Stuck E-Brake and brake fade

[calithirteen]

What's up 4runner world!

So here's the deal. Braking on my truck has been anything but stellar. Completed the tundra upgrade but didn't feel much of an improvement. Then replaced the rotors and pads with a set from the dealer last year. Slight improvement but not much. So I noticed one time when having to stop short, there was no screeching but instead a horrible grinding noise (ABS issue?) and the stopping power was not good. As far as i know the brakes were bled correctly but I'm wondering if there is something else going on such as the master cylinder or brake booster.

Add to this my ebrake has been sticking. Pulled apart the bell cranks, grinded and repainted. Seemed to help but now the ebrake on the passenger side is still sticking occasionally. As far as I can tell it doesnt look like the rear main seals are leaking.

What am I missing here?

:wtf:

 

[Bearded Cabbage]

Oddly enough, I have had this same problem before.

It usually happens on cold start-ups or when first pulling out of the driveway.

Not so much a 'Grinding" but more of a "shuttering" from possibly stuck rear shoes.

Im going to start by doing a fluid flush...

Awaiting reply from someone else with more possible suggestions.

 

[mtbtim]

I have heard the wheel cylinders on our rigs can stick or leak so maybe you're rear wheel cylinders need replacing.

 

[calithirteen]

Oddly enough, I have had this same problem before.

It usually happens on cold start-ups or when first pulling out of the driveway.

Not so much a 'Grinding" but more of a "shuttering" from possibly stuck rear shoes.

Im going to start by doing a fluid flush...

Awaiting reply from someone else with more possible suggestions.

That sounds very similar to what I have going on. Cold starts and I have to give it a little gas to get the truck to move. Also if i use the ebrake then release it, it seems to stick.

 

[BWJones]

Check out the e-brake bell crank. Pretty common for those to freeze up and give you these symptoms.

 

[calithirteen]

Check out the e-brake bell crank. Pretty common for those to freeze up and give you these symptoms.

I guess you missed that part. They definitely were not helping and I went ahead pulled them apart, sanded,repainted and greased already. Still having issues.

 

[mtbtim]

Since people who've done the Tundra upgrade report significant improvement with their brake power, maybe there is an issue with your master cylinder or brake booster like you mentioned already.

 

[JohnMc]

My passenger/right side ebrake was occasionally sticking on. Turned out to not be the bell cranks, or the cable. It was the little lever on the driver's side of the axle that sort of 'distribuutes' the cable tension from the cable leading to the handle to both rear brakes. It was sticking, and would keep the passenger side brake pulled shut.

Took it off, cleaned it, anti-seized it, reassembled, no more problems.

'Grinding' is probably the BAS pump running. When ABS activates, it bleeds hydraulic pressure off of the wheels it senses are locking up. If it does enough of that, it could feel like the brake pedal is sinking. Which people would NOT like, for sure. So a pump activates which replenishes the pressure in the system, to keep the brake pedal fairly level. It's rather harsh sounding.

 

[calithirteen]

stopped being lazy and pulled the abs sensor and found gear oil in there so clearly i have bad axle seals. Went and spent $400+ on replacement parts but my mechanic won't touch this nor will his machine shop as he stated this axle is a nightmare to work on. Calling the dealership to see how much this is going to brake the bank.