Seized Piston in Front Brake Caliper

[docfeelgood]

What is the best way to handle a ceased piston on the a front brake caliper?
I'm trying to fit new pads into the caliper, but the inner brake piston will absolutely just not budge. The other 3, no problem.

Any ideas?

2004 4Runner SR5, w/ apprx. 74,000 miles

 

[kylebacc]

Lot's of threads on this. IIRC it's pretty much a "replace the caliper" kind of fix. I'm not sure if there are ways you could attempt to free it.

 

[K.C.]

Frozen Calipers - How many others had this problem?
http://www.toyota-4runner.org/4th-gen-t4rs/57869-frozen-calipers-how-many-others-had-problem.html

 

[teampwr2]

So I have a question ? theory on the frozen Pistons in Brake calipers.....Those who have had frozen pistons are your 4 runrs 2 wheel drive ?? If they are 4 wheel drive do you ever use 4 wheel drive? More specifficlly ever have ATRAC engage ??/ I Just replaced my STOCK brakes at 53,000 miles Calipers were fine pistons were free and easy....I Have v6 4wd and I 4 wheel Every week and ATRAC and DAC are always hammering away ... my thought is the ATRAC and DAC both Are pounding the brakes and the pistons dont ever go very long without .." the Hammers "" going on /off any thoughts ??? Or Am I Just out in left field ?

 

[sr5hi]

What is the best way to handle a ceased piston on the a front brake caliper?
I'm trying to fit new pads into the caliper, but the inner brake piston will absolutely just not budge. The other 3, no problem.

Any ideas?

2004 4Runner SR5, w/ apprx. 74,000 miles

If the piston is stuck, you are either going to have to replace or rebuild the caliper. If you free the stuck piston, it is likely to become stuck again. The caliper pistons usually get stuck because of corrosion or contaminants that form on the piston/caliper bore, or the inner seal becomes distorted.
To try and free the piston, remove the brake pads and unbolt the caliper from its mount. Support the caliper and DON'T let it hang by the brake line. Place one old brake pad or small block of wood against the piston and use a small C-Clamp to apply pressure to push the piston back in its bore. I have not done this procedure on 4Runner calipers, but have used this method on other vehicles with success.

 

[UnhappyWithCostco]

Toyota 4Runner Caliper Piston Failure Notify NHTSA

Hello Fellow Toyota 4Runner owners. I also had my front caliper pistons seize up on my 2003 Toyota 4runner SR5. I literally blew a stop light with this failure. Apparently Toyota corporate is not getting the message. This very serious brake failure cost me $742.00 to repair with no guarantee it will not happen again.

The solution is for all affected Toyota 4Runner owners to get serious and notify the National Highway Safety Administration and file an official complaint.

https://www-odi.nhtsa.dot.gov/VehicleComplaint/thankyou

Otherwise you are just blowing smoke. We need everybody that has experienced this type of serious brake failure to get on board and file your complaints with NHTSA.

Thank you.

 

[Bossman]

[MENTION=211203]UnhappyWithCostco[/MENTION] see my post re: safety concern over seized brakes in this thread:

http://www.toyota-4runner.org/problems-warranty-issues/61456-add-me-frozen-caliper-club.html

Wow - I made that post over 7 years ago!

 

[wc11]

How did you blow a stop sign with 1 seized caliper?
It would just pull to one side if anything.
I think filing a complaint on a 15 year old used vehicle is pointless.
Just buy different brand calipers and call it a day.

 

[matt922]

Hello Fellow Toyota 4Runner owners. I also had my front caliper pistons seize up on my 2003 Toyota 4runner SR5. I literally blew a stop light with this failure. Apparently Toyota corporate is not getting the message. This very serious brake failure cost me $742.00 to repair with no guarantee it will not happen again.

The solution is for all affected Toyota 4Runner owners to get serious and notify the National Highway Safety Administration and file an official complaint.

https://www-odi.nhtsa.dot.gov/VehicleComplaint/thankyou

Otherwise you are just blowing smoke. We need everybody that has experienced this type of serious brake failure to get on board and file your complaints with NHTSA.

Thank you.

LOL @ username. Nothing is your fault, its always someone out to get you. :rofl:

 

[Bumbo]

It happened to me too... I was getting uneven pad wear and the truck was pulling to one side when breaking.

I fixed it with a Centric reman calipers from RockAuto. Caliper, rotors, pads, and lines. Everything came out great, performance is restored.

 

[matt922]

Any of you guys having problems with stock calipers have a religious history of bleeding the brakes every 2-3 years? It becomes saturated with condensation/moisture which I could see causing corrosion problems very easily.

 

[Nunya Biznass]

Apologies for the necropost, but I joined the club this week as well.

The front driver side chewed up the outboard brake pad and quickly ground it to the metal. The inboard pad (with the wear indicator, natch) still has at least 3/16ths on it. Got it off and found the lower piston on the outboard side was stuck.

My ride is an '06 V8 SE, with ~125k, and to my knowledge, the brake fluid has never been flushed before today. Kinda surprised it went this long without problems.