2007 Prius Brake Maintenance Intervals

you don't need to change brake pads or rotors preemptively

do the inspections at suggested intervals

lube the caliper slide pins as needed.

learn the pad thickness spec and keep an eye on them.

consider a more aggressive brake fluid change interval

any good shop can work on prius brakes, but you have to be sure they're good. if they just tackle them like chevy brakes, you'll have issues.

 

Inspect the brake front disc pads and rear drum shoes so that you do not have to guess about their condition. The minimum spec is 1 mm thickness; a new brake pad has 11 mm thickness while a new brake shoe has 4 mm thickness.

I would not trust brake repair to an independent unless it specialized in Toyota hybrids, since, for example, it is necessary to have access to Toyota Techstream software to flush brake fluid.

 

any conscientious mech can measure the pad thickness, but you might as well have a talk with them to find out what they can do in the future as well.

 

You can see the front axle outside pads by looking through the holes in the wheels. For a complete inspection it is necessary to remove the front tires, then the front axle inside pads can be inspected via the hole in the caliper.

The rear brake inspection requires removing the tires and the brake drums must be removed. Then you can see the brake shoes.

My 2007 has 134K miles on the odometer and I have not done any work on the brake system. The brake pads still have around 40% thickness left.

 

If I'm not mistaken, US second gen is same as third:

Visual inspection every 5k miles or 6 months

Full inspection every 30k miles or tri-yearly.

 

Is that strictly necessary? I just pulled the rubber plug off the rear of the drum, a handy little trick I just learned about.

 

You want to pull the drum. My cheap/quick maintenance with drum brakes, after removing drum, was take the hold down clips off the shoes, then pull them away from the backing plate and put a dab of high-temp grease at the (3 per shoe) contact points. Clearance is limited so you need to be careful, avoid getting grease on the shoe face.

Also blow out the dust and check drum and shoe dims against specs.

M8x1.25 bolts are good to coax a stuck drum off: there's threaded holes in the drum for these.

 

If you are happy with that method, then peace. I do not see how you can inspect the lining on both brake shoes via looking through a tiny hole. It is quite easy to remove the brake drum, worst case is to use two bolts as Mendel suggested to push the drum off the backing plate.

 

Toyota makes a special lube for the drums. Forget the number though. The front pin slide grease is 08887-01206.

 

So I'm curious. If the hole isn't designed for inspection, what is it designed for? Why do mechanics (who I know to be good mechanics) use it for this purpose? If the brakes are self-adjusting, shouldn't one small spot be enough to see the shoe wear?

 

The hole will allow you to see one brake shoe lining at one spot.

A professional mechanic is typically interested in performing a job as quickly as possible to maximize his income.

You can see the wear on one shoe. You cannot see the wear on the other shoe via that hole. So you have to assume that the shoes are wearing evenly.

If you took the trouble to remove the brake drum then you might learn that assumption is invalid. Or you might see that the wheel cylinder is starting to leak brake fluid. Or maybe you would see that the inside of the drum shows abnormal wear.

If you are a conscientious DIYer then maybe you might be willing to invest another 15 minutes per wheel to learn that information since you have accepted responsibility for the vehicle maintenance and you are entrusting the safety of your family to your observations and the quality of your work.

Similarly, with the front disc brakes, you can inspect the thickness of the outer pad via a wheel hole. However you cannot determine the thickness of the inner pad unless you remove the wheel.

You could assume that both pads are wearing evenly. But if you took the trouble to remove the wheel you might see that the inner pad is wearing faster because the caliper slide pins are sticking, thus the caliper piston is exerting more braking force on the inner pad. Or your assumption of even pad wear might be confirmed via the visual inspection.

 

Asking a follow-up question about this intriguing thread. So, based on what I read so far,

1. "Peeking through the hole" is, albeit not comprehensive, still supposed to be a quick-and-easy rear brake inspection method (similar to the "peeking through the wheel" method to the front brake pad).
2. There is even this Prius gen 2 repair manual, page 10, indicating that there shall be 6 oval-like inspection holes at roughly 1, 3, 5, 7, 9, 11 o'clock location.

However, I found only one hole on my Prius 2007 rear hub, and the hole is right at 12 o'clock location. But I don't see how it reveals the thickness of my rear drum brake shoe. Am I missing something or looking at the wrong hole?



FYI, I am the second owner of a Prius 2007 currently at 140K miles and the rear drum brake has never been serviced, at least not in the last 60K miles under my ownership. I'm just trying to see if there is an easier inspection method other than taking the drum off.

 

Those are lube points, not holes, where the shoe edges contact the backing plate. If you take off the spring clips that hold the shoes firmly against the backing plate, you can pull the shoes away from the backing plate and sneak a little dab of grease in at each point.

the above is basically the length and breadth of what I’d typically do as a drum brake service, infrequently at that.

not sure but think that hole you found at 12 o’clock IS for the star adjuster.

 

Manual shoe adjustment. If you pull your parking brake lever up more than a half dozen clicks - you adjust that FIRST; then the brake cable tension. That procedure is for a standard cable parking brake adjustment; if you have auto-parking brakes - then follow OEM procedures.
You'll notice shorter, better braking because the rear brakes will be contributing more, when properly adjusted/calibrated. Shorter travel distances for your rear brake pistons. From my experience, this should be done every 50K miles. While the adjustments should be automatic, in the real world they are usually off by a bit. Some people say that backing the car up about a block while dragging the brakes will force an adjustment- try it, it doesn't. IMHO; manual adjustment always works better.

Hope this helps...

 

In different cars, Toyota has used different types of drum brake adjusters, a "reverse travel" type and a "parking brake" type. The Prius uses the second type, which is why if you try using reverse travel to adjust it, nothing happens.

For the Prius, the self-adjustment depends on you using the parking brake regularly. The adjust mechanism has a kind of ONE-TWO action, where ONE happens every time you put the parking brake on, and TWO happens the first time you step on the foot brake after letting the parking brake off. Each ONE-TWO reduces the lining clearance by a tiny amount, 0.03 mm.

If you aren't in the habit of using the parking brake every time you park, it is possible this just hasn't happened often enough to keep up with brake wear. Assuming the adjusters aren't stuck, you can catch up without even taking anything apart, just by repeating (apply parking brake, release parking brake, apply foot brake, release foot brake) a bunch of times, though bystanders will wonder what you're doing.

If you listen closely enough (in a quiet-enough place), you can hear one faint click on each one of those cycles, until you stop hearing it when the proper adjustment has been reached.

But yes, if they've not been checked for a while, or have been acting out of adjustment for a while, it is worth opening them up for a look, or manually clicking the starwheel through that access hole a few times.

Opening them up for a look is better: you could find the adjusters to be stuck, or even have a tooth or two worn off from being stuck in one place too long. The replacement parts are only a few bucks.