Need for continued brake slider maintenance

i tell this to everyone i run into. it seems, even though the 5k services include brake examinations, the dealers are blowing this off and charging toyota anyway. owners need to be proactive, demand to see wheels off and brake operation at these service intervals.

 

Ted, did you notice an unusually low mpg (or did your mpg go up after the fix)?
Are your glides unusually short compared to your pulses?
Do you usually step on the parking brakes when you park?

Just trying to figure for the sake of the rest of here if there are indications this is happening, ie. low mpg, bad parking habits, etc.

Thanks!

 

^ Something simple you can do is immediately after a drive feel the discs, see how warm they are. They can be a bit warm, normally, but if one is markedly hotter could be be pins needing lube, or piston not releasing properly.

 

I really wouldn't recommend that, i nearly burned my fingers off making that mistake once... and it was in the middle of winter and i thought that would have made the difference.

The problem is, the last thing you do before you jump out the car is to brake. Unless you have 5 to 10 minutes to waste standing around waiting until it cools chances are your gonna hurt yourself.

 

How about using one of those infra-red gun-shaped heat sensor things to measure rotor temps? No contact with hand that way, and mine has the laser pointer to help aim it at a specific part. (I bought mine in Germany but Amazon has several models for $20 or less) Has anyone tried this?

 

If you want to be extra cautious, just place your hand against the hub. Also, heat radiates: as long as you bring your hand up slowly, just tap the metal at first, no problems.

 

Depending on the ambient temperature, how hard and long the brakes were applied, front or rear rotor, etc., rotor temperatures can range from 100 to 400 degrees F., and higher if there is a brake problem. An infrared non-contact thermometer is the surest and safe way to check the temperature of a brake rotor. They used to be expensive, but now you can get a good one really cheap as Robert mentions above. You can also use it to diagnose other problems, such as a miss or non-firing cylinder which will have a cooler exhaust pipe than the other cylinders. NEVER touch a hot rotor with any part of your body, unless you didn't learn the hot stove lesson as child and only learn by making mistakes.

 

I have touched the rotors of my Prius a few times when I parked in the garage and they were just lukewarm at the hottest. Mind you, if I lived at the bottom of a long hill, they would probably be hot. However, I have never ever burned myself (not even close) when I touched the rotors on this car. On the previous cars I had, I wouldn't dare.

Regarding the slider maintenance, my best buddy works at a Toyota dealership. He said they almost never service them during brake jobs. Just new pads in, use a flashlight for a visual inspection and way you go. It's all about speed and making the most cash for them. He gives me the VIP treatment and checks everything properly but for the average customer, none of the techs really go above and beyond from what I hear.

 

I will agree with the OP on this string. It would be best to be proactive on the sliders on the Prius braking system. The Gen II we had experienced the issue brought up in this string. Sliders were dry which caused the inboard pads to wear down to nothing and also prematurely wore rotors. Between the rust pitting from the salt air in Florida where the car originated from to the dry sliders, we ended up replacing both rotors, lubing the slide pins, new pads and re assemble everything. Total cost my dime from Toyota - IIRC 900 to 1200 US That was a couple of years ago. Documented here on PC.

Peace Everyone.

Ron (dorunron)

 

This a very neglected area. Almost no one does it. I just recently had grinding noise in my RAV4, checked the brakes and there was uneven pad wear and almost dry slide pins with some wear. At only 50,000 miles. Granted, brakes are used at lot in RAV4, especially with city driving and towing. Cleaned and lubed but still some noise. Will probably have to replace the slide pins soon. I'll check my prius at 50,000 miles. I'm a bit intimidated by the funky rear brake in prius though.

 

The need to service and lubricate Prius brake slide pins, especially on the rear, should be well known at this point. There have been numerous reports of rear brakes needing to be replaced prematurely because they failed due to dry slide pins. Problem is that people think Prius brakes don't need to be serviced which is a costly mistake when they fail prematurely and need to be replaced. Servicing brakes costs $10.00 if you do it yourself, or $100.00 if you pay to have it done, compared with $500.00 to $1000.00 to replace them. Properly serviced Prius brakes should last 150,000 miles. If neglected, reports indicate they tend to fail in the 20,000 to 50,000 mile range.

See the below thread for information about the problem and how to perform the service.

Brake Caliper Slide Pin Cleaning and Lubrication | PriusChat

 

Besides pin lube, on the rear brakes there's the parking brake mechanism, and ensuring piston's cross pattern orientation is done right is a bit of a black art. I suspect misalignment of this pattern is a factor in some uneven wear, and drag. You want to make sure the cross pattern straddles the pin on back of inside pad, and that pad is firmly pressed against the piston, prior to using the parking brake, post assembly. I believe that can be accomplished, by first carefully reassembling in correct orientation, completing reassembly and then pumping the brake pedal repeatedly, to build up pressure. Maybe even going for a drive, really using the brake, before first applying the parking brake. You don't want that cross pattern to rotate on the pad, run the cross arm up onto the pin.

This is one instance where drum brakes in the rear might be less trouble prone.

 

I agree. Way too complicated and failure prone. The existing rear brake TSB proves that the parts were not designed right in the first place.

 

makes one wonder if we were better off with the drums. 2004 and 2008, both with over 100k and no brake issues.

 

This is our first rear disc car and so far they've been more problem. After finding uneven wear I threw in the towel, installed new pads. Front pads are more tried and true. Rear drums need very little maintenance in my experience. Maybe the trade off is a bit less brake power? But I can live with that.

Main thing seems to be drums are less sexy.

 

I have rear disc brakes in RAV4, but they are much simpler design with parking brake being mini drum inside the rotor hat. Same with my previous Subaru.

 

I have had rear disk brakes on all my cars since 1990, Lincoln, Ford, GM and Toyota, and they were are trouble-free. The big difference between the 2010 Prius and my other cars with rear disk brakes is that the Prius components are very light weight and don't tolerate abuse or lack of maintenance. Prius rotors are very thin. The calipers are made of a lightweight material. If the slide pin lubrication fails or the sliding surfaces get dirty or corroded causing the pads to drag, the lightweight rotor overheats and quickly destroys the pads and calipers. That, combined with a hybrid car where the rear brakes work harder than the rear brakes on a conventional front-drive car, due to regenerative braking on the front and a heavy hybrid battery in the rear, and you have a recipe for failure. It's just another part of car that has been made lighter to save weight and increase fuel economy, resulting in it being less durable and requiring more maintenance. Problem is Toyota does not call for this needed maintenance in their maintenance schedule and people think it is not required. It is imperative that the rear brakes be scrupulously maintained if you want to avoid costly repairs.

That said, I still prefer disk brakes over drums because of their better stopping ability. Disk brakes require no adjustment and give you the shortest stopping distance. Rear drum brakes lose their adjustment and cause the front disk brakes on a disk/drum car to do more work and wear out sooner. People with rear drums also tend to not get them adjusted or serviced as well. When not serviced or out of adjustment rear drums don't fail, they actually last longer because they are doing less work, causing the front disks to do more work, wear out sooner, and stopping distances to increase.

 

are the '14's or '15's any better?