Changing Subaru Rear Differential Fluid | 2015 Subaru Forester | Drain & Replacement of Gear Lube

[@bygonebob]

Please don't skip ads watching all MT's maintenance instructional videos, fellas. It's the only way we can repay him. God bless, you all. ❤

[@nastysoda9212]

thanks again! quick story, I was going to let the dealer do my diff oil change, front and rear. Cancelled last minute because I know I can't trust mechanics anymore. So went to the dealer to buy the fluid and gaskets. The parts guy said "you don't need those crushw asher, we jsut pop the old ones back in. They also don't use subaru's gear oil, they use some generic junk from a barrell. We really have to do all maintenance ourselves now. Dealer or mom and pop, they all seem to be trash now a days.

[@thegarman]

Excellent and most helpful. You covered ALL the bases and the Front Differential video was equally excellent. I'm very handy and good with cars, but it's so nice to be able to see the entire job before tackling it. It's also helpful to gather up everything you need (gaskets, torx socket, etc.) beforehand! THANK YOU!

[@MTsubfly]

Thank you sir for the feedback!

[@cztech2631]

This video helped a lot. Those plugs were so stuck in there. I think the Forester never had the rear differential serviced in 150k miles, so I decided to do it myself. Some of the hardest plugs I’ve had to break loose. Breaker bar really had to get wailed on hard to break them loose.

[@Doc1855]

On all our vehicles I change the oil every 4K miles with Mobile 1 full synthetic. Every 30K miles I change the front and rear differential, transfer case, and transmission flush. Our 11 Ford Ranger was very noticeable during up shifts with the 5spd auto transmission. At 30K miles I had everything done as normal and now the transmission shifts as smooth as silk. Currently our Ranger only has 35K original miles and it’s almost 12 years old

[@rhiiine]

Just knocked this out at 80,000 miles. Thanks! Coffee coming your way. Now on to the front diff.

[@RYoyo-do2on]

The rear differential gear lube change was spot on, thanks! More trouble with the front differential.

[@disenchanter]

Damn, i feel pumped to do this myself after watching your tutorial. Thank you, Holmes!

[@stacimcclendon3907]

Great job laying it out- tools, fluid, describing what you’re doing and how to do it!

[@spelunkerd]

Every time I do something on the car, I think about doing a video to raise the bar as far as what's out there on KZbin. No point, I couldn't do better than this one, ha ha.

[@MTsubfly]

Thank you!

[@gvjester]

Beautiful video, covered all the important parts and didn't introduce your dog, which I'm sure is sweet but doesn't figure into the video. Thank you very much!!

[@Keanu1209]

love your videos, looking forward to see if you have one about changing the spark plugs on the Subaru.

[@annabrannlund8887]

Very good video and explaining, thank from a Swedish girl👏👏

[@theresahoffman8408]

Approx how much fluid? Will 1 quart be enough? Always make sure you loosen the fill BEFORE draining. You wanna make sure you can refill.

[@KarlitosJimenez]

muchas gracias por tu video.... te has ganado un suscriptor

[@snowobarder27]

Man I love your videos they are super helpful

[@Gopal_1111-o2s]

Awesome video dude..👍👍 now i can change my Subaru XV differential oil my own

[@ledzeppelin1212]

Very helpful video. Thank you!

[@Honestandtruth007]

WOW...... I never knew that.... My Forester 2014 at 63,000 Miles.... not yet change differential fluid on the front or the Rear....😔

[@Javii96]

crush washers in video: x2 - 803918060 If you're doing the front dif also, you'll want two additional, plus a larger one with part number 803926090

[@DIYBIGMAN]

Great video it was helpful!

[@jgzero18]

Looks super easy, thank you

[@Grad3r]

You can replace fill plug for magnetic one as well

[@kostadinustavalkov1902]

Thanks bud very helpful! Just changed both mine on 30k and rear looked dirtier than the front. Sent a sample in so we'll see how it comes back . By the tube looks like you using blackstone lab too if I'm not mistaken ☺

[@MTsubfly]

Thanks! Good to hear! Yea I use Blackstone sometimes. I didn't end up sending in the samples and they have been sitting. Pretty crazy to see the stuff that settles out of the fluid when it sits for a long time. (This is another reason why we change fluids) 😆

[@kostadinustavalkov1902]

@@MTsubfly good deal 😊 ,yes absolutely fresh fluids make a big difference. How you doing on your cvt fluid? I took a sample from mine and sent it to Blackstone...guess what...results came back bad and had to change it at 30k 🙄

[@MTsubfly]

@@kostadinustavalkov1902 mines doing great 107k miles now. That sucks! What did they say was wrong with it?

[@kostadinustavalkov1902]

@@MTsubfly dang I guess I got lucky about that lol . In the analysis everything was fine just insolubles were .2 while the limit is .1. I call them and they said basically that'll make the fluid abrasive coz those mean oxidation.

[@MTsubfly]

@@kostadinustavalkov1902 yikes! Wow! So this could be a good example of why changing fluid is important. Filters only filter so much. Changing fluids removes a lot of insolubles that build up. Still I imagine something was causing excess wear. Replaced under warranty?

[@glock-hm3ro]

Great video seriously! I have a 2021 Forester I bought new in 2020 with only 22k on it now so I’m planning to to the diffs myself then have the trans etc done by dealer. I’ve had several Subarus since 1998 and usually did all the diff. Maintenance myself due to it being reasonably easy. One question: did you lift and level the entire car for this??? Thanks again I’ll watch the front diff video next.

[@mangogrower5426]

Thank you 😊

[@62Cristoforo]

Wondering if those new O-rings would ‘double over’ with 40 ft/lbs on them? Maybe opt instead for flat fibre washers?

[@cdidanhal3322]

Oh man you are saving me from paying $1200 to a dealer to rotate and change differential oil. Thanks again easy stuff to do on my own. thumps up

[@glenthecarguy]

1200?

[@cdidanhal3322]

@@glenthecarguy Yeah they charge a lot, i should post a print paper they give me with prices, brake light bulb $120, Windshield replacement i have crack for $850. once they want to charge me for brake pad rotor for 4 wheels $1400.

[@Dan007UT]

@@cdidanhal3322 in what country!?

[@cdidanhal3322]

@@Dan007UT USA

[@Dan007UT]

@@cdidanhal3322 I just ask because that's a crazy amount!

[@auto247garage7]

Good jod. I from Việt Nam. Thank you.

[@auto247garage7]

I love Subaru kzbin.info/www/bejne/f4O5Xn1nms1opcU

[@mdhoore]

Well done.

[@billzziv6859]

I let the dealer do mine today at 40,000 miles. I would seriously think about doing it my self next time however. Where is your video for the front differential?

[@MTsubfly]

It's pretty easy you got this kzbin.info/www/bejne/Zl6QlKd_dparlZo

[@mynameiskenny01]

1. How crucial is it to use OEM differential fluid and crush gaskets? Is it possible to purchase from sources outside of the dealership? 2. Would using brake cleaner to clean the differential be okay? 3. Would just rubbing alcohol be sufficient to clean the drain plugs?

[@MTsubfly]

1. Using OEM oil not crucial, but Subaru oil is "designed" for the metals/wear in the diff. The oil you use must meet what is called out in the manual for viscosity (75w-90?) and specification (GL-5?). It will say on the bottle what spec it meets. You could reuse the gaskets, just clean them but you risk leaking, or a blown out gasket, or not proper toque up. With gaskets being cheap, its always best to just replace them. In aviation, every gasket gets replaced after it's used once...as an example. You can purchase outside the dealer, but you need to know the gasket sizes to find a suitable replacement. Ordering a subaru gasket is easy and correct. 2. Do not spray any cleaner into the differential. Only clean the exterior before removing the plugs to keep dirt out. Brake cleaner should work well, its strong stuff, use caution. 3. Rubbing alcohol can work well. Its gently cuts grease and oils off of surfaces. Brake cleaner, or carb cleaner if a very volatile aggressive cleaner, which can come in handy if used correctly. Compressed air also comes in handy for cleaning.

[@mynameiskenny01]

@@MTsubfly thanks for the quick response! On a different note, what size Torx bit did you use to remove the plugs? I'm guessing these are the same for the front diff, correct (haven't watched it yet)?

[@MTsubfly]

@@mynameiskenny01 you should watch it! Depending on model and year of your car. My rear diff was 10 mm hex. Front uses Torx. Check out my front diff video.

[@dvnjhnsn2000]

Thanks a mil it really help however is there a front diff?

[@MTsubfly]

Right here! kzbin.info/www/bejne/Zl6QlKd_dparlZo

[@mistone9784]

I think I need to change mine 97 outback Impreza notice when I back up and turn it makes a knock looked at the gearbox and looks like it's been leaking out

[@fortisfabrications4558]

Only critique is the extension on torque wrench. Not an accurate torque. But It will be fine. You can compensate next time for the extra inches.

[@MTsubfly]

Actually the torque is accurate. I'm very familiar with torque wrench use as an aviation mechanic. Extensions won't change torsion applies unless you use a crows foot, dog bone, or change the distance from the center of applied torque. This is fake news, sorry.

[@hcyybyq]

hi there, thank you for the detailed video. i'm looking to get front and rear diff fluid changed as well on my 2017 Outback, when i'm shopping for the fluid, should i go with limited slip or non-limited lip? the owner manual only shows GL-5 75W-90. Thank you advance.

[@JohnBoyJoy]

Great video. 👍

[@greganson3627]

With that extension and swivel, you might want to recheck your torque without them...you're probably quite a bit lower than you thought.

[@MTsubfly]

Extensions and the wobble won't change torsion applied unless you are off center. If you are off center off the torque wrenches drive you can apply mathematical skills to adjust. The most common example is using a "dog bone" torque adapter and depends on how close or far away from the torque wrenches center drive you are. I was slightly off center but not much. The purpose of torquing for me is too not be excessively low, or so high it strips out, in other situations you need an appropriate clamping pressure.

[@sandyshoremann7524]

It' s diff plug. Not a CYL head bolt or WP bolt. I wouldn't have a torque wrench anywhere near that job.

[@dayledonne8272]

Does your Fozzy not have a rear diff temp sensor?

[@mcase003]

Dealer did a diff fluid change with 60 service. Took me a week but noticed fluids all over driveway. The dealer admitted wrong doing saying plug wasn't quite sealed back in. Any serious damage done here with the diff fluid leak?

[@artfisher1235]

Excellent thanks

[@jtwu8931]

I did it myself and it saves me $150 what AD charges. Thanks

[@michellek.5775]

Nice Job !!

[@VE8HL]

2 questions: Is the differentials the same for an automatic transmission vs a manual gearbox? Also how much gear oil is required for each front and back?

[@MTsubfly]

More or less it will be similar between manual/automatic. You will use about 3 quarts. Get your VIN # and call a dealers parts counter and they can tell you 100% for sure. Goodluck!

[@jkxss]

You need a 13 mm socket. www.amazon.com/gp/product/B07QJ6V3GV

[@SatnamSingh-pn7ob]

Nice

[@JohnResciniti]

36.9 ft/lbs Boy, I guess subaru has some pretty specific wrenches. That said, I don't think torque wrenches are accurate once a wobble and extension are used. I'm sure you did that for the purpose of showing us with the video. Just reinforcing that ridiculously specific torque spec. I'm sure 37 would be fine. I'm sure 35 would be as well.

[@Nachiebree]

It's a Japanese car- 36.9 ft-lb is 50Nm which is a much more reasonable sounding spec. 51.6ft-lb is 70Nm

[@EAADetailing]

Im assuming yes, but is this the same as the '16 forester XT?

[@MTsubfly]

Should be 95% identical. Gasket #s, oil volume and grade might be slightly different. Process is similar. Consult your owners manual for exact grade.

[@schumacher47]

Where did you get that plastic pump with clear tubing? How much?

[@MTsubfly]

Walmart $6

[@garym.walters4585]

👍Excellent

[@chillrasta12]

Was just wondering, have you had any problems with oil burning on this Forester? I was looking at picking one up and heard this was a common complaint. How many miles do you have on it now?

[@MTsubfly]

We have 107k miles. We typically use 1 quart in 5k miles. I change the oil every 5k. Its stayed about the same since new. In my opinion this is normal for this engine. I wish it was better, but being horizontally opposed it naturally burns oil. No oil leaks anywhere. No signs of head gasket problems either...knock on wood....

[@kostadinustavalkov1902]

Mark i have same year but non turbo ,32K rn and haven't seen any oil consumption yet ,using Mobil 1 extended and change it 4 to 5 K

[@user-dz6zd2sk5c]

Where do you order your replacement gaskets from? Have it trouble finding a non sketchy/ridiculous priced source. Thanks

[@MTsubfly]

Through the service center at a dealer, gaskets were cheap, like a dollar or two.

[@user-dz6zd2sk5c]

Thank you!

[@brianentz2785]

how many quarts will i need to replace the front and rear differentials? About.

[@MTsubfly]

3 i believe, but check your manual on viscosity and quantity and you will be sure!

[@josephsessaph.d.3575]

Be careful when you torque. Using an extention will change the value and the torque and it will be different from what you set the tool at.

[@ericr2zz]

As long as the extension is rigid and not an an angle to the plug, there will be no change in the torque value.

[@4turtlezhu839]

I had the same car bro! Can you list all the tool a link to buy? Thanks

[@MTsubfly]

Thanks. I used a lot of general tools, like pliers, screwdrivers, picks/all, etc. The only specific tool would be a socket for the nuts (8 or 10mm) and a torque wrench which is not mandatory. This is a job that requires some mechanical aptitude more than a toolbox of tools. Thanks, let me know questions.

[@4turtlezhu839]

Okay thank you

[@4turtlezhu839]

Sorry ! I can’t find them! I’m new ! Can you list a link I can buy those tool on your video shows 4 tools on the table ? Thanks a lot

[@Pizdzirynka1]

Serious?

[@l...]

Is it ok 75W140

[@jeffstowe2113]

Do you need to add Limited Slip additive for the Subaru differentials?

[@sandyshoremann7524]

They are not LSD. Subaru and most car based CUV are two wheel drive - one front and one rear - the ones with the LEAST traction. Ill let someone else explain ASR and traction control.

[@chuckknox7400]

Capacity of oil would help

[@usmc4301]

1.5 quarts for rear and 1.5 quarts for the front

[@Condor1970]

What about the front differential?

[@MTsubfly]

It's an another of my videos, just click on the channel and go to videos! Cheers!

[@Condor1970]

@@MTsubfly Thanks.

[@davidaud4652]

what do you need the sample for?

[@MTsubfly]

Some folks send it out to be tested, to tack and trend wear metals. I'm not doing that, I just wanted to show it, and have a sample for filming.

[@Pizdzirynka1]

Your old oil doesn’t look that bad

[@MTsubfly]

I didn't think so either, and that's about 70-80k miles. The Forward Differential was a lot darker than my rear.

[@kostadinustavalkov1902]

@@MTsubfly that's strange ,when I changed mine the rear was darker and lab results showed rear one was in worse shape than front

[@jimwillingham8052]

70k miles is far too long to allow diff fluid to be in the differential without a change.

[@tylerramos7633]

How much gear oil did it take to fill?