DIY Front Brakes for IS350
02-11-07, 06:30 PM
#47
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You obviously never had one stick. I've seen the inside pad less than 1mm away from the backing plate with 5mm of pad on the outside (on a Camry no less.) IMHO, that makes it a fundamentally poor design. I know why the OEMs do it - pure cost. It doesn't make it good.
02-11-07, 07:08 PM
#48
BTW, aren't the IS250 (front and rear) and IS350 (rear) brakes single piston calipers with slider pins?
02-11-07, 07:59 PM
#51
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OK, so they put the Camry style brakes on the 250 and the Supra style brakes on the 350. I wouldn't call that surprising since the 250 is a less expensive car, and they didn't save a boatload of money with the smaller engine. I didn't say they won't stop a car, I said they're an inferior design. They use them because they're cheap, not because they are better. OEMs use the same logic and put drum brakes on the rear of lots of cars. Cheaper. It doesn't mean the car won't stop.
02-11-07, 08:12 PM
#52
OK, so they put the Camry style brakes on the 250 and the Supra style brakes on the 350. I wouldn't call that surprising since the 250 is a less expensive car, and they didn't save a boatload of money with the smaller engine. I didn't say they won't stop a car, I said they're an inferior design. They use them because they're cheap, not because they are better. OEMs use the same logic and put drum brakes on the rear of lots of cars. Cheaper. It doesn't mean the car won't stop.
02-11-07, 08:45 PM
#53
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Sorry, been watching the Winternationals. I'm not arguing functionality or reason for use, just unless you have C6 Z06 (6 piston frt and 4p rear) all Vettes have 2 inboard pistons front and 1 inboard piston rear with 13" rotors front and 12"rear. The point is since there not 4 or 6 piston you have to take at least one slider pin out for a pad change, that's all.
02-11-07, 11:44 PM
#54
And Wolverine is dead on about not needing to pull the caliper. I have done my Supra brakes a number of times, and the IS brakes are nothing special. I also use a C-clamp to retract the pistons because I can progressively retract them at any speed I like (and C-clamps are really cheap.) But pry bars work fine too.
02-12-07, 08:29 AM
#55
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As already mentioned by many others, there's no need to remove the calipers for pad replacement. With the steering wheel turned all the way to one side, you will have enough room to slide the pads out. If the pads are pressed tight, use a screw driver to wiggle it a little and it should free them up.
NEVER NEVER NEVER EVER open the bleeder screw if you are not changing brake fluid. All it does is introducing air into the lines, and if the air is trapped in the ABS system, it's a PITA to get it out. 
Loosen the brake fluid reservior cap and push the brake pistons back in. The fluid will be forced back up into the reservoir and it's totally fine. That's the reason why there's a "MIN" and "MAX" mark on the reservior. They are there to account for the change in fluid level when the pad thickness changes.
As mentioned, if the fluid were never topped off, the fluid level should stay between the MIN/MAX marks and won't overflow. Even if it does, just wipe it off, no big deal.
You should also be opening the bleeder screw on the brake calipers before pushing the piston, this will lessen the force required to push the pistons in and also you shouldn't force the fluid backwards through the system, you could overflow the master cylinder reservoir or possibly damage the internal seals of the braking components, although the later is not likely it is still possible.
Loosen the brake fluid reservior cap and push the brake pistons back in. The fluid will be forced back up into the reservoir and it's totally fine. That's the reason why there's a "MIN" and "MAX" mark on the reservior. They are there to account for the change in fluid level when the pad thickness changes.
As mentioned, if the fluid were never topped off, the fluid level should stay between the MIN/MAX marks and won't overflow. Even if it does, just wipe it off, no big deal.
02-12-07, 09:01 AM
#56
I agree that the bleeders shouldn't be loosened during the pad change, but the pad change should certainly be accompanied by a fluid change. Not that the new pads need new fluid, but very few people change their brake fluid often enough, so it just makes sense to do them at the same time.
02-12-07, 07:07 PM
#57
I agree that the bleeders shouldn't be loosened during the pad change, but the pad change should certainly be accompanied by a fluid change. Not that the new pads need new fluid, but very few people change their brake fluid often enough, so it just makes sense to do them at the same time.
02-12-07, 07:32 PM
#58
Everybody has their own way of doing it, personally I don't believe that I have ever seen a professional mechanic, myself included, push pistons back in without opening the bleeder. It might not hurt to not open the bleeder but it sure is alot easier to push the piston back in and there is also no chance that something will go wrong with forcing the fluid back through the system. I also agree that the fluid should be changed during every brake service, why wait until the brake fluid can't absorb any more water or it has excessive copper content in it and starts destroying the system before you do anything about it.
02-13-07, 03:09 AM
#59
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A lot of professionals are working on flat rate, so almost anything to make the job quicker is fair game. I know how to work like a flat rate mechanic, but I generally don't because I'm not under time pressure like that.
I completely concur with Wai - I won't open the brake system unless I intend to do a fluid refresh. I have also found over the years that it makes a lot of sense to bleed the brakes when new pads are installed, mostly because your worst fluid is in the calipers because they get hot. The other thing about pushing the fluid back: if you push too hard and force it back too fast, you'll cavitate and cause air bubbles. That's why I use C-clamps and a slow retract.
I'd also say if you have speedbleeders installed, opening the bleeders to retract the pads won't be a problem at all. I haven't looked at the bleeders in the IS, but I wouldn't be suprised if they are the same as the Supra.
Finally, I mentioned this once before, if you get air in the ABS valves, you must use the "intelligent tester" to bleed the system. The service manual is explicit on this subject. I would be EXTRA cautious when bleeding the IS350's brakes to avoid having an undriveable car that has to be towed to a dealer to get the brakes bled.
I completely concur with Wai - I won't open the brake system unless I intend to do a fluid refresh. I have also found over the years that it makes a lot of sense to bleed the brakes when new pads are installed, mostly because your worst fluid is in the calipers because they get hot. The other thing about pushing the fluid back: if you push too hard and force it back too fast, you'll cavitate and cause air bubbles. That's why I use C-clamps and a slow retract.
I'd also say if you have speedbleeders installed, opening the bleeders to retract the pads won't be a problem at all. I haven't looked at the bleeders in the IS, but I wouldn't be suprised if they are the same as the Supra.
Finally, I mentioned this once before, if you get air in the ABS valves, you must use the "intelligent tester" to bleed the system. The service manual is explicit on this subject. I would be EXTRA cautious when bleeding the IS350's brakes to avoid having an undriveable car that has to be towed to a dealer to get the brakes bled.
02-13-07, 05:19 PM
#60
I don't work flat rate and IMO it only provokes sub standard repairs, and what harm does it do to flush the system after a brake service even if it isn't required, I do it as a complemenatry service for my customers, perhaps others here aren't so lucky. People here make it sound like the worst thing you could do is breathe on the bleeder, I guess in a sense that is true if you don't UNDERSTAND what it is that you are doing in the first place. FWIW I have never had to use a factory scan tool to bleed an ABS system and I have done them all from Ford to Mercedes and as long as you know what you are doing it's all good, however don't be alarmed if the need arises that I do need the factory scan tool I own them all with the exception of Volvo..but the guy next to me has that one. People, brakes are easy and so is abs, there is no reason to over complicate it by being scared.