Locked up parking brake!

[poleclimber63]

I own a 1998 SR5 4x4 V6 Auto. I had been towing my boat quite a bit and parked it (on a slight downward hill) with the parking brake set, for a week. It rained during this time. Finally the weather cleared, I then jumped in my beloved T4R to head to the lake, and I was shocked to find I was stuck--- as if my wheels were fixed in cement! I unhitched the boat, and gently rocked from D to R. Finally, I put it in low and gave it alittle power and BANG, it let go! The only thing I can figure, is the parking brake failed to release. I crawled under and checked the cable and it appears fine-- no rust and reasonable lubed. Also ok on the wheel hubs.... The only thing I haven't done is remove the rear wheels. Has anyone experienced this?

With the truck in gear, I felt the torsion movement of power being transmitted to the wheels.... I tried 4x4, same effect. I don't believe it had anything to do with the rear end or transfer case... I had the rear end fail on my Chevy a few years ago, and its pretty distinct! I now have been driving without a hiccup for the last 5 days, but it was enough of a pain to be alittle worried about having this happen in a remote location...

 

[TheDurk]

Your first suspect are the bell cranks. These are little levers on the outside of the rear of the brakes that the e-brake cables attach to. They have an arm that transmits the e-brake cable tension to the shoes inside the drum. They have a tendency to lock up and when they do they lock up HARD. You need to pull the drums to get at the mounting bolts for the bellcrank. Then you can remove them, pull the pivot pin, polish and lube it up, or just replace them. We in salt-loving NJ know this problem well.

Get under the truck and look at the BACK of the brake and see if the bell crank moves as a helper moves the e-brake lever. You have to push aside a rubber boot to really see what is going on.

 

[poleclimber63]

This is what makes this forum so great! Thanks for the feedback, I'll check the bell cranks at first opportunity. When someone acquires a vehicle, this forum can/has been a valuable tool for identifying issues! Thanks again fellow forum members-- I'll take your advice TheDurk, and I'll have a good look!

 

[cfranck1]

Here is a great writeup about seized bellcranks and how to make them work freely again..

Bell Crank Info

 

[badattitude]

Another possible cause may be leaking axle seals. Gear oil can get on the rear shoes and make them stick to the drums. Check and see if your rear diff oil appears low.

 

[poleclimber63]

Another possible cause may be leaking axle seals. Gear oil can get on the rear shoes and make them stick to the drums. Check and see if your rear diff oil appears low.

Wow! I just came home from a weeks' road trip and discovered last night that the drivers' side rear axle seal has let go! I was under the truck the day before we left on our trip and everything appeared good ie. no visible signs of leaks (I replaced rear diff oil a few weeks before). I believe its possible the seal may have started to seep which could explain the locked up rear brakes in July.... and then of course, with heating during our trip, it let go. I should have removed the drums... lesson learned... According to BigFishAllDay, its extremely important to ensure the diff breathers aren't plugged--- which could lead to seal failure...

 

[poleclimber63]

solution...

Update: As I had a rear axle seal failure, I took it to my mechanic for the repair... He worked for Toyota for 19yrs before semi-retiring... he owns a 4Runner himself and loves them! Anyways, he says this sticking brake problem is common, as the pads become contaminated and cause the sticking. In my case, the passenger side was just starting to leak as well! He says the seals usually only last between 120-150K miles... with regular wear. I've now been driving for a week since the repair (seals and pads), and I've not had anymore issues with the brakes.

 

[amalik]

Your first suspect are the bell cranks. These are little levers on the outside of the rear of the brakes that the e-brake cables attach to. They have an arm that transmits the e-brake cable tension to the shoes inside the drum. They have a tendency to lock up and when they do they lock up HARD. You need to pull the drums to get at the mounting bolts for the bellcrank. Then you can remove them, pull the pivot pin, polish and lube it up, or just replace them. We in salt-loving NJ know this problem well.

Get under the truck and look at the BACK of the brake and see if the bell crank moves as a helper moves the e-brake lever. You have to push aside a rubber boot to really see what is going on.

Hi Durk,

Im learning more about the bell cranks per my other new thread about rear break love where you referenced me to the pdf writeup.

Quick question, so in OP case here... Can the ebrake lever go up and down fully as normal, but the bellcrank pivot is still forcing the ebrake cable to push shoe against drum because of lack of grease in the pivot joint area?

That would be the only thing that makes sense to me, otherwise I assume OP would report that he can't push the ebrake lever down in the cabin.

Sent from my LGMS428 using Tapatalk

 

[TheDurk]

Hi Durk,

Im learning more about the bell cranks per my other new thread about rear break love where you referenced me to the pdf writeup.

Quick question, so in OP case here... Can the ebrake lever go up and down fully as normal, but the bellcrank pivot is still forcing the ebrake cable to push shoe against drum because of lack of grease in the pivot joint area?

That would be the only thing that makes sense to me, otherwise I assume OP would report that he can't push the ebrake lever down in the cabin.

Sent from my LGMS428 using Tapatalk

Absolutely. Its locks up set if left on at rest, then when lever is released it puts slack on the cable but the bellcrank still has tension on the shoes. The lever goes back to normal rest position just fine. Sometimes the bellcrank will break loose after a little bit of driving, then lock up again when left overnight. I had that until it locked up permanently and I had to do something.

I have a 5-speed so I always use the e-brake. It's been 5 years since I serviced them (I filled the boot with Anti-Seize) and they still work fine.

 

[3bears]

Update: As I had a rear axle seal failure, I took it to my mechanic for the repair... He worked for Toyota for 19yrs before semi-retiring... he owns a 4Runner himself and loves them! Anyways, he says this sticking brake problem is common, as the pads become contaminated and cause the sticking. In my case, the passenger side was just starting to leak as well! He says the seals usually only last between 120-150K miles... with regular wear. I've now been driving for a week since the repair (seals and pads), and I've not had anymore issues with the brakes.

that's the first time I have heard that the average life of the rear axle seals is 120-150k

 

[nobb]

Definitely sounds like symptoms of an axle seal leak causing the rear shoes to be oil soaked. Sometimes you can't tell the shoes are oil soaked just by looking. The proper answer is to replace the shoes entirely, but I just baked my shoes (because they still had alot of life left) with a hot plate to burn off the oil and they work great again.

 

[poleclimber63]

that's the first time I have heard that the average life of the rear axle seals is 120-150k

At the time, that's what he said. As an experienced Toyota mechanic--- and the fact he's done a TON of these, I trusted his opinion.

I've seen lots of trucks go longer and some less--- like mine. There are lots of reasons for the seals to fail: blocked breather, failed bearings and lack of diff fluid/maintenance to name a few. We all understand rear seals are eventually going to leak on our 4R's if you own them long enough, but compared to other vehicles, these seals aren't that bad. Just use OEM and don't worry for 150K...

 

[poleclimber63]

Definitely sounds like symptoms of an axle seal leak causing the rear shoes to be oil soaked. Sometimes you can't tell the shoes are oil soaked just by looking. The proper answer is to replace the shoes entirely, but I just baked my shoes (because they still had alot of life left) with a hot plate to burn off the oil and they work great again.

I had issues with the ebrake for a while until it became obvious with the centrifugal pattern on the inside of the rear tire

Here in the West, bell cranks aren't generally an issue as I discovered, but in the rust belt it happens.

Back in 2012, I had my mechanic change the seals and he replaced the shoes as well. Cool idea about baking the oil off the shoes, if you're on a budget. They're relatively cheap, so if they had been leaking and soaking the pads for an extended period of time, I'd just replace'm--- I'd be concerned they'd de-laminate from the plate or disintegrate.
Good luck!