback, and I'm looking at a new Crosstrek. Mine will definitely get off roaded.

hello, so theortically, if i do this mod and remove the front axels, i can have rwd in my subaru?

Just watched this, very interesting and innovative! Can this be done to a 2018 Crosstrek?

Nice! Thanks a ton for all the info & great explanation of it! Always thought there was a diff more like an Audi or my Land Rover's transfer case, not that it's a negative, just more simple than I expected! I'm going to have to get after this mod quick-like.

Te felicito, es impresionante lo que lograste, yo tengo una forester año 99 T/M, con palanca HI/LO, se podra hacer en mi forester ese invento?? gracias, saludos desde Chile...