Aftermarket (gasp) Brake booster motors

[Bisho]

So, as I prepare to cross 300k miles, and I overland to remote areas, I've had it on my mind to rebuild my brakes. I don't have any obvious concerns, other than age and miles, but I also don't want to discover a problem coming down Black Bear Pass. @OwnerCS recent brake failure that was solved wedging the truck between two trees certainly has got me thinking about this. I just ordered new rubber hoses and a Master Cylinder rebuild kit from Partsouq. The center hoses were not available so those are Sunsong from Rock Auto.

It seems the most common failure of the brake booster is the motor, which OEM is $800 (from Partsouq), which is ridiculous given you can buy the whole brake booster assembly for $1300. So, I've had it on my mind that I would rebuild the master cylinder ($71 OEM parts) and rebuild the electric motor ($150ish for kit from ebay). Seems like an economical way to get at the wear parts.

What I just discovered: Amazon.com : toyota 4796060010 - https://www.amazon.com/s?k=toyota+4796060010&i=automotive&crid=NRCZ47VB19IT&sprefix=toyota+4796060010%2Cautomotive%2C109&ref=nb_sb_noss

There are now quite a few aftermarket brand new motors available, which seems like a better option than rebuilding mine. You can even get them with the pump assembly for a bit more. Any thoughts from the peanut gallery? I know the purests are going to hate this idea, and it will surely kill me because it isn't Toyota OEM, etc, but I'm really not interested in spending $1300 on a new booster assembly, but I also think it would be prudent to refresh the motor. Does anyone have experience with this route? Suggestions?

 

[SteveH]

Since my booster motor crapped out at 309K miles (literally 500 miles after I bought the truck ) I have been following threads here. I replaced the entire assembly for $1300. All of my parts appeared original (motor, accumulator, MC).

I see that some people on Mud have replaced (individually) the motor, the accumulator, and/or the master cylinder. Some have then had to replace the next part in line that pooped out. I just didn't have great confidence in the Chinese eBay stuff that supposedly fit. You are obviously totally capable of fixing your truck, so that's not an issue (labor-wise). If you can be without your truck for a week or two, that gives you some flexibility in the tear down/analysis/parts ordering process.

I considered buying the aftermarket motor, but didn't know that was 'all I needed' until I tore it down. I didn't want to be 'in there' fixing this brake issue more than once. My wife agreed that brake stuff is kinda important to have working and supported the 'buy once, cry once' approach, so I bought the whole enchilada. YMMV!

Reply #13 in the build thread in my sig line shows the destroyed motor guts.

 

[Bisho]

Since my booster motor crapped out at 309K miles (literally 500 miles after I bought the truck ) I have been following threads here. I replaced the entire assembly for $1300. All of my parts appeared original (motor, accumulator, MC).

I see that some people on Mud have replaced (individually) the motor, the accumulator, and/or the master cylinder. Some have then had to replace the next part in line that pooped out. I just didn't have great confidence in the Chinese eBay stuff that supposedly fit. You are obviously totally capable of fixing your truck, so that's not an issue (labor-wise). If you can be without your truck for a week or two, that gives you some flexibility in the tear down/analysis/parts ordering process.

I considered buying the aftermarket motor, but didn't know that was 'all I needed' until I tore it down. I didn't want to be 'in there' fixing this brake issue more than once. My wife agreed that brake stuff is kinda important to have working and supported the 'buy once, cry once' approach, so I bought the whole enchilada. YMMV!

Reply #13 in the build thread in my sig line shows the destroyed motor guts.

Post #14 in your thread is me

I totally understand in your case not "knowing" what is broken and not wanting to be down chasing parts. I do have the advantage that mine is just fine, but I want to avoid being in the spot you were in on the side of a mountain. Looking at the pics from Amazon/eBay, I'd guess all of these aftermarket motors are built in the same factory and have different distributors.

 

[SteveH]

So, you tracked the whole thing. I took my FJ62 down Black Bear pass last year, and agree, that'd be a lousy place for no brakes. I suspect you are right in thinking that all the Chinese replacement motors are sourced from the same place.

 

[suprarx7nut]

So, as I prepare to cross 300k miles, and I overland to remote areas, I've had it on my mind to rebuild my brakes. I don't have any obvious concerns, other than age and miles, but I also don't want to discover a problem coming down Black Bear Pass. @OwnerCS recent brake failure that was solved wedging the truck between two trees certainly has got me thinking about this. I just ordered new rubber hoses and a Master Cylinder rebuild kit from Partsouq. The center hoses were not available so those are Sunsong from Rock Auto.

It seems the most common failure of the brake booster is the motor, which OEM is $800 (from Partsouq), which is ridiculous given you can buy the whole brake booster assembly for $1300. So, I've had it on my mind that I would rebuild the master cylinder ($71 OEM parts) and rebuild the electric motor ($150ish for kit from ebay). Seems like an economical way to get at the wear parts.

What I just discovered: Amazon.com : toyota 4796060010 - https://www.amazon.com/s?k=toyota+4796060010&i=automotive&crid=NRCZ47VB19IT&sprefix=toyota+4796060010%2Cautomotive%2C109&ref=nb_sb_noss

There are now quite a few aftermarket brand new motors available, which seems like a better option than rebuilding mine. You can even get them with the pump assembly for a bit more. Any thoughts from the peanut gallery? I know the purests are going to hate this idea, and it will surely kill me because it isn't Toyota OEM, etc, but I'm really not interested in spending $1300 on a new booster assembly, but I also think it would be prudent to refresh the motor. Does anyone have experience with this route? Suggestions?

Given the extreme severity of the failure, cheaping out on the failure-prone part seems illogical.

$1300 is peanuts in the 100 game if you're keeping up with all the aging items. Depends if you consider your time and energy free I suppose.

As a spare part only to be installed in a trail/roadside failure? Sure.

As a pre-emptive replacement to protect against future failure? Absolutely not.

 

[nckwltn]

This brake system style is used across many toyota models, as well as some other makes. I used to have an '03 Mitsubishi Montero with the same brake system (might have been an identical ASIN part).

It seems like there is a common failure point in the motors. I took one apart and point out the failure point in this video: Similar to the post #13 that was noted by @SteveH

I found a motor in a pick-a-parts yard from the brake booster on a 4Runner. The motor bolted right in to my Montero booster assembly and worked for as long as I had the vehicle.

For ~100 bucks, it might not be a bad back-up solution while you send the original motor out to get re-wound and the commutator bars replaced.


However, brakes are fairly important... and you don't want to be up in the Rockies at high elevation with your family in the 100 and have the brake booster start to cause problems.... it can be a butt puckering experience coming down not knowing if the brakes are going to give way. Now that I know a little more about the system, I wasn't on the edge of failure, but it would have been nice to know that coming down out of the mountains! (this happened to me in my 100, the motor gave out on my wife in the Montero while driving around town. Thankfully she was able to get home safely)

 

[chriscosta416]

The brake system is common with 4wds with traction control from the early 2000s onward. The motor and accumulator are the 2 more common failures. @nckwltn the Gen3 was pretty much the same except for the line routings and ECU

 

[Bisho]

I'm really trying to decide on whether to rebuild the motor with 47960-60010 ABS PUMP BOOSTER MOTOR REPAIR KIT TOYOTA LAND CRUISER REPAIR KIT | eBay - https://www.ebay.com/itm/143907633979?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20200818143230%26meid%3D68b50db0f5a34056b6238486a99c2918%26pid%3D101224%26rk%3D3%26rkt%3D5%26sd%3D394417211995%26itm%3D143907633979%26pmt%3D0%26noa%3D1%26pg%3D2047675%26algv%3DDefaultOrganicWebV9BertRefreshRanker%26brand%3DToyota&_trksid=p2047675.c101224.m-1 or to buy the new Chinese motor. I am leaning towards the rebuild, but I was wondering if anyone had experience either way.

I wouldn't consider replacing the complicated parts with Chinese aftermarket. The master cylinder itself I'm rebuilding with the OEM kit.

 

[TexLexican]

Is the booster motor available on Impex? If the accumulator globes are the fraction of the cost then I’d assume the same for the booster.

 

[Bisho]

Is the booster motor available on Impex? If the accumulator globes are the fraction of the cost then I’d assume the same for the booster.

Toyota doesn't sell just the electric motor. 47050-60010 is the pump assembly, with the motor, and Impex has it for ~$1300, which is the same cost as the whole ABS assembly, now. Partsouq has it in the $800 range.

 

[yngmrostrvile]

I'm really trying to decide on whether to rebuild the motor with 47960-60010 ABS PUMP BOOSTER MOTOR REPAIR KIT TOYOTA LAND CRUISER REPAIR KIT | eBay - https://www.ebay.com/itm/143907633979?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20200818143230%26meid%3D68b50db0f5a34056b6238486a99c2918%26pid%3D101224%26rk%3D3%26rkt%3D5%26sd%3D394417211995%26itm%3D143907633979%26pmt%3D0%26noa%3D1%26pg%3D2047675%26algv%3DDefaultOrganicWebV9BertRefreshRanker%26brand%3DToyota&_trksid=p2047675.c101224.m-1 or to buy the new Chinese motor. I am leaning towards the rebuild, but I was wondering if anyone had experience either way.

I wouldn't consider replacing the complicated parts with Chinese aftermarket. The master cylinder itself I'm rebuilding with the OEM kit.

I saw this listing and was wondering the same thing. has anyone used this? the one I found looks like the same seller but $30 less on shipping.

Pardon Our Interruption...

 

[terrond]

I saw this listing and was wondering the same thing. has anyone used this? the one I found looks like the same seller but $30 less on shipping.

Pardon Our Interruption...

I bought one of these kits from partstrade on ebay for my son's 02 4runner. Worked great and will likely do the same for my LX470 with 225k - just need to be mindful that you should take apart the motor and measure the rotor length / take a picture for the for the ebay seller to ensure they send the correct rotor. I had to send back the first kit since it was too small. Its a very simple motor to rebuild and only a few parts involved.

 

[2001LC]

So can we just refresh booster motor? Yes. If that is all your budgets has room for..

But hands down best, replace the whole brake master assembly. If any clues suggest a failure may be near or a failure has occurred, do it for sure.

Replace or rebuilding brake booster motor, is a very good idea. Whereas brake booster motor is the part that failure, result in loss of brake booster pressure. Which effectively renders brake pedal useless or nearly so to vary degrees.

Once we bring pressure (back up to factory spec) with a increased RPM of new or rebuilt booster motor. Which just replacing a brake control wire can do. We'll often feel better brake pedal response.

But there is a downside to only replacing brake booster motor:

One of which, older system may not handle the increased pressure it will produce well!

Older brake seals in master and calipers. Especially in system not flushing timely or less than optimal brake fluid used. May not handle the increase pressure now produced with increasing RPM of booster motor. The brakes still work, provide we build pressure. i.e. booster system working and adequate fluid in the system to build pressure and transfer it to brake pads. But we'll often have other issues come up.

One of these issues we may see, as a result of increasing pressure. Is seals in master may leak. This condition produces a squealing sound (AKA dying seagull, AKA screaming banshee). A clue it is the master seals. Is, as we hear the squeal, we see bubble or ripple in brake fluid at front of reservoir. The sound is brake fluid leaking past seal(s) in master under high pressure.

We still have brakes in early stage of master seal(s) leak. But seal condition worsens with ever occurrence. At first, it's only while brake fluid cold. But as condition worsens, the seal(s) leak, even after they warm (expand). This result in booster motor running excessively long, try to keep pressure up.

The booster motor is designed to run short durations, of about 10 seconds. FSM warns us to not run longer than 2 minutes. Running longer or with lower AMP (resistance in wiring to motor, weak voltage, etc.). Result in motor running hot. This eats the commutator of brake booster motor prematurely. Now we're back to replacing the motor again. But this time the seal in master will be so damaged, motor will run excessively form the beginning and braking will be poor with soft pedal condition very likely.

We then end up in the shop again, with additional labor time and parts cost.

Since all 4 USA 100 series brake masters, became available (some were not) about 2 years ago and cost dropped. It really makes sense, to just bit the bullet and replace the whole brake master assembly w/booster)

Consider what we get: Booster motor, pump, accumulator, master seals, clean ABS screens & valves, new electronic all which have limited life span. Additionally, all other past in and on master assembly.

If on the fence. Look for the clue that point to health of brake system:

Brakes ...... Overdue write-up.

First and foremost: Brakes should only be worked by those, with high level of mechanical abilities and experienced with brake systems. With the age of all 100 series today, in our aging fleet. Any issue, with brake master assembly. IMHO, best and safest course of action. Have the whole brake...

forum.ih8mud.com

I've never replaced or even heard internal seals master being replaced. Nor does Toyota sell these. Additionally, thread end is stake in a way that, doen't lends itself to being removed.

Not in above picture, is the brake master plunge. Which is sold by Toyota.

This is a general bake master diagram from Toyota Technician handbook, not 100 series specific.

There is other issue that arise in master. Most are from incompatible fluid or poor fluid flush history. One such, is clogging in the ABS unit (black box on side of master). This opened ABS unit below; we see its filters clogged. After servicing booster motor and flushing. The ABS locked RL caliper. It was "believed" value stuck open, due to debris.

The electronic do sometimes fail. Which may have been cause of RL brakes lock up, mentioned above. We don't know for sure.

 

[Bisho]

I thought the motor simply turns a pump which pushes fluid into the accumulator, much like a well pump puts water into a pressure tank. This is the beauty of this system over old vacuum assist. You actually get pushes of the brake pedal after the motor fails to stop, instead of going straight to manual brakes. The pressure isn’t determined by the motor speed, but by the accumulator and pressure switch.

 

[NE Snowman]

I tend to fall on the cheaper/leave sleeping dogs lie, only fix what’s broken or aged out.

The brake system is on my PM list, even at $2000 it’s not worth my life, my wife’s, or god forbid hitting someone else. If the first went 200k, the second should longer if you keep fresh fluid in I would assume.

Pump seems easy and cheap but like 2001LC pointed out, there’s a lot more going on with the system and older parts possible aging out.

If you’re gear head and well in tune with your Hundy, I’m sure you’d be fine getting a pump and seeing how long it’ll go before you have seal problems.

 

[medtro]

I'm really trying to decide on whether to rebuild the motor with 47960-60010 ABS PUMP BOOSTER MOTOR REPAIR KIT TOYOTA LAND CRUISER REPAIR KIT | eBay - https://www.ebay.com/itm/143907633979?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20200818143230%26meid%3D68b50db0f5a34056b6238486a99c2918%26pid%3D101224%26rk%3D3%26rkt%3D5%26sd%3D394417211995%26itm%3D143907633979%26pmt%3D0%26noa%3D1%26pg%3D2047675%26algv%3DDefaultOrganicWebV9BertRefreshRanker%26brand%3DToyota&_trksid=p2047675.c101224.m-1 or to buy the new Chinese motor. I am leaning towards the rebuild, but I was wondering if anyone had experience either way.

I wouldn't consider replacing the complicated parts with Chinese aftermarket. The master cylinder itself I'm rebuilding with the OEM kit.

Brake Failure_uzj100 Power Brake booster repair-

This - 47070-60010 ABS PUMP BRAKE MASTER CYLINDER BOOSTER MOTOR 4RUNNER REPAIR KIT | eBay - https://www.ebay.com/itm/144028085078 - is legit. Arrived with DHL in 4 days from UK Florida. Total with shipping was $160. Came with brushes - didn't use them, see pics for reason. Seems to be...

forum.ih8mud.com

 

[Tummler]

I recall a couple very convincing posts from a couple years back arguing that that increased resistance from corroded connections to the electric motor are the primary cause for motor failures. I believe @2001LC subtly referenced this issue in his earlier post (@2001LC, were you the author of the posts I have in mind?). I loathe replacing old parts for no other reason than they are old because I subscribe to the notion that old parts are proven reliable parts. On the other hand, the brake booster is a known point of failure.

In light of the foregoing, I would closely inspect all electrical connections and possibly redo all connections with an abundance dielectric grease. If everything looked good while doing that, I would leave it be, with the understanding that your current parts likely will outlive whatever you choose to replace it with.

 

[TexLexican]

I recall a couple very convincing posts from a couple years back arguing that that increased resistance from corroded connections to the electric motor are the primary cause for motor failures. I believe @2001LC subtly referenced this issue in his earlier post (@2001LC, were you the author of the posts I have in mind?). I loathe replacing old parts for no other reason than they are old because I subscribe to the notion that old parts are proven reliable parts. On the other hand, the brake booster is a known point of failure.

In light of the foregoing, I would closely inspect all electrical connections and possibly redo all connections with an abundance dielectric grease. If everything looked good while doing that, I would leave it be, with the understanding that your current parts likely will outlive whatever you choose to replace it with.

Checking that connection is a legit concern. I have zero rust on my 100 except for the front recovery hook and that screw/connection.

 

[flykas]

Bumping this thread because I have a similar issue. Brakes work fine, but I got a dying seagull issue with pump motor not stopping and alarm glitching. Sometimes it all goes away when driving over some bumpy patch of road. And today I discovered that the connection to the motor is rusted out and maybe wet? Do you think it could be fixed with cleaning the connection ?

 

[SteveH]

I found that rusty connection so hard to access that'd be easier to pull the brake assembly, flip it over, and clean the connection. At that point, you should take apart the motor and check the brushes for wear. How many miles on the truck?