Latest and greatest on preventing tcase leak out of parking drum? (1 Viewer)

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I sort of disengaged from Cruiser world for about 7-8 years, but kept my 40. Now rebuilding a transfer case, and the last time I built a transfer case (in 2004) the thing to do was machine the speedo gear housing for a second seal. Have folks decided if that is still worthwhile or does a leak free 3sp transfer case really just hinge on a groove-free parking brake drum and a properly preloaded output shaft?
 
I've only done it on my 4-sp., but IMHO, if your drum isn't grooved where the single seal rides and it doesn't leak, run that until it does. Once that setup starts leaking, go for the double seal setup. The double will eventually groove out where the two seals ride, so might as well put that off as long as possible if the single is still holding.
 
I took mine all apart and found the groove and then installed the speedy sleeve, it went on without much trouble and then proceeded to leak all over my freshly cleaned brake drum. I just ordered the double seal from Georg over at Valley Hybrids / Cruiser Brothers. They are super responsive and supposedly that’s the fix. Fingers crossed. I have had and been around several FJ 40s but not one with a working parking brake!
 
I would have to say yes, and yes. I just took my speedo housing up the road to a machine shop 5 min, and 10 bucks later I was pressing two new seals in. I have been replacing speedy sleaves for 20 years. It's time to try this other route. If I had a drum that was looking like new I wouldn't need 2. The front output flange gets that way to. I just got one of marlin,s double front output seal too. I just pulled out a perfectly good 3 speed t-case yesterday. It was just trying to put an end to leeks
 
We have the dual-seal rear extension housing kits in stock and ready to ship.
Kits include:
Machined/blasted/painted housing.
2 seals already installed
New gasket
New stake nut
New Speedo o-rings
New drain/fill plug crush washers
Pretty much everything needed to complete the job. We thought it would make everybody’s life easier if we supply the complete kit. Obviously, we also stock everything else to fix your transfer case, transmission and whatever else you might need for your Landcruiser.
Happy to help!

Georg @ Valley Hybrids @ Cruiser Brothers
Shop 209-475-8808
Sales@valleyhybrids.com
 
I started this thread 2 years ago, then decided to dump my SM420 and buy a complete H42 and split tcase from @orangefj45 .... so that option exists too ;)
I may be known as an “enabler”.

😂😂😂

Georg @ Valley Hybrids @ Cruiser Brothers
 
Georg, what is the difference in the 2 set ups ? the H42 & split have better manners, closer gear spread ?
 
I'm told the split case is stronger and quieter than 3spd/4spd solid cases. For me- I'm tired of driving an SM420 which is effectively a 3spd on the road and I found I rarely used 1st-low when wheeling because that kind of traction doesn't exist east coast. So an H42 with 3:1 in the case gives me a stronger, quieter combination with a true 4 spd and the same functional 1st-low range (I did most wheeling in 2nd-low with the SM420).
 
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After various attempts and leaks, I found that drowning the splines in FIP prevented the 2nd leak you may see - which is gear oil coming through the splines and out around the nut in the middle of the drum. I tried using FIP on the nut and washer faces, and it didn't work. Coating the splines in FIP did the trick.
 
After various attempts and leaks, I found that drowning the splines in FIP prevented the 2nd leak you may see - which is gear oil coming through the splines and out around the nut in the middle of the drum. I tried using FIP on the nut and washer faces, and it didn't work. Coating the splines in FIP did the trick.
Can you elaborate a little on that, specifically which area of the splines to put the FIP? Is it best on just the area around the splines where the washer and nut go? I need to do this fix as well for my 40 to stop an annoying leak.
 
Before I go on - your FJ40 transfer case brake drum can leak from 2 places:
  1. Around the drum shaft seal and into the drum body. This is the traditional leak that contaminates the brake shoes.
  2. Through the output shaft splines and out around the nut. This does not contaminate the brake shoes, but coats the outside of the drum with gear oil, and flings it onto the truck or the ground.
The solution I am describing (following) only fixes case #2 above.

I tried the minimalist approach of meticulously cleaning the face of the parking brake drum and then caulking the washer and nut. This failed immediately. This is easier and less messy, but did not work for me.

So, I removed the parking brake drum, cleaned the output shaft splines and drum splines with Q-tips coated in brake cleaner until all was surgically clean. I then coated the output shaft splines (where the drum splines ride) with Toyota FIP. I also coated (lightly) the corresponding splines in the brake drum itself. I then slid it all together (with caulk oozing out) and installed the nut, washer, and driveshaft. It has not leaked since.
 

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