Tackling a 2008 ABS actuator replacement. What tools do I need?

You shouldn't need much of anything at all special 10 and 12 mm sockets a quarter inch drive ratchet a few extensions for the quarter inch drive setup a flex socket or a flex joint and honestly other than a screwdrivers in the pry bar that should be about it I just did this on my '09 I don't know a couple months ago didn't take very long at all I spent more time cleaning and farting around than doing the work and then for bleeding other than the 8 mm wrench to crack the zerk fittings it's 8 or 10 that's it and if you get the bleeding instructions somewhere here you can bleed the brakes without tech I did mine without it and I have tech I just didn't feel like charging the laptop and getting it out then I found some instructions that seemed to work and it's been working ever since everything's perfect like it was new so that was that and I didn't need tech to bleed and everything was great

 

Regardless of what Tom claims, use the Techstream bleed procedure. You might be able to flush brake fluid from the reservoir to each of the corners without Techstream the old-school way but you cannot get brake fluid through the actuator/accumulator assembly thoroughly without using Techstream.

Additionally, you might need to do a couple calibration procedures like a linear offset, for example, which is just easier with Techstream.

Just ensure you have a solid 12 V supply (i. e. start with a fully charged battery and leave the charger attached) before you start so it doesn't die when you get close to the end of the procedure.

 

I couldn't get it to work quickly enough and the procedure that somebody posted right here that I cannot find miraculously now One of you regulars posted it for me it was 14 pages long from what looks to be the manual and numbered accordingly like the Toyota paper manual would be numbered One of you guys posted it that's the procedure I used relays out relays back in blah blah blah been working fine ever since I didn't mess with the yaw rate sensor or any of that I had previously replaced the clock spring and had text dream connected and being used during that time but it didn't say that I needed to do anything with the clock spring or the yaw rate sensor or any of this stuff in the car and wasn't giving any codes and my brake pedal was just like it was when I bought the car similar to brand new so I left it alone and started driving my car for my business like I do everyday and it hasn't asked me to bleed hook up anything or throw any codes other than the PO420 that I've had for 2.7 years now and looks like it will never be going away and that's okay I'm getting 45 to 47 at every fill up and that was right at factory so I have no complaints If text dream would have connected bled the brakes and done the stuff I would be sitting here talking about that but that's not what happened. So yeah regardless of what I say try to get the tech stream to do the do. If it does not you can bleed one set of brakes with the relay out and the other set you have the relay in you crack the zerk let it stream until there's no air pissing close dessert and go to the other side That's only for the set that is not coupled to the pedal it's only electric. And that's that Good luck should be uneventful to be honest about it especially if you're paying $800 to $1,000 for a brand new part I'm using a used part many people won't do that

 

Check that the techstream setup works before doing the repairs. Some here have reported problems with some cables when trying to do bidirectional commands like the ABS bleed. Others had no difficulty.

Check early on that all your bleeder screws open. You likely want a good "flare" wrench that fits the brake line nuts. IDK the size (12mm?, maybe 10)

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Second the flare wrench suggestion. All my brake work has been on old rusty stuff, but stripping those brake fittings is not a good idea. You might consider cleaning the visible threads and spraying with a PB Blaster or something similar. When unscrewing make sure the brake line is not spinning with the nut, sometimes they get stuck together and you could end up twisting the line and breaking it. If we learn from our mistakes I have a PHD in brake systems!

 

There are crow's-foot flare wrenches. The repair manual suggests a 10mm one. It can get into little spaces and you can turn it with a ratchet and extension. You can even torque it to a known value on installation (provided you do the math to account for the added length of the crow's foot).

 

I'm getting prepared to tackle this job x3 very soon. One item on my list is a USB extension cable to allow having my laptop outside the car while performing the bleed procedure (hopefully right next to me).

 

I have no idea, but it is not the way I'd do it.

If your battery is old and likely weak as you say, I'd verify that is the case and then replace it before starting this job. If it turns out to be old but not weak, it will still need to be fully charged before you start. If you don't have a modestly priced fully automatic multi-stage 12 V battery charge, then I'd get one of those too. You will be surprised how often it will get used once you have it.

 

As long as you keep the center of the crow's foot at 90° to the torque wrench, there is no correction needed.

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I do find lots of web sites that say the same thing, but I'm not sure I'm convinced yet. It might be easier to convince me that no correction is needed with the crow's foot at some angle θ to the torque wrench but where θ might not be exactly 90°. Pythagoras and I were scratching our heads over that.

I did find one page that says instead "use the crow's foot at a right angle (90 degrees) to the shaft of the torque wrench. With this configuration, the difference in torque is truly insignificant and can be safely ignored." I think I could buy that more easily.

Some of the other sites say stuff like "Yes, the distance increases by a small amount if you do the trig. However, if the force is applied 90° to the handle, the Y-component of that distance goes away and you're back to the exact length of the wrench." It sounds very clean, but too clean, and I have doubts.

If that were an actual theorem, you should be able to picture it just for grins with a nine-foot-long crow's foot and believe it still makes no difference, and I can't say I'm there yet. If it only makes sense for a typical small crow's foot, that puts it back in the realm of "difference is insignificant and can be safely ignored" approximation, which I'm thinking is more where it fits.

I'm surprised I haven't found even one page that does a complete picture with torque vectors and goes through it. I'd be even more surprised if there really isn't one. I'm sure I just haven't found it.

 

Ok, I'm a convert. Three of us talked it over for nearly 20 minutes over lunch yesterday without a conclusion, but some time after lunch Pythagoras finally got through to me.

To make the numbers easy, he told me to imagine a 3 foot long crow's foot at 90° on a 4 foot long torque wrench and give it a 5 pound pull (perpendicular to the torque wrench, of course).

In normal use of the torque wrench, that would be 5 perpendicular pounds on a 4 foot moment arm, or 20 foot pounds.

With the 4 foot torque wrench and 3 foot extension at 90°, the moment arm from my hand to the fastener is 5 feet, and the torque would be 25 foot pounds if my 5 pound pull were perpendicular to that, but it's not. When you project my 5 pound pull onto a line perpendicular to the moment arm, it's 4 pounds, so the resulting torque is 20 foot pounds again.

And for any right triangle you make with a crow's foot or extension of any length, the right triangle for projecting the pull on the handle will be similar in the same way, so the "no correction needed at 90°" holds up, and is not just a close approximation.

So we have some easy cases, where if L is the torque wrench length and E is the extension length, and Ti is the torque indicated on the wrench and Ta is the actual torque delivered to the fastener,

• if the extension's at 90° to the wrench, Ta = Ti
• if the extension is straight along the wrench away from the handle (making it longer), Ta = Ti(L+E)/L
• if the extension is straight along the wrench toward the handle (making it shorter), Ta = Ti(L−E)/L

If we pick θ = 0° to be straight along the wrench away from the handle, so θ = 180° is straight toward the handle, then those easy cases can all be written Ta = Ti(L+E cos θ)/L

And it looks like for any other angle θ, you can use the Pythagorean argument above to show the same formula still applies. (Which is nice to know, as sometimes the obstacles and space you're working in just won't let you put the crow's foot at exactly 0° or 90° or 180°.)

Which ends up being very close to what that other web page was saying in "the Y-component of that distance goes away". It had just left out too many of the steps to make it clear why the torque worked out that way.

 

Yeah, I did the math many years ago, figured out that 90° was "very close" to 0 correction, and forgot the details ever since.

You want an afternoon with Pythagoras? Use law of cosines to figure out piston position (distance down the bore) based on crankshaft angle. There might be a neat little formula out there, but deriving it was...interesting, and ugly.

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No kidding. And that's why the movement of the piston up and down is not quite a sine wave with respect to crank angle—it's got skinnier tops and fatter bottoms—which is why its Fourier expansion includes some vibrations at bizarre frequencies.

 

It is probably more than you need, but if you are happy with the price then go for it. Here is another Schumacher that has a smaller footprint, is a bit cheaper, and would do equally as good a job.

Schumacher SC1321 Fully Automatic Battery Charger, Maintainer, and Auto Desulfator - 3A/6A, 6V/12V - for Cars, Motorcycles, Lawn Tractors, and Power Sports

There are many Noco options and any that fit the bill would be a good option too.

Displaying voltage isn't really important, mine doesn't and I don't miss not having it either. I just go by the status lights. When I have wanted to know the voltage, just because I was interested to know, I just put my DVM over the battery terminals.

Harbor Freight also has some budget models that would work for a cheaper price.

It really comes down to how you envisage you will utilize the charger as to which features you deem important to you.

As an aside, any models that have a quick connect/disconnect attachment would be well worth having. If it doesn't come with the charger but is available as an accessory, it would be worth purchasing separately. Anything that makes life easier and quicker will ensure you use your charger more often.

I have only used it once out of interest more than anything else. The reality is if you're looking after your battery with regular charging from when it was new, you will never need to use the de-sulfating cycle.