Subaru Outback Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1 (Edited)
I just changed the rear pads on 2017 legacy sport with automatic rear braking and electric parking brake. Don't know which changes the rear brakes. but after watching several u-tubes on changing rear pads on earlier models I started with my 2017 legacy and came to the outback.org since i can't find one for legacy and was told most things on legacy and outback are the same. REmoved the wheel and tried to use screwdriver to move the calipers to push the round plunger ( cylinder) back into the calipers rather than buy a compression tool. per videos on earlier models. The caliper wouldn't move, was locked in place. then looking at the back side I saw an electric device which I assumed was the device that activates the parking brake and perhaps the auto reverse brake when someone comes cruising cross your rear when you are backing. Whatever the device is for. It locks the pads so it won't let you retract the caliper piston. I've had cars before that use disc brakes and mechanically use the dic brakes as parking brakes and and found them to have a plunger that rotates on some threaded mechanism so it continually tightens as the pads wear and it needs to be retracted in order to allow the cylinder( plunger) to be pushed back inside the caliper to allow new thicker pads to be installed.

You need different tools to change the pads than shown on the earlier model videos. If you have a 7mm metric hex wrench socket( male) for loosening the caliper, a 5mm metric hex wrench socket (male) , and a female 12mm star , or torx socket female ( craftsman E12), screwdriver, needle-nose pliars,you have pretty much everything to do the job.
Loosen tire lug nuts. jack up and remove tire, first thing you see appears to be two rubber tubes covering the back side of the caliper slide pins, do not try to use a pliars to remove, they protect the slide from dirt. but there is a plastic cap on the end that can be popped off using a standard screwdriver, apply to the very far end ( away from caliper body) and the ribbed plug will come off, do that on the top and bottom. You can break the caliper attaching/slide bolts loose with the 7mm hex wrench socket. it takes possibly about 20 ft pounds of torque. Then the key is to also remove the black plastic housing on rear side of the caliper assemble that electrically tightens the calipers, with 2 small metric screws with the 5 mm socket, Note how little force is required to remove the 2 bolts holding the electric assemble form the brakes. you should not need tools to remove the electric assembly, once it is loose. (or at least on my legacy it wasn't hard * 80,000 miles in 3 years, vehicle in climate where salt is rarely used) I twisted the assembly and it came off and had enough play in the wires to let it dangle down to the ground. Now you will see the Torx or star extended out from the caliper assembly with probably some grease on it. , I put the torx 12mm socket on it. and very carefully twisted it in what I had thought was the loosening direction only to have it turn less than 1/4 turn before it tightened. Try to also note how much you moved it. Now reverse the direction until if comes to a stop going the other way, couple of turns and i was able to turn it using the socket and my fingers, or extremely carefully you may use a ratchet, This will allow you the now use screwdriver between caliper and pads to move the caliper and push the cylinder all the way in. take caliper slide bolts off and remove the caliper, change the pads ( you have to remove the spring piece on front side on the caliper( to the fixed once you would remove to change the rotor), anyway put in new pads. and reverse the order. I then went in car and pushed on braes to set the pads and then re-tightened the torx shaft on the electric adjusting piston. and backed off a little so it wasn't tight and replaced the black electric actuator . and put the assembly back on. and tightened the 2 screws probably no more than 5 or 6 ft pounds since the electric case was plastic with small steel inserts where the bolts tighten. assembled everything else and was done. the only challenge to this type of rear brakes is the extra piece related to either electric parking brake or perhaps with the auto-braking feature for reverse. don't exactly know when it is actuated. but would think it is the electric parking brake. Dealer wanted over $250 to change the rear pads. I think the new ceramic pads cost less than
$30. So I saved a lot. I Hope it doesn't scare you off, but I didn't need a fancy electric tool to reverse the tightening mechanism. But i would try to be as gentle as possible.
 

·
Registered
Joined
·
1,588 Posts
the Rear Automatic Braking uses the VDC (vehicle dynamics control) module, not the parking brake motors... so that shouldn't be a problem for you here (separate systems from the parking brake actuator.

I have seen videos of people doing what you did to retract the piston... it's not in the Field Service Manual (they say to only remove it if the parking brake actuator itself has a problem). There is an o-ring that subaru suggests replacing any time you remove that plastic housing (just as a FYI). I don't think it will really cause you any problems if it was left in place and didn't tear or fall out or anything (you'd notice that).

The torque on those bolts is 5.9 ft lbs (8 NM), so you're right on the money with the amount of force required for those.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #4
the Rear Automatic Braking uses the VDC (vehicle dynamics control) module, not the parking brake motors... so that shouldn't be a problem for you here (separate systems from the parking brake actuator.

I have seen videos of people doing what you did to retract the piston... it's not in the Field Service Manual (they say to only remove it if the parking brake actuator itself has a problem). There is an o-ring that subaru suggests replacing any time you remove that plastic housing (just as a FYI). I don't think it will really cause you any problems if it was left in place and didn't tear or fall out or anything (you'd notice that).

The torque on those bolts is 5.9 ft lbs (8 NM), so you're right on the money with the amount of force required for those.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #5 (Edited)
Thank you for confirmation. The car is only 3 years old, so the o-ring did not come off. In memphis we don't have much use for salt, so very little corrosion. , I would probably have freaked out if the o ring had failed. but the module came off easily and went back on just as easily. If it hadn't I would have stopped and just retightened the cap bolts. getting ready to trade for 2020 XT legacy and didn't want someone to have to immediatly have to put on rear pads. And since i had been told numerous time the legacy and outback shared an inordinate amount of parts, and I couldn't find a legacy sight, I was thankful for the outback one. .
I couldn't find any post to follow on replacing the pads with the electric module. But I finally got a clue somewhere about needing to deal with the electric device, and because i couldn't just retract the cylinder into the caliper. Also I didn't have a tool, or clue if someone could reverse voltage on the actuator to retract, because who knows what voltage it runs on. and would probably be expensive part to replace in addition to having unusable vehicle while trying to get parts.
It just made sense that something had rotated itself tight agains the back side of piston or was part of the piston.
The older saab 99's ( 70's) required you to actually have a tool that had a couple of pins that matched holes in face of caliper cylinder that you rotated to ease the pressure off back side of the cylinder so you could retract it back into caliper to change pads. So either luck or not. I thought there had to be something holding the piston tight, and just took a chance removing the module from back side and found the shaft extremely easy to turn. Saab would adjust itself back within a couple of applications of hand brake and i was taking a chance that the subaru would self adjust quickly as well. but i did not tighten it down quite as tight as it was prior to backing the shaft out hoping it would adjust. It worked immediately thank goodness.

Where do i get a manual that expains all this. or do you have to be a mechanic and be shown how to do this. I think the dealer wanted $260-270 to change the rear pads. I didn't read the "rear" part and just assumed it was front pads, only to take them off and still have 8mm of pad left. I've never had a car that didn't eat front pads at twice the rate of rear.
Do the rear brakes get activated without the front pads in any capacity other than parking? or does the module activate it for something other than parking. I would think using rear brakes for anything other than parking would be very ineffective. since usually front brakes probably do 75% ( or at least much higher percentage than rear) of the stopping. For Saab 96's ( our first expendable Rally car was a 3 cylinder 2 stroke) ( 60'sand V-4 by early 70's) they had disc up front and drum rear brakes , front wheel drive and handbrake on rear wheels , so you could do the famous " SAAB Turn" Cut wheel keeep power on and yank hand brake to flip the car 180 degrees while staying in your lane. not very useful. but cute.
We had 3 cars from memphis in the earl;y days of SCCA pro Rallying. when you didn't have to be rich to enter. and my co-driver and I used old saab 96's because when we tore one up we didn't go broke. Just sounds good that we used to be Pro Rally drivers. It was fun but that was also before factories got involved.
Anyway, I didn't know if anyone would really ever read my story. just hope I didn't lead someone down a path of high dollar to fix a mistake.
Thank you.
David
 

·
Registered
Joined
·
59 Posts
Thank you for these posts! I was doing the brakes (original with 37K miles on them) on my 2017 OB and was getting frustrated that I could not compress the piston on the rear. I was also amazed at how much pad was left on the front brakes after 37K miles; mostly highway but still. Someone commented in the posted video that it might mess up the calibration, since it is being done manually? Anyone tried this.
Thank you,

Semper Fi
 

·
Registered
Joined
·
59 Posts
Well it is not letting me edit my above post. Brakes are working great! Good learning experience. On a side note, I kind of stripped one of the Guide/sliding caliper bolts/pins (7mm Hex). I cannot for the life of me find a part number. Anyone have access to a database that might have that information? Much appreciated

Semper Fi
 
1 - 7 of 7 Posts
Top