A Ratcheting Brake Caliper Piston Spreader Can Make Brake Jobs Quicker And Easier

This cheap tool makes spreading brake caliper pistons a cinch.

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Image for article titled A Ratcheting Brake Caliper Piston Spreader Can Make Brake Jobs Quicker And Easier
Image: Jalopnik / YouTube

Over the past few weeks we’ve looked at an ozone generator that supposedly helps to get bad smells out of a car, a flare nut wrench that helps to make easy work of changing out brake and power steering lines and the rivet nut or nutsert, a little fastener that creates a nice, threaded hole where once there was only misery. This week’s cool tool is a ratcheting brake caliper piston spreader, a tool that’s better at the job at spreading brake caliper pistons than a C-clamp.

This suggestion comes from reader and former mechanic, Le Monstre, who says that this is better than the old C-clamp and a brake pad trick. They also suggested flexible hose clamp pliers, which were the subject of a previous cool tool.

Replacing a set of worn out pads and rotors is a really gratifying experience. It’s a job that just about anyone can do and provides such a night and day difference in braking that you can’t help but be proud of yourself once you’re finished. A brake job is also a great job to teach beginner wrenchers with, too.


As your brake pad and rotor surfaces wear down, the brake caliper pistons need to move further to push the pads against the rotors and stop your car. When it’s time to change out worn brake parts, you’ll usually find that the caliper’s pistons are pushed out pretty far. Pushing those pistons back in is a necessary part of any brake job, but how do you do it?

If you’re working on something tiny like a Smart Fortwo, or a motorcycle you could actually push the pistons back in with your hands. But what about something bigger, like a pickup truck? A common trick is to pull out a C-clamp and one of the used brake pads, then set up the clamp to compress the brake pad against the pistons. This is a pretty neat hack and works for many vehicles. But what if you’re dealing with calipers that make using a C-clamp hard, such as 4-piston calipers where the pistons are on both sides?


This is where a ratcheting brake caliper piston spreader can save the day.

Image for article titled A Ratcheting Brake Caliper Piston Spreader Can Make Brake Jobs Quicker And Easier
Screenshot: starastronomer / YouTube

A ratcheting brake caliper piston spreader consists of a ratchet and two plates. When you engage the ratchet the plates expand out, spreading the caliper pistons. No more swearing because your c-clamp bent or because you just can’t get it to fit.

Watch the starastronomer YouTube channel demonstrate how these work:

Ratcheting brake caliper piston spreaders run pretty cheap, too. They’re about $25 for a generic model with one from a name brand like Lang coming in at about $45.


Do you know of a weird or unique but must-have tool that every wrencher should have? Do you want to see us put a type of tool to the test and see how it performs? Shoot me an email or drop it down in the comments!