2 Gen Caliper Rebuild

2009 with 180k miles.
Outer seals had tears and calipers seemed slightly sticking/hanging up/pistons not retracting properly. Rebuild solved all that. Pass side was worse on disassembly.

Need:
Toyota cylinder kit #

$23 04478-04050 Toyota Caliper Kit - 04478-04050

04478-04050 based on my VIN ($20)
Dot 3-4 brake fluid used Val Syn
3M gray and maroon scrub pads
220 grit sandpaper
Brake cleaner spray
Paper Towels
Cardboard to catch all your mess and/or a pan
Breaker bar 1/2" and ratchet
Torque wrench and 21mm socket for lugs
1/2" drive 17mm and 14mm for caliper removal and disassembly
10mm brake line wrench
2 small rubber caps 7/32 or smaller for open brake lines (don't forget these or a leaking mess)
Large screwdriver to pry out pistons and very small one to pull inner seal out of groove
Brake bleeder setup or a section of small hose and bottle or cup
Small wire brush
Caliper paint if you want and tape

1. After your truck is properly supported safely and wheels removed, break loose the 17mm and 14mm bolts that hold the 2 caliper halfs together while on vehicle. Hard to hold later.
2. Clean any crap behind the brake line fitting on the caliper and then carefully loosen with the 10mm brake line wrench - do not mangle the head.
3. Remove the two 17mm caliper to truck bolts and complete the brake line hardline removal so caliper can be taken off vehicle - use the small rubber cap to cover the dripping breed line. Now you see the use of cardboard and/or pan. Watch your master cylinder and do NOT run it dry or air will get into the ABS - with the lid on and rubber caps on the open lines you will have no problems.
4. With the caliper on the bench split it apart but save the rubber o-ring (single sided on mine) as the kit does not include a new one to use on reassembly).
5. Drain remaining fluid out of calipers and then pry/pop the outer seal off the 4 pistons.
6. You can use air to blow the pistons out but hard to control so I used a large screwdriver to simply pry them out under the top lip going from side to side and using a socket for leverage as they came out. 2 screwdrivers at same time is not in my dexterity range.
7. After removing the pistons clean them with the finer gray 3m pad and do the caliper body also. I had to get in there with a maroon pad first as finish was rough in the bore finishing with gray. Tops of pistons can be cleaned with 220 grit then the 3m pads but only the upper or outer area and make sure you get off any burrs so the outer seal is not cut on install.
8. Finish the caliper bore by removing the in bore in groove rubber seal carefully with a small screwdriver or pick. Then spray all with brake cleaner and inspect. Make sure you spray the internal passages in the caliper ensuring they are clean.
9. If you paint your calipers at this point when disassembled you will need to tape off the internal bores and machined half surfaces and remember that the paint takes a few hours to dry to reassemble!! Or you can wait to the end and do it as to reinstall on truck after paint is only a short wait. Up to you how perfect you are on looks.
10. Reassembly put in the inner bore/piston seals and then lube with clean brake fluid. Dip the pistons machined outer surface in clean fluid and insert in bore. I used my palm to push down and they popped into the bore. Push down till you see the top piston seal groove flush with the top of the bore. Then put on the outer seal by stretching around the piston and setting into piston groove. Next push the outer seals lip down flat around the caliper ridge. Then install the metal seat retaining ring making sure it and seal are flush with caliper body surface. The kit includes rubber grease to lube the outer seals.
11. With the mounting half caliper surfaces clean reinstall the small seal in the depression in the half (lubed with brake fluid) and put together and retighten the 4 bolts but not so tight you stretch/break them as no torques found.
12. Put the completed calipers back on vehicle carefully reinserting and screwing the metal brake line back onto the caliper (careful to align the threads so not to crossthread or strip the brake line nut).
13. Afer install I opened the top bleeder and gravity fed the caliper then shut off and bled the old fashioned way with 2 people and the bleeder screw method never putting the ignition key in or turning so as not to lock the ABS system out and requiring a dealer tow and their scan tool. There are many many opinions on this but old way works. After pedal firms up then time for the key to ON and hear the ABS pump kick on and pressurize. Topped off master cylinder to Full line.
14. Test drive and a few hard stops then a panic with ABS and all perfect and straight. I have Powerstop drilled/slotted with z36 pads. Second set I have installed. Again, many opinions and you decide for yourself.
15. That's it and there are a few videos out there but my pics may help others. Total time for my old self was 5 hours pulled into garage till finished test drive and cleaned up. I did paint the calipers black and at the start after wheels off repainted the aftermarket black lug nuts as they get beat up by tire shops.

 

Nice! Need to do this soon

 

Well done writeup. The above part is absolutely important.

I attempted this once many years ago, decided it's not for me. It's definitely a cheaper option to replacing with new or rebuilt.

 

plopping a caliper down on a bench, blowing the pistons out with compressed air, and slapping them back In with new lube and O-rings (couple bucks) is too hard?

interesting

did this a year ago during a brake job. Did not take long at all

diy regear = hard
Caliper rebuild = very basic

or maybe it’s better to just neglect rebuilding until the brake fails then spend way more on an incorrectly remanufactured one to have issues

 

It’s something I could do now. 30 years ago, without the knowledge I have now, it gave me a hard time.

I’ve rebuilt hundreds of hydraulic cylinders and ball valves so if I chose to, I could do it. Seeing how I have too much money and not enough time, I’d still buy new, not rebuilt.

 

hello my friend. I see you add some value to certain threads but seem to talk down and provide a certain demeanor to other topics. This is one of those. Rebuilding calipers while I agree certainly isn’t hard isn’t beyond most peoples’ skill sets, however most people don’t have the time to fuck with cheap seals and hours to rebuild and would rather just get a quality rebuilt product (myself included). If you have the time to do it great for you, and I’d pay you for your time. Most people don’t, and would rather have a spare to swap out over a weekend, and keep on trucking on without the down time

 

i can tell you I smelled some fire and had some shitty moments with my one ton, bought the rebuilt calipers and “new” rotors from powerstop

https://www.tacomaworld.com/threads...-pig-build-and-bs.571427/page-5#post-25888186


Bottom line is that no matter who you trust to make brakes for you, at some point they are all made from a similar standard, albeit maybe better standards, and you can expect those better products to last longer. Brakes are a wear item and you should expect them to fail at some point. Not many folks have the time to rebuild their calipers after they fail as the vehicle is down already at that point.

 

Many remanufacturers buy calipers from junkyards and toss them into abrasive bead tumblers, stripping too much material off, and stripping the precious zinc coating off which acts as both a lubricant (on a smooth bore) and as a rust preventative, before painting the outside to look cool

It takes literally seconds to squeeze a blow gun into a caliper hole to pop the pistons out while wearing ear protection and a block of wood inside to catch the piston from flying across the room or hitting your hand, and safety glasses to avoid brake fluid in your eye. It can create a cloud of mist. Another option is grease gun.

Caliper removal you would be doing to replace it anyway.
Bleeding fluid post-repair, you would be doing anyway. Which is the most time consuming part.

Seal kits are about $7 from the dealer, for high quality genuine parts. This has always been the case for any automotive brand. All automakers use the same suppliers like Ate, TRW-Girling, Brembo, and so on. A square-cut caliper seal is just a piece of rubber.
It's not hard to take the old seal out with a pick tool, that most people have. It's not hard to shove the new one into the bore with your hands. Nor to install the dust boots, which have a very simple design compared to other cars.

If somebody wants to risk buying a poor quality "remanufactured" part, and spend a lot more in the process, that's up to them

If you rebuild a decent caliper, then it probably works. If it's remanufactured, there's a chance it won't. Eric @ PMB Performance (known for restoring old Porsche calipers) does remanufacturing properly, including zinc coating. Better than NAPA.
The only drawback is you have to catch it before it's too late. If it looks decent inside and has 130k miles, no problem. If it's 1mil miles found at the bottom of the ocean, it's not.
It's not recommended to abrade the bore area either, at least when it comes to a hone.

There are some high quality caliper greases out there. By applying it to the bore and seal (sometimes the kit comes with the grease packet and instructions), you know you're protected. You know you have a smooth film lubricating the piston, and keeping the seal at least somewhat hydrated. Acting as a barrier between the outside moisture that wants to get in, and the corrosive brake fluid inside.
Otherwise, you don't know if it has the grease. At least some people rebuild theirs lubing with DOT4 instead of grease. But I'd hope a reman company would use grease if anything from a standpoint of easing + speeding up installation and preventing scratches during piston insertion

Spare set is another option, junkyard or otherwise. Bought a set for $60 before then sold the like-new Akebono ceramic pads that came in them (different car) for about $50