Rear Brake Caliper Removal

[GrayES300]

I noticed that on my last replacement of my rear brake pads, I couldn't get the rear calipers to open fully to accept the new pads. I think they might be warped or frozen. I was going to try a brake caliper spreader to see if that frees it up. Right now I use a C-clamp when changing pads. If the spreader fails, I will need new calipers I think. How do they come off? I only saw one bolt on the back. When I remove it, is the front supposed to slide off a hidden pin? The caliper does not rotate upward easily and won't slide off as far as I can tell. Am I doing this right? I don't want to force anything and break it. Any thoughts or step-by-step guides would be greatly appreciated. By the way, I have a 2001 ES300.

[camlex]

http://www.autozone.com/servlet/UiBroker?F...23d8013f934.jsp

Hope that helps.

Thanks,

[GrayES300]

This does help a little. See figure 2...The bottom shows the bolt that holds the front of the caliper on. On the top, there is no bolt. The front calipers have 2 bolts. Is the front of the rear caliper supposed to slide off when the bottom bolt is removed? Does the fact that mine won't indicate that it needs replacing?

Thanks for the help.

[steviej]

If I remember correctly (been 2 months since I did mine) there is one bolt on the rear caliper. The other is a post. Remove the bolt, pivot the caliper up and then it slides off the post.

steviej

[GrayES300]

After removing the bolt, The caliper barely swings up. I have to use a pry bar or large screwdriver to force it up high enough to remove the pads. I think the pin must be bent somehow. The side with the piston goes all the way in and accepts the new pad, the opposite side won't open enough to get it on. Do you think I need a new caliper or is there a way of fixing this?

[tgsantini61]

GrayES300, I know this post is several years old but how did you resolve this problem? I have the exact same issue and it doesn't look like anyone replied with a valid response. The rear calipers on my 2005 ES330 do not allow for the inner brake pad to be replaced.

[Phast Phil]

I noticed the same problem on my 2002 ES300.  The new pads will fit but you'll need to: 1) compress the caliper piston fully back into the cylinder (use an inexpensive brake caliper tool or a ratchet clamp), and; 2) hand squeeze the caliper and caliper bracket together to allow the caliper to slide over the pads (there is a soft rubber boot on the upper guide pin that sometimes needs some "squeezing" to properly align the caliper).  Also, be sure to clean and lube up both guide pins with some silicon grease before reassembling.  I'd noticed that the upper guide pin and hole had frozen together due to rust build-up.  It was hell getting the caliper off (once you swing the caliper up it should just slide right off - mine would neither swing nor slide).  The upper guide pin is actually an allen bolt and can be removed for cleaning.   

[parkerd]

The problem is that the Brake Cylinder Assembly will not slide off the Cylinder Slide Pin.  I have exactly that same problem on a 2004 ES330. 

With the Brake Cylinder Assembly rotated up to clear the Brake Cylinder Mount, I used a zip gun on the Brake Cylinder Assembly right by the Cylinder Pin but the Brake Cylinder Assembly does not slide off.  Same story on both sides. 

I want to clean and grease the Cylinder Slide Pin as well as the Cylinder Slide Bolt (Toyota calls this bolt a "Cylinder Slide Pin").

The brakes can't work if the Brake Cylinder Assembly does not slide freely on these two pins. 

[gbhrps]

parkerd,

Its been a few years since we traded our 2004 ES330, but I've had those rear calipers and caliper mounts off the that car 5 or 6 times for cleaning and relubing, without any issues. Yeah, its a strange setup, that top slide pin that stays with the caliper mount, and doesn't usually ever get removed like the bottom slide pin, and most other car setups.

I would suggest that you remove the brake fluid line from the caliper, remove the caliper mount, and place it in a vice where you can see what you're doing much better, and get some leverage at removing the caliper and that slide pin. Its too long ago for me to remember, but I seem to recall that the end of that upper slide pin had a smaller octagon head under the plastic cap? You put a wrench on it? Or maybe it takes a larger allen key inserted into its end? Too long ago for me to remember.

If so, it should give you something to get a wrench on to undo it from the caliper mount. If its rusted in place, you might try hitting its threaded section in the caliper mount with an ordinary propane torch setup, but using a yellow tank of MAP gas (burns much hotter) rather than propane. It should expand the metals enough to break the rust free. I've had good success with this method in the past.

If not, twist it off, drill out the pin threaded section and retap the caliper mount, and buy a new slide pin from Lexus (cause I'm pretty sure you can't get one from any other source). Good Luck!

[parkerd]

Thank you. 

However, my setup does not have that dust boot (plug) in an open hole in the casting.  In my case it is a blind hole, the hole that receives the Cylinder Slide Pin does not go all the way through. 

The Cylinder Assembly was frozen when I got to it, it did not rotate freely on the Cylinder Slide Pin.  It was probably not greased from the factory.  From the comments of others here, it seems quality control broke down, bad report for otherwise premier Lexus quality.

The solution was a five pound hammer and punch.

1. Remove the brake assembly - the two mounting bolts with the 14mm head.

2. Remove the brake rotor

3. Reinstall the brake assembly - bolts tight, don't exceed 45 ft-lbs. torque.

4. Position the punch just over the dust boot seal lip on the Cylinder Assembly, as close to the frozen Cylinder Slide Pin as you can get.  The hit will not be ideal, it is impossible to get a straight shot at it, but as close to parallel with the Cylinder Slide Pin as you can get is good enough.

5.  Using the heavy punch and small sledge hammer, knock the Brake Cylinder Assy. off the Cylinder Slide Pin.  It will not come off gracefully, you will have to fight for every fraction of an inch, but take care not to damage the seal lip, but in about ten hits it should be off the pin!

6.  Once off, remove the Dust Boot.

7. With a spiral wire brush, drill, and brake cleaner, clean rust from the hole.

8.  Using a wire wheel (preferable and a lot faster) knock all the rust - right back to bright metal or conversion coating) from the Cylinder Slide Pin (both of my pins were loose and unscrewed by hand after I knocked the Cylinder Assy. off the Slide Pin;  otherwise, use an 8mm or 5/16" Allen wrench to remove it).

9.  Put grease (disk brake grease if you have it, wheel bearing grease if you don't) in the Slide Pin holes:  I used a soda straw, pencil will work, smear the grease all around the walls of the hole.

10. Screw the cleaned Slide Pins back into the Disk Brake Cylinder Mounting and torque to 29 ft-lbs (look at the diagram above, Toyota/Lexus lists the bolt size and torque right next in the part callout, quality documentation unheard of among American manufacturers)

11.  Remove the Brake Cylinder Mounting, install the Rotor, install the Brake Cylinder Mounting and torque the mounting bolts to 46 ft-lbs.

12. Clean all grease from your hands, change gloves, whatever - DO NOT ALLOW GREASE ON THE PADS OR THE ROTOR.

13.  Reassemble the brakes.

13.  Pump the brake pedal to ensure you have a firm pedal before you head out to enjoy your Lexus again!  If you loosened a brake line or the bleed valve, you may need to bleed the system.  At the very least you will have to pump the pistons into contact with the pads and the pads to the rotor.  ( I always crack the bleed valve and catch the brake fluid when I press the brake piston back into the cylinder.  This flushes the brake lines and master cylinder a little bit.  If you flush the brake hydraulic system as I do, be sure to top off the brake reservoir too and if you screwed up and allowed air into a slave cylinder, you get to bleed it.  Be nice to your wife and you will always have help pumping the brake pedal while you bleed the system).

If I left anything out, you do that too.  If you can stop safely, you have time to figure out how to get going again.