Rising Sun Member Forums

Rising Sun Member Forums (http://www.risingsun4x4club.org/forum2/index.php)
-   General Tech Forum (http://www.risingsun4x4club.org/forum2/forumdisplay.php?f=17)
-   -   FJ40 Drum Brake Wheel Cylinders (http://www.risingsun4x4club.org/forum2/showthread.php?t=7225)

RicardoJM 05-28-2008 08:52 AM

FJ40 Drum Brake Wheel Cylinders
In researching replacement cylinders for my drum brakes, I have learned that CCOT has different part numbers through the years. Marks Offroad has cylinders that fit my build date (142-01B) and their rarity commands a premium.

The build date on my fj40 (December 1970) puts me in a grey area from the CCOT information - it does not look like they have the cylinders I would need. Add to this the fact that I know my rear axle is from an FJ55 (it has the triangle mounts for a stabalizer bar) and I don't know if my front axle is original and I am unsure how to best determine what is the right replacement cylinders for my truck.

I'm (actually the BoomBoom) is going to get back in there today/this evening to double check the brake hose is not the source of the leak. Presuming the leak is not coming from the hose, I have a few questions for your collective consideration...

What should I look for the determine the correct part number for replacement cylinder?

It seems the axel production date is important - do you know where I would find this date?

Do any of you know from first hand experience what the differences are in the cylinders?

Would it be possible to go right to the CCOT parts for years 9/71 - 7/80?

lfd270ben 05-29-2008 12:38 AM

I rebuilt my wheel cylinders and napa had all the parts or new ones youmight want to check with your local parts place they could probably get the right parts for cheaper then ccot. I have a 72 though.

Rzeppa 05-29-2008 01:37 AM

CCOT's are not exact replacements for our 71s. I would trust Mark Algazy to get you the right parts.

RicardoJM 05-31-2008 11:00 PM

Update on progress and things learned
Consistent with my other experiences with the FJ40, there is always something new to learn. After researching the brake cylinder rebuild process a bit more I decided to give it a go. I thought my worst case would be that I over hone the bore rendering the cylinder unusable and have to buy a new one. At $5 per cylinder rebuild kit, it seemed like a reasonable enough first step. A quick call to Napa and the next day I picked up a couple of rebuild kits so I could do both cylinders on the affected wheel. My plan was to do the other front wheel next weekend. So, this morning I cleaned up a bit of the gunga off the backing plate.


While cleaning out the old grime it was clear that the soft brake hose had seen its better days and was over due for replacement.


With the leaking cylinder out, it was time to lay out the parts and take a picture for help out in the reassembly later on. It was about this time that I noticed that the cylinder from my truck had more replaceable rubber parts than where in my rebuild kit. :confused:


Some researching on the net and reading of the brakes section of the Body and Chassis manual and I learn that this cylinder is not for the front brakes, but for the rear. Front brakes have a single piston and a cylinder bore of 1 1/4" and the rear brakes have dual pistons and a cylinder bore of 7/8". My FJ40 is running rear brake cylinders up front. :eek:

A quick check of the cylinders on the rear brakes confirms that their bore size is appropriate for an axle from an FJ55, they are stamped with 15/16.

Not knowing if my "wrong size cylinder" problem was limited to just the one leaking cylinder I removed all four from the front and sure enough the are all sized to be on the rear brakes.


Despite the comfort I got from knowing the cylinders were all the same size and knowing that consistency is generally a good thing - I'm not sure it is a good idea to run the rear cylinders up front even though it appears it can be done.

Another quick call to Napa and they have all four front cylinders at their warehouse. They are on the way to my local store and I'll pick up on Monday if I get out of the office early enough. With a bit of luck, I'll find the time to get them installed, bleed the system and drive the 40 to the meeting on Wednesday. :D

Rzeppa 06-01-2008 01:02 AM

My understanding is that 1-1/8 (going by memory, pretty sure 1-1/8, not 1-1/4) front and 7/8 rear is indeed stock on our 71s. In addition, CCOT has told me that they sell the 1-1/8s as an upgrade over the 7/8 for the rear. I have used them (indeed they are installed right now) and can say they have worked just fine for several years now. I will also say that when I ordered in replacements from NAPA (after dealer informed me that they are officially unobtanium), they DID NOT FIT. I had to take them back, which is when I got the CCOT units. NAPA's parts book said they would fit, but when I tried to install them I found the hydraulic fittings all wrong. 1971 is a funky year for Land Cruiser drum bakes, things became much more standardized on later 1970s wheel cylinders. As I wrote before, I would trust Mark for the exact right parts for exact stock for your month/year build. But, as I wrote above, the CCOT parts are working for me right now.

The primary downside to the CCOT parts is that you can not put a flare wrench on the bleeder fitting because of it's recess, although a regular open end wrench works fine. I have not had an issue with the larger bore causing excessive rear braking, although there is slightly more pedal movement required due to having to move more fluid; it is not a major issue and is easy to get used to.

For everyone snickering and about to make the "switch to disks" comments, once you have your Land Cruiser drum brakes properly maintained, they work just fine and will put your nose on the windshield. As for wet braking, I have been pleasantly surprised by how well the brakes worked right after fording the South Platte on Hackett Gulch. And shoes last at LEAST twice as long as pads in my experience. I have to adjust my cylinders on my drum brake Land Cruisers less often than I have had to replace pads on my disk brake ones. In my experience, the main advantage that disks have is not having to adjust them. One of these days I might try the later model runner calipers with the dual pistons and see if they are that much of an improvement over the single piston units.

RicardoJM 06-02-2008 10:56 PM


Originally Posted by Rzeppa (Post 75740)
I will also say that when I ordered in replacements from NAPA (after dealer informed me that they are officially unobtanium), they DID NOT FIT. I had to take them back, which is when I got the CCOT units. NAPA's parts book said they would fit, but when I tried to install them I found the hydraulic fittings all wrong.

Jeff, you hit the nail on the head. I dropped by to pick up the new cylinders and the hydraulic fitting was too small. The counter guy did some research on the 1970 model year and it also will be too small. I called Stevenson and they can get the cylinders for my build from KS - but they are about the same price as it would be to get them from Marks Off Road. At $300 to replace the front four cylinders it is getting to be a significant enough dollars that I may look for the front knuckles from a late 40/60/55 and make the switch to discs up front.

Having just gone through the front axle service, I think I'm up for the rebuild including the trunnion bearings this time. :D

Rzeppa 06-02-2008 11:20 PM

Hi Ricardo, $300 is insane money for four cylinders. As I wrote, I tried to get cylinders from Stevinson. The add-on to that is they took my order, but I didn't find out until a week or so later that they found out they are no longer available. For new cylinders, I'd go with either Mark's Off Road or CCOT. I trust both of them.

It's up to you - swapping front disks is a nice upgrade in not having to adjust, but for the money I'd just go with Mark's or CCOT aftermarket cylinders..

MDH33 06-03-2008 09:02 AM

Hey Ricardo, I know your pain. I have gone through and replaced all my wheel cylinders and lines on my 40. Gets expensive but brakes are kind of important. ;)

I opted to stick with my drums rather than do the disk swap. The cost of cylinders pales when you start looking into replacing calipers, disks, etc.

If you decide to go that route, there's a guy selling a 60 front axle:


I could use the third for my 60, so if you were interested in getting it, I would throw in. Let me know.

All times are GMT -6. The time now is 12:16 PM.

Powered by vBulletin® Version 3.7.1
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.