ABS break pad replacment

I have a 2004 Honda Pilot that needs new back breaks. Can someone tell me the procedure for doing this without screwing up the ABS?


I strongly recommend that your first purchase be a manual. The trick to doing an ABS system is that you bleed the fluid out of the bleeders when you push the pistons back in the calipers rather than backpressuring the system and pushing the fluid back into the master cylinder the way you could with old style brakes.

But please, please get and follow a manual. It’s a $20 investment in your safety.

Thanks for the info. Yes, a shop manual has been ordered but it wasn’t $20. More like $70 and the only place that I could find it was on Helminc.com. Still…worth every penny. Thanks again!!!

I was thinking of a Haynes manual. But the one you ordered is much better and well worth the added $50.

Agreed. The more expensive shop manual will pay for itself after the first couple of repairs. Well done.

The Helm manuals are a bit pricy but you’ll find that over time it’s a great investment. The Chiltons paperback manuals primary use is bird cage liner material as they’re full of incomplete and incorrect informatiion.

You will need a special tool to screw the pistons in the rear brake calipers back into their bores. This tool can be fabricated, purchased (they’re not too expensive), or one can be rented from parts houses such as AutoZone, O’Reillys, etc.
When the tool is returned your rental money will be refunded.

When the park brake operates a brake caliper the piston is on a threaded shaft. The piston is designed to self-adjust during use by unscrewing itself off of the threaded shaft. This is the reason why the piston must be screwed back in while being compressed. Hope that helps.

In addition to knowing whether the caliper piston pushes in or screws in, you need to open the bleed screw while pushing the caliper in. This is to prevent the old fluid from contaminating the sensors. If you coordinate it properly so that you don’t draw air in, no need to bleed them. Otherwise ABS is the same as non-ABS.

Personally, I prefer not to open a bleed valve without a pee cup (with fluid) and a tube. Your coordination may be better than mine…

I’d like to know what sensors you think you are going to contaminate in the system?

Wheel speed sensors are not exposed to brake fluid and I don’t know of any other sensors in the system.

You should ALWAYS open the bleeder when retracting a caliper piston. You should NEVER force the old fluid back into the master cylinder. This is especially true with ABS brakes.

I remove all the old fluid from the master with a turkey baster and refill it with fresh fluid. Then pump up the brakes to position the new pads and check the fluid again. Using this procedure, master cylinders and calipers last a long time…ABS units too…

the abs sensors are not inside the calipers or pistons. why would the piston retraction method effect the abs?

and what piston screws in? i have never heard of this.

and i have only had the pleasure of using a helms shop manual a couple of times, but you probably made the BEST investment there. they are the BEST manuals i have seen. the mechanics use them.

Why do my Haynes manuals not specify opening the brake bleeder for changing brake pads for either my 85 Olds Cutlass or my 2001 Dodge Grand Caravan (with ABS)? All it says to do is remove some of the fluid from the master cylinder to prevent it from overflowing and to use a C-clamp on the piston to force it back…

On some cars the rear pistons screw in. ok4450 explaine it further up. They do on my 2000 Maxima. I use a tool that I think is supposed to be used to tighten the collar on the bearings on the pedal crank of bicycles.

Thread check

When you do that, you are forcing old, possibly dirty and contaminated fluid back up the lines and into the master cylinder/ABS unit. Why not discard that well used fluid and make up the loss with fresh fluid, thus protecting the expensive brake system components from contamination.

If you prefer the Haynes Manual method, go for it. Most ASE mechanics use the procedure I described…

No, I was just curious why they wouldn’t specify the same procedure…thanks for the explanation.

Having been the one that pointed out the difference being that with ABS systems you must open the bleeders when you push the piston in, I feel compelled to respond to Caddyman. Pushing the fuid back in non ABS systems will not hurt the system, but I agree that a better practice is to purge the old, in essence cycling some new fluid in. My main point was to illustrate that backpressuring an ABS system can cause damage, as opposed to a non-ABS system.

How can you possibly damage the system? Isn’t the brake system designed to handle the pressure of braking? How can pushing back a piston create enough pressure to damage the system?

That the biggest bunch of baloney. I’ve actually worked on ABS systems for years and have never damaged a ABS system by pushing back a piston and not opening a bleeder.

Plus let me make this perfectly clear… removing the fluid from the master cylinder, installing new fluid and opening the bleeder to let the fluid out is a good idea. But to suggest that you can damage the system by pushing the piston back without opening the bleeder shows just how little you know about the system.

You can stand by your comments all you want but you are wrong.

“the abs sensors are not inside the calipers or pistons. why would the piston retraction method effect the abs?”