Weak Braking Power (1 Viewer)

[HankMoody]

Recent GX460 owner, 2012 model. Noticed the brakes are relatively weak, requires early braking, and foot completely to the floor to keep it from rolling. Rotors, pads, and tires are good. Plan to inspect fluid and potentially swap.

However, was curious if this was normal for a 2012 GX? I understand from other threads, owners have performed a rotor and pad upgrade, and is this because of the weak breaking power or simply “modding”

Appreciate the help. Thank you

 

[Rednexus]

Foot on the floor is not normal and would indicate an immediate safety concern. Assuming that you have fluid in the master (i.e, you don't have a leak in a brake line somewhere causing a fluid loss, as low fluid can cause the pedal-to-the-floor issue), you may have a a problem with the combined brake master cylinder/booster, which is known to fail at higher mileage.

Regardless, if the pedal is actually going to the floor, you shouldn't be driving the vehicle until it is fixed, as that can be a precursor to total brake loss.

 

[r2m]

Agree with Rednexus. If your pads and rotors look good and are within spec, I would suggest bleeding your brakes and adding fluid.
Note, I believe bleeding needs to be done by a certified mechanic or dealer because the ECU is involved, unless you have TechStream.
Acrad may know for sure if/when he see's this post.

 

[Acrad]

I used to a Motiv power bleeder/flush on mine. Simple one person flush job

 

[jdam]

I used to a Motiv power bleeder on mine. Simple one person flush job

Do you know which cap/adapter you used for the Motiv? I have a few other makes of caps but not one for Toyota/Lexus.

 

[Acrad]

Expensive cap but it works.. I paid around $46 for it back in 2019.

https://www.amazon.com/Power-Probe-BA10-Adapter-Toyota/dp/B004IQ96RK

 

[HankMoody]

Bled the brakes, braking has improved. Thanks yall

 

[r2m]

Did you need to add much fluid, or just bleeding and replacing spent fluid worked?

 

[HankMoody]

Did you need to add much fluid, or just bleeding and replacing spent fluid worked?

Just bled and replaced what was spent. Was visibly a significant amount of air in the lines.

 

[Rednexus]

Air in the lines is not normal. Usually the sources are a leak in one of the lines or a poor bleeding job by someone prior. It might be a good idea to inspect the lines for leaks

 

[HankMoody]

Air in the lines is not normal. Usually the sources are a leak in one of the lines or a poor bleeding job by someone prior. It might be a good idea to inspect the lines for leaks

No leaks. And fluid has stayed same level since purchase. Assumption was poor service done by prior owner/mechanic