L5wolvesf

You dun did a purdy job there pilgrim. If I were you I'd drink a toast.

RAD4Runner

Thank you, Sir! Thankful that the truck has not been abused.
A Drink to that, Aye!

L5wolvesf

Aye Matey! Great place to stash yer rum. I need to get to diving at some point.

RAD4Runner

LOL! BTW, I'll be driving to Wahweap on Monday, for volunteer clean-up work on Lake Powell. You or other Yota Bros happen to be along this way?

L5wolvesf

I'm in a town named Cottonwood - south of Flagstaff. You're going round the other way. There are a couple Yoda guys here and at least one in Flag, I'm sure they're more around Northern AZ.

flg8r22

iTrader: (1)

Glad to see you hit up Napa Ray. USA USA 🇺🇸

RAD4Runner

Was on the way to NAPA to return brake shoe cores when I felt the brakes go spongy. Sure enough, left rear cylinder was leaking. Fortunately, NAPA has replacement in stock so I replaced it right there. Was so tired and hungry so I took late lunch:

...Then how to bleed the lines without an assistant? Seen enough bad guy movies? - LOL!
A few sprints between pedals and under the truck and all was good

... and borrowed tubing from rear window washer...


The Stock Aisin cylinder still looks good. Maybe I just over-extended it while wrestling with the brake shoes. Anyway, I'll see if rebuild kit is inexpensive enough and I'll do it. Bought a second cylinder, just in case the passenger side acts up.

RAD4Runner

I would like to rebuild the original Aisin rear brake cylinders. This kit looks like the one, correct?

papawhellie

I know your a purist but rockauto probably has those rebuild kits for less than 3 bucks. I actually bought some but havn't found the time to hone one and build it. I buy a lot of stuff from RA and
always google the part numbers around trying to determine country of origin and cross shopping for price. Sometimes an ebay seller or Amazon might have that part with country of orgin in the description. I have AC delco PF52 filters for my Honda shadow made in the UK.
I looked 1.29 cents and advics cylinder which is Aisins new moniker is 15.50. Shipping is the crutch with them. I always get a cart full for about 20 bucks shipping. Wiper blades are very cheap and under universal parts you can buy the blades refill by length and refill your stock arms!

wyoming9

iTrader: (1)

Having done a few cylinders over the years a smooth bore is critical I always a small hone to clean things up.

Things need to be super clean a tiny piece of grit will cause a failure in a short time

It was worth it to buy new ones from Toyota for my 92 4Runner

Terrys87

iTrader: (1)

I seen it was mentioned earlier but from 84-88, the rear brakes and cylinders have different lengths. If you have the smaller cylinder the tab on the brake show will be longer and vice versa.

What you may be thinking is a leaky cylinder could be the piston has popped out of the cylinder. You said it was spongy. When I got the wrong cylinder on my 86, I lost all brakes due to no fluid. Your brakes will work for a few times until the cylinder pops out. The wheel cylinders will bolt up to the axle hub and look correct but it is the length of the cylinder that you need to pay attention to.

RAD4Runner

Thanks guys.
The cylinder that leaked was the stock one that did NOT have a problem. I think the piston merely popped out too far and the rubber cup got misaligned. I'll try cleaning it and inspecting the rubber cup. Had to buy the NAPA replacement because I did not have time before driving to Lake Powell for volunteer work .

cbh148

It's a good thing you didn't go with the brake shoes from Oreillys. I did, and my driver side shoes were dragging -- even when adjusted to the full-retract position, the brand new drum wouldn't clear over those new Oreilly shoes without having to smash it on with a rubber mallet, so I wasn't surprised when the short test drive's burnt smell indicated that the driver side was dragging. I believe this warped the new drum, so even though I ponied up and paid nearly $80 for some new OEM Toyota shoes (which went on fine with the drum easily clearing them), my brakes felt very warped during use and warranted me buying another new drum to replace that warped drum with only 6 miles on it. I took some good pictures comparing the shapes of the Oreilly (Brakes Best Select) $16 shoes to the OEM ones, if anybody would be interested.

Finding new OEM shoes wasn't difficult, though the guy at my local dealership was confused for a brief moment when he thought the part number wouldn't work for my '94 DLX 4x4, then he quickly saw that whatever the old part number was, it got superseded by the one I inquired about. It's the same shoes used for several different models across many years; 1986-2000 4Runner, 1987-1995 Pickup, every year of T100, 1995-2003 Tacoma, and even 2000-2003 Tundra. My local dealership wanted $112 for a set, and they stocked them since they're used on so many models. I bought mine on ebay for $79.75 with free shipping by searching for the part # 04495-35230, but had I seen this thread before buying OEM, I would've gone to Napa.

RAD4Runner

Hmmm... Didn't know O'Reillys' were that bad.
I wonder if OEM for later years would fit the 1986 to 1989. It would be nice if someone has tried and shared his experience.
Very happy with the NAPA $16 pads and cylinder so far. Drove to Utah/Arizona border to help clean up Lake Powell and saw no issues at all (That's why I was off-the-grid for a week). Emergency brakes holds so well now; before it took more that 17 clicks to hold...

RAD4Runner

AAARGH! Right-Side cylinder now leaking!
Got hope with no problem, but need to work on this tomorrow as early as possible.

Short-term Plan:
To get the truck safely- going, I'll just buy the cylinder from NAPA again because the first one I got seems to be working well; Yes, brakes felT good and e-brake holds very well even before the spec'd 17 clicks.

Then Long-Term:
I'm debating whether to rebuild the old ones or not. After taking the first one apart, aside from the dirt inside that I was able to clean out* I found badly rusted spots. Not sure if worth cleaning and rebuilding since I found some supposedly OEM Aisins online (Although other stores, including Toyota Parts Deal, list them as discontinued).
One for $14 here.
Another for $34 here.
I wonder how legit the above are.

Your thoughts on those rust spots please?
Your thoughts on above online offerings for OEM Aisins?







*Yes-definitely need to drain and replace brake fluid

millball

Difficult to tell about those cylinders. Use a brake hone on them and see how they clean up.

You can do it before you buy the rubber kits.

RAD4Runner

Awesome. Thanks for the tip. Will check if O Reilly's has a loaner. Don't wanna spend the $15 for another tool when NAPA sells a whole cylinder for $16.

RAD4Runner

Stock cups and pistons in good condition. No tear, no rotting nor cracks, but cylinder has rust spots. So my theory is... Because of thicker new shoes, cups are pushed closer to center or cylinder and are now hitting rust spots which break the seal against the cylinder wall. If I can polish cylinder walls, Ill rebuild- I do not like throwing away rebuildable OEM parts.
If that fails, I'll buy brake cylinder from local NAPA.

ewong

I find THIS tool

https://www.summitracing.com/parts/l...RoCCdQQAvD_BwE

invaluable on working on THIS spring...(the one marked A)

The tool allows yo create a right angle "handle" via the screw down clamp, on the STRAIGHT section of the spring, allowing you to PULL the hook end over and drop the hook into the notch/hole in the brake shoe.

https://lh3.googleusercontent.com/2m...=w1350-h760-no

RAD4Runner

Rear Brake Cylinder Could Leak After Installing New, Thicker Brake Shoes


Thanks, Ewong! Yes, I wish I had that tool earlier. My only challenge was with the long return spring so it would have helped greatly. To replace leaking cylinders, I simply expanded the adjusters so the shoes will clear the cylinder and I did not have to remove the shoes anymore.

ALAS! While the drum innards look pristine, as Wally says, the cylinders have probably 31 years' worth of rust and junk. Below is the right-side cylinder I removed today.



The first cylinder I removed looks and feels badly-pitted. Today's cylinder does not seem as bad. However, Since rebuild tool (hone) plus seal kit would cost more that NAPA's new cylinder ($16 plus tax), and I'm pressed for time, I just got another NAPA cylinder.

As mentioned earlier, cups, rubber boot and pistons look good, and I had no trouble with the brakes before. So my theory is:
1) With the thin shoes, cups operated farther outward.
2) The area where the cups did not operate/scrape got rusted/pitted.
3) With thicker shoes, this time the cups operated closer to the center of cylinder, over the rusted/pitted spots and that broke the seal against the cylinder wall.