Master Cylinder

Does anyone know what the dealership would charge to replace a master cylinder on a 2007 2wd ABS PreRunner?

 

no, but you can do it yourself, not too hard, definetly get a OEM Toyota part, how you know you got a bad master cylinder?

 

My truck wouldn't shift out of park one night as I was leaving work and wouldn't start. I couldn't get it out of park to roll it back for a jump so I waited and tried a few more times and on the third try the truck started and everything appeared fine. On the way out of the parking lot my brakes felt touchy like real sensitive but I thought maybe I was tired or just over thinking things. I make it about 1/2 down the highway and brakes lock up. I felt my truck want to stop and I thought it was the tranny but as I pulled over and took a look I could smell that burnt or hot brake smell.

 

That doesn't mean the master cylinder is defective.

It could be several different things:

Stuck caliper piston.
Parking brake dragging, stuck.
Defective wheel bearing.

Just to name a few. Don't just throw money at it. And the Master Cylinder would be at the very bottom of my suspect list. The master cylinder 99.999% of the time causes weak braking not stuck or dragging brakes.

 

I replaced my bad front wheel bearing. Checked both sets of brakes up front nothing stuck or hung up. I also bled the brake fluid and it seemed to be really dirty like dirtier then any fluid I ever bled in the past I assume the previous owner never changed or bled the OEM fluid since he was the first owner. Is there a recommended life span of the fluid or how often I should completely empty the system and replace with new fluid?

 

With normal use every couple of years... With the fluid as bad as you described I would suspect a caliper piston is sticking.

 

It always gives me knots in my stomach when something happens like this and knowing it could be a handful of things. Wish me luck hope all is well and thats all it was.

 

It felt like it was just the front driver side the side with the bad bearing because the smell was coming from there and that rim which was recently washed was the only one with dust on it.

 

Maintenance says to replace the fluid every 4 years or 40k. So 2007->2011->2015, the truck had missed two replacement intervals already.

How did you check for a stuck caliper? Were the pads worn evenly?

 

sounds like a caliper piston seized up, the whole story sounds a little funny

 

Thanks!

 

It was odd I check my fluids regularly all were at the correct levels and I drive my truck to work and back daily. I knew the front wheel bearing was bad because the guy I bought it from informed me it would need replacing. I never had this happen on any vehicle I owned.

 

If you can't shift out of Park, that's an unrelated problem. Most likely a bad brake pedal switch. If the brake lights also aren't coming on, then definitely a bad brake pedal switch.

 

Brake lights are working how do I check the brake pedal switch?

 

^If your brake lights are working, the brake pedal switch is OK. Can you shift out of Park now?

 

Yes shifts fine now thanks. This forum has helped me a lot I appreciate it.

 

Anytime I had a Master Cylinder fail the brake pedal would just go to the floor.

 

It was real weird and yes everyone told me master cylinder causes a soft pedal and booster is a firm pedal. My truck was fine on the way to work then leaving it just felt weird the peddle was a bit touchy but usable and then on the highway the front right caliper just locked up. I thought it was the wheel bearing because that bearing on that wheel was bad when I bought it and I put off installing the new one which I did the following day. I took the truck for a ride it seemed ok on side streets then the next day it locked up again in the highway. I'm not that skilled in mechanics and was frustrated to took it to a local shop I have used before. They claimed it was the master cylinder and very dirty brake fluid. They replaced the master and fluid and its been working fine since so I don't know. I think it was just the front right caliper and maybe the vibration from the bad bearing loosened up some seals cause I inspected the caliper with my buddy who swapped out the bearing and it looked ok no visable leaks or damage. I'm at a loss for why the repair worked when everyone afterwords told me a bad booster usually causes a stiff pedal.