Seized brake caliper pin in rear left tire. Quoted $1500 - questions

You live in a colder climate so it doesn't surprise me that you are in this situation. When it comes to brakes, safety first! They want to make sure your repair is done right the first time. You could do this all yourself, but I will tell you that fixing brakes on a hybrid is ALOT different than your standard car. There is an entire section in Priuschat on how to do this if you want to tackle it on your own. As for buying parts, this too should be done carefully! Too many aftermarket parts that don't work! I know it sounds like a lot of money, but its really important to have your brakes done right the first time.

 

I'll be a dissenting voice. There are some things about brakes on a hybrid that will seem different if someone has only messed with older conventional car brakes before. (Even some of those things are probably more like "different in a modern car with computerized brakes" than they are "different because it's a hybrid".)

Changing pads (and, if needed, rotors) is pretty much like changing pads and rotors on anything. In a Gen 3 liftback, the rear calipers combine the parking brake function, and need a special little tool to rotate the piston while pressing it back in. Every auto parts place has the little tool.

The car's computerized brakes have a little self test they do a minute and a half after powering down the car. Make sure you don't have the brakes apart then, and don't power up the car while they're apart.

If the brake hydraulic system gets opened, then a scan tool with the brake bleeding feature is non-optional for properly bleeding the brakes. Repairs you make without opening the hydraulic system don't require that.

The caliper slide pins attach a caliper part (which is movable, and has the piston) to a bracket part (which attaches to the car, and holds the brake pads). At each of the two pins, a small bolt holds the caliper to the pins.

Remove those bolts and the caliper lifts right off. Have some wire or string to suspend it so you don't hang it by the rubber hose. Now you have the bracket, with the pins in it. Maybe they're stuck and hard to work loose. Maybe they're really stuck and you can't get them loose. If so, just change the bracket. It's available separately, around $100 last I checked, that's if you don't get one from salvage. If the two bolts holding the caliper to the pins won't come off, break them off. Use spare change to buy new bolts with your new pins.

Put two nice shiny new slide pins (with the glycol-lithium red rubber grease) in the replacement bracket. Secure the bracket (proper torques are in the repair manual). I would go all out and spend the $20 or so on the new "fitting kit" (little springy clips that go in the bracket to hold the pads), and whatever Toyota's asking for a set of rear pads these days, I doubt it's over $100. I wouldn't personally go third-party on the pads, I've read posts here with people having to grind on them to make them fit. Toyota makes them the right size right in the box, saves you time and hassle. Maybe blow the $20 on shiny new shims too.

Push the caliper piston back in (with the rotating tool) to fit over the new pads, attach it to the new pins with the (possibly new) bolts and call it a day.

Notice I didn't say replace the caliper. Now, if you notice the piston is really hard to squeeze back in, or if the rubber boot is torn and salt water got in and there's rust around the piston, that's a different story, could call for a caliper. So check that carefully while you're looking. If you change the caliper, you'd better have a scan tool for doing the bleeding.

By the way, there's a rebuild rubber kit available for the calipers. Way cheaper than replacement calipers, and, if needed, your original calipers properly rebuilt will probably still have a quality edge over parts-store specials. But whether you replace or rebuild, that's opening the hydraulics, so calls for bleeding afterward. If the caliper is still ok, just put it back on, after solving the stuck pins/bracket issue. No opened hydraulics, no bleeding.

If you want to do the other side to, go ahead; when you buy pads, or fitting kits, or shims, those are always sets for both sides.

Have you been adding those numbers up? I'm not at $1500 yet, am I?

Do you want to do the fronts as well? Go take a look and see how they are. The service writer wants to worry you because they're down to 4 mm. They're born 10 mm and the service limit is 1 mm. How long has it taken them to get from 10 to 4?

But you can easily check them ... sometimes they're not all worn the same, and you'll find one of them that's closer to worn out. Of course you have to set your schedule by the worst one.

Rotors, you can measure the thickness, and judge how gouged up they are. I did replace my rears not long ago, not because they were anywhere near minimum thickness, but because they had become rusty rough and were eating the pads away. I did go third party on rotors; Toyota's price strikes me as high for a part whose whole job is to be cast iron and round and flat. Other vendors can make those. I walked into my local brick and mortar job shop and walked out with their house brand, around $26 each.

There's not a lot here you and your car-DIY friend can't figure out.

 

They do Porsche owners like that

 

If you DIY, and really want to avoid the car activating something that ends up pushing a piston out of a caliper, disconnect the 12 volt neg cable before you start.

Also, when everything is back together, pump brake pedal multiple times, firm up the pedal, before reconnecting the 12 volt. This will hopefully avoid the car detecting excessive brake pedal, throwing a code.

regarding 4 mm remaining on front pads, I’m on the fence. If they show you the pads you’d probably cave and say replace. 4 mm technically sounds like a lot more than 1 mm, but do you want that pending? And there is upside to having everything balanced, new.

If you DIY be careful with rear piston orientation, after screwing it in; orientation is important, to avoid uneven pad bearing, drag. One of the links in my signature is on that. (On a phone turn it landscape to see signature.)

Repair Manual brake information attached, in aforementioned signature link.

 

Did you buy Toyota OEM parts?