Pskhaat
Tourer
Isn't the lock inertia-related? If it is an electrical signal for locking (I can't imagine?) that may make sense.
Poll on total brake failure in 100 series (1 Viewer)
- Thread starter e9999
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
Wondering if anyone knows if these part numbers are interchangeable for the entire master cylindar assembly? 47050-60012 and 47050-60010
I'm Looking at having the entire thing replaced but the 47050-60012 is nearly $300 less expensive and the toyota mechanic said he was not sure if it will fit since my VIN # calls for the 47050-60010.
I'm Looking at having the entire thing replaced but the 47050-60012 is nearly $300 less expensive and the toyota mechanic said he was not sure if it will fit since my VIN # calls for the 47050-60010.
Oh great, so on top of the other potential catastrophic failures (AHC and the early transmissions that seem to like to let go with little warning), the brakes just randomly decide to sh*t the bed in these things, too? I don't even think this was being discussed yet last time I was on the forum. Wonderful.
Last edited:
Pskhaat
Tourer
I've been away a bit myself. What's this? Linkies?
Of course, now I can't find the master thread that collated all the data, but it seems 2000s and some 01s (not sure what the build date run is because I can't find the thread) have like a 4 percent higher overall rate of transmission failure. Certainly not a widespread problem but as I mentioned in another thread, I've never driven a 4 speed of ANY year that feels like it shifts as smoothly as you'd expect. By contrast, every 2003+ with the A750F shifts great. But the really concerning thing about the A343F trans failures is that when they DO go, they tend to just "let go" mid-drive, complete loss of forward momentum from one moment to the next. Something rather unusual and with little advanced warning. This brake issue seems to be exactly the same. What's worse, transmission maintenance, no matter how religious, will not prevent the failure if it's going to happen. I don't like those types of problems.
Is the transmission a known issue on 2000 LX 470?
I'm looking at buying a 2000 LX 470 here in Chicagoland. The one I've got my eye on has 130k original miles and the owner says he had to replace the transmission about 2k miles ago, so at about 128k or so. What's up with the 2000-2001 transmission? If everything else checks out, would that new...
forum.ih8mud.com
CloudCity
LuxCruisers
It's for this reason that I wondered why the assembly is not available as individual parts, or at a much lower price for the assembly. Just doesn't mak snese owing to the numbers made. Do Tundra/4Runner owners experience this failure too?
hoser
SILVER Star
Individual parts are available from Toyota...
Plus the M/C cylinder rebuild kit. And there are new, aftermarket motors available too.
Plus the M/C cylinder rebuild kit. And there are new, aftermarket motors available too.
2001LC
SILVER Star
I've 2000 w/560Km on the clock and brake are fine. Are they a service item, YES! Will it last a million miles and be reliable, YES. Provided properly maintained.
yeah.. i'm thinking.. why do I want to get one of these 16-20 yr old trucks?
Just bought a '98 100 series (200k miles) 2 days ago.
Can't lie, this thread scares me a bit.
I had the vehicle checked out by a mechanic that specializes in Toyota trucks; pointed out a number of problems but said that overall it was mechanically sound. I'm taking it back to the shop to get a few things done on it so I'll be sure to bring up my concern regarding the brakes.
My brakes do seem pretty light / there's a good amount of travel before the brake actually engages. Seems to work fine and I assumed that was just normal ware for a vehicle this old — now I'm wondering if I need to get some work done to the system. Maybe I should start with just bleeding the lines? Then go from there I suppose?
I'm now just imagining coming down Big Bear Mountain in CA after a snowboarding trip in winter when the road is covered in snow, my vehicle just feet away from a massive drop off the cliff, and losing my brakes. Talk about a scary proposition. Guess my best move in that situation if I couldn't stop would be to intentionally smash into a tree to stop the vehicle.... makes a bull bar sound more important now than before
Request: I know there is a lot of information on this thread, but it's spread out between a couple dozen pages from multiple people. A compiled FAQ/how-to regarding the brake system on these would be really useful for new (and old alike) guys coming to the forum to understand what the common issues are, what the symptoms are, where to start in diagnosing, preemptive maintenance tips, and worst case scenario, what we're looking at as far as what needs to be fully replaced to ensure a solid system.
I'm sure it'd be a lot of work for someone who is experienced to compile but it'd be massively appreciated.
Maybe that exists somewhere and I just haven't found it yet.
Can't lie, this thread scares me a bit.
I had the vehicle checked out by a mechanic that specializes in Toyota trucks; pointed out a number of problems but said that overall it was mechanically sound. I'm taking it back to the shop to get a few things done on it so I'll be sure to bring up my concern regarding the brakes.
My brakes do seem pretty light / there's a good amount of travel before the brake actually engages. Seems to work fine and I assumed that was just normal ware for a vehicle this old — now I'm wondering if I need to get some work done to the system. Maybe I should start with just bleeding the lines? Then go from there I suppose?
I'm now just imagining coming down Big Bear Mountain in CA after a snowboarding trip in winter when the road is covered in snow, my vehicle just feet away from a massive drop off the cliff, and losing my brakes. Talk about a scary proposition. Guess my best move in that situation if I couldn't stop would be to intentionally smash into a tree to stop the vehicle.... makes a bull bar sound more important now than before
Request: I know there is a lot of information on this thread, but it's spread out between a couple dozen pages from multiple people. A compiled FAQ/how-to regarding the brake system on these would be really useful for new (and old alike) guys coming to the forum to understand what the common issues are, what the symptoms are, where to start in diagnosing, preemptive maintenance tips, and worst case scenario, what we're looking at as far as what needs to be fully replaced to ensure a solid system.
I'm sure it'd be a lot of work for someone who is experienced to compile but it'd be massively appreciated.
Maybe that exists somewhere and I just haven't found it yet.
Last edited:
I’m not a mechanic and have just recently gone through this process. So this is just me sharing what I wish I had done as preventative maintenance. It seems that when this happens it’s almost always the pump motor. So I wish I would have just replaced the pump motor with a new one. Costs about $600 to $700 + labor. It’s expensive but a lot better than the $3,300 + labor full master assembly replacement. Mine failed and I couldn’t find a reputable shop to replace only the motor which I’m guessing is due to liability. But, I’m betting if nothing has failed and it’s PM you could find a shop to install a new pump motor and accumulator and maybe even the $50 master cylinder rebuild kit.
Anyway, I wish I would have spent the $1000 to do that and have a pretty damn near new breaking system rather than paying more than double that now to replace the whole master cylinder assembly.
FYI, I had my truck completely checked out and baseline 3 months ago with special attention paid to the breaking system. Mechanic found no issues with the breaks. For me, the brakes were perfect until suddenly they no longer worked. I was fortunate to be pulling into my driveway after a long drive when they went out.
Anyway, I wish I would have spent the $1000 to do that and have a pretty damn near new breaking system rather than paying more than double that now to replace the whole master cylinder assembly.
FYI, I had my truck completely checked out and baseline 3 months ago with special attention paid to the breaking system. Mechanic found no issues with the breaks. For me, the brakes were perfect until suddenly they no longer worked. I was fortunate to be pulling into my driveway after a long drive when they went out.
This is crazy.. looked up 4runner forum and there are many reports of the same issue.. Someone mentioned above that these yota trucks all use the same brake system, so it definitely looks like a design deficiency.. What BS!
Nope, no modern toyota 4x4s for me anymore!
Whatever superlatives associated with these trucks are fully diminished by the possibility of the brakes failing suddenly.
Nope, no modern toyota 4x4s for me anymore!
Whatever superlatives associated with these trucks are fully diminished by the possibility of the brakes failing suddenly.
Last edited:
2001LC
SILVER Star
This issues is so over blown.
First we get audible alarm and lights on dash, if given pressure is not reached. Pay attention and stop, do not drive.
Any brake systems on any make or model can and will fail some day. These are moving parts!
Older and some different system today, were/are vacuum assist. That if engine shuts down vacuum lost, assist was/is lost. Same true if vacuum lost for any reason or diaphragm failed. The electrical motor brake assist, solved dead sticking (engine off while driving) brake failure. When either system fails we lose assist, but still have some brakes. But they are very very very pour brakes when trying to stop a heavy moving vehicle without assist, even with all the foot pedal pressure one can muster up.
Proper maintenance is key. This includes not over fill reservoir. Which so many well intending shad tree and certified mechanics and tech are doing. I see this in 50% of 100 and 200 series I inspect.
I've developed an inspection that can help give early warn of pump failure. Thanks in part to those that have shipped me their broken brake master parts (Thank you all). It's based on anecdotal evidence, that if brake booster motor control wire has any corrosion on them which includes nuts or screws. Then they be replaced and motors commutator inspected at that time.
I'm finding resistance of that ~$200 to $300 wire goes up from .5 new to .6 or .07. That anytime I find commutator has worn thought, wire is corroded and resistance is up.
Booster motor is not only reason for brake failure. But is the most common that presumably good PM has been missing. It gives little to no warning in many cases until last few pump of brake pedal.
First we get audible alarm and lights on dash, if given pressure is not reached. Pay attention and stop, do not drive.
Any brake systems on any make or model can and will fail some day. These are moving parts!
Older and some different system today, were/are vacuum assist. That if engine shuts down vacuum lost, assist was/is lost. Same true if vacuum lost for any reason or diaphragm failed. The electrical motor brake assist, solved dead sticking (engine off while driving) brake failure. When either system fails we lose assist, but still have some brakes. But they are very very very pour brakes when trying to stop a heavy moving vehicle without assist, even with all the foot pedal pressure one can muster up.
Proper maintenance is key. This includes not over fill reservoir. Which so many well intending shad tree and certified mechanics and tech are doing. I see this in 50% of 100 and 200 series I inspect.
I've developed an inspection that can help give early warn of pump failure. Thanks in part to those that have shipped me their broken brake master parts (Thank you all). It's based on anecdotal evidence, that if brake booster motor control wire has any corrosion on them which includes nuts or screws. Then they be replaced and motors commutator inspected at that time.
I'm finding resistance of that ~$200 to $300 wire goes up from .5 new to .6 or .07. That anytime I find commutator has worn thought, wire is corroded and resistance is up.
Booster motor is not only reason for brake failure. But is the most common that presumably good PM has been missing. It gives little to no warning in many cases until last few pump of brake pedal.
Thanks for that. I'll bring this suggestion up next time I speak with my mechanic and go from there.
Thanks for that. I'll keep all of that in mind and try to do some inspection of those areas.
I'm with ya that it's a system that can fail like anything else; it just seems that on this forum alone there is a large number of people consistently reporting these types of failures. It's not going to stop me from driving Toyota trucks — but this thread has definitely put it into my head that I can't just "set it and forget it" regarding these brake systems.
The repair costs alone on this system are just staggering. But I guess I knew what I was getting into (parts for these vehicles ain't cheap).
Good thing I bought this as just a secondary toy vehicle (daily driver is a 2000 Toyota Solara)
Last edited:
2001LC
SILVER Star
I hope it helps.
We only drive 100 and 200 series in my home. We feel safer in them, than in any other vehicle. We've have no more worries with brakes than with and vehicles we ever owned or driven.
We only drive 100 and 200 series in my home. We feel safer in them, than in any other vehicle. We've have no more worries with brakes than with and vehicles we ever owned or driven.
- Thread starter
- #478
Issue overblown or not, one major conclusion of this discussion seems to me to be the fact that we -and especially our co-drivers- need to be very aware of the necessity to stop immediately -as in within seconds- driving the vehicle if christmas tree lights come on suddenly on the dash; as it could literally be a matter of losing just about all braking capability in the immediate future. Which on mountain terrain could be fatal. So, no dismissing or poo-pooing the lights with this one. Fortunately, anecdotal evidence above suggests IIRC that if you do react quickly, you can indeed still stop the vehicle, which is obviously a big deal. So, do be sure to remind your better half etc.
Also, one thing that I find puzzling is that the stats suggest that this problem is not correlated with miles as in usage wear. Very odd.
Also, one thing that I find puzzling is that the stats suggest that this problem is not correlated with miles as in usage wear. Very odd.
This is why a well working eBrake is a must, they usually like to seize and rust up so make sure to inspect it and use it regularly to ensure proper engagement. Gotta train yourself and others who drives the car to use the ebrake if the primary brakes fail. Put truck in neutral and pull hard on the eBrake
2001LC
SILVER Star
@e9999 I couldn't agree more.
As for "correlated with miles as in usage wear::
Miles driven or environment, does not seem to be much of a factor.
But condition of control brake wire does seem to have direct relation.
I inspect for this routinely now. If I find corroded control wire, I recommend R&R wire and inspecting booster motor.
Wire may also effect the electronics in ABS unit on side of master. The ABS failure typically just shuts down ABS braking override
Pricey little wire on bottom of black ABS unit of side of master going under it to booster motor
As for "correlated with miles as in usage wear::
Miles driven or environment, does not seem to be much of a factor.
But condition of control brake wire does seem to have direct relation.
I inspect for this routinely now. If I find corroded control wire, I recommend R&R wire and inspecting booster motor.
Wire may also effect the electronics in ABS unit on side of master. The ABS failure typically just shuts down ABS braking override
Pricey little wire on bottom of black ABS unit of side of master going under it to booster motor
