Can somebody explain this to me? I am having a strange leak into the parking break. The break system is in good shape. No leaks anywhere. Parking break on the passenger's side is consistently covered in something oily. I have been monitoring break fluid for the past year. No problems there. Every time I check the rear breaks I see parking break assembly all covered in something.

If it was related to parking break cable, the driver's side would also be affected as well.

Here is the video of what I am talking about:

https://m.youtube.com/watch?v=tEPoRrDtEuo

There's no possible way the parking brake cable can leak fluid....because it's mechanical...not hydraulic, i. e. no fluid involved with it's function, that being said the "disk" brakes caliper or lines/hoses can leak fluid.....or the rear axle seal could be leaking gear oil from the differential, which would leak into the drum part of the brake disk where the parking brakes shoes/cable are, you need to determine what kind of fluid it is then you will know where the leak is, brake fluid and gear oil smell totally different, also if there's no fluid seemly on the brake caliper, that would seem to say it's the rear axle seal leaking.

Edit: @slonny I guess should have watched your video before replying, it's looks like it's the axle seal from what I saw in the video, the bearing may very well be bad as well which caused the seal to start leaking, check the bearing for play/axle up and down movement, there should be no play in the bearing at all.

This sounds like a better method of ruling out the problem than dismantling everything. Thanks! I will smell the break fluid today and compare the smell to the gear oil. Unfortunately I don't have any gear oil left, but I think this will do the trick.

It's hard to tell, but I didn't see any obvious leaks of brake fluid from the caliper. So most likely it is the axle seal leaking gear oil.

I will definitely check it out. It is probably a good idea to replace the bearings and the seal together. The car has 185k miles.

Looking at this video, it will be a lot of work. It also seems to be very expensive if done at a shop, so it will have to be a DIY project.

- YouTube

What type of press is good for the job? Do I need a 12T, or 6T will do? I was looking at these from Amazon for a very reasonable price. 6T may be a bit too short.

Amazon.com

Also make sure the axle vent is in fact venting, and is not plugged with mud, etc. A plugged vent can cause gear oil seepage past seals.

This is a good one. I changed it a year ago, but I will definitely check its condition. The old one was a complete mess. I know that this problem began a while back, so it might be the old one that caused it.

If that's the case, the leakage might have resolved after you replaced the vent. Get some Brake Clean, and spray down everything that has oil residue on it, then see if the seepage continues. Also check the gear oil level in the axle. Remove the fill plug, and see if the gear oil level is close to the level of the fill hole, when parked on level ground.

I agree clean it up, refill the diff with gear oil and see if you still have a leak before moving on to replacing anything.

When it comes to presses, the bigger the better, I know that anyone who has ever pressed a new front wheel bearing onto the hubs of these T4Rs has said you need a 20 ton press, so I'm not sure if the 12 ton is good enough for the rear or you need a 20 ton for that as well, either way you may want to check Harbor Freight for a press if you have one close to you...but you may also want to check around to see what a machine shop would charge you to do the pressing if you bring it to them....unless you think you would have other uses for having a press of your own.

On another note when you pull the axle be sure to check it where the seal contacts it for a wear groove, if it has a groove the new seal may not seal properly, I know of a couple of guys who replaced their seal and it still leaked because after many many miles the original seal had worn a groove in the axle, hard to imagine rubber wearing a groove into steel but it can happen after a long enough time.

Edit @slonny , I tried to watch the Youtube video you posted but the link appears to be bad, also you will need more than just the press to get the bearing pressed off and back on the axle, here's a link to a video that shows what else you need other than a press, also some other good info for doing this job.

Rear Axle Bearing Replacement on 4th or 5th gen 4runner Tacoma - How to Press Out Rear Wheel Bearing - YouTube

Completely forgot about HF Tools. That will be even better than Amazon. The guy in the video mentioned that it was very difficult for him to find a shop, and the dealer wanted an arm and a leg to get the job done. If the press will cost me $160, then I am already saving a ton of money. I will look around though.

I was thinking of just replacing the seal and the o-ring, and worry about the bearings when they show signs of failure. It seems like replacing the seal is pretty straight forward. I will definitely check for the groove as I do it.

This is the 3rd time this is happening, so I am positive that there is a leak. I will inspect the vent though and see if that may be the problem. If it is clogged up, then it is a different story.

After watching that video you will notice he was using a 20 ton press, which will cost more than $160, probably around $250, you also can't tell the bearing is bad until you get the axle out, the seal won't let you move the axle much while still in place to determine if the bearing is bad, once the axle is out is when you will notice any play in the bearing, so then you will need to get the press and other items/tools needed to do the bearing.

I believe it's the "spacer" that seems to ride in the seal and not the axle itself, if you noticed in the video that he had the "groove" on his old spacer from the seal.

Yes, it seems like it is the spacer that protects the shaft. His car has the same mileage as mine, so if I am pulling the whole thing out I may find similar wear and tear. Might as well just replace everything. If the old parts lasted 200k miles, I should be good for a long time.

I guess there really is no way to check if the wheel bearing has failed and cause a seal leak, unless I take everything off.

I also did some research on the press and the prices to press the bearing assemblies. Others are also saying that the prices are astronomical. You were right about 20T press. It seems like 12T press will be barely enough to do the job. 20T is a must.

Rear Axle Bearing And Retainer: 12 ton Press - YotaTech Forums

Check around and you may get lucky and find a good used 20 ton press for less money like he did, where are you located?

HF Tools sells one for $250. That is the cheapest one I found. I am in Los Angeles. Craigslist has a few adds, but they are all for 12 and 6 ton presses.

Break - what you do at work, often involves coffee.

Brake - the thing that stops your vehicle.

You’re welcome.