77 disc brakes for a 72

[Ralph140]

I have a 72 L/c that I use for hunting and fishing and minor off road trips. I need to do a brake job on the rig and and think I would like to put on Disc brakes. After a lot of reading on I H8 mud have found a lot of commentaries on the use of kits, the use of mini truck discs, but not as much on using stock cruiser parts. If it will work out and I can still get it, I have access to a 77 L/c axle with disc brakes in tack. Are there any pit falls? And what problems may I encounter in making such a conversion? I would swap out the entire axle etc. but the 77 rig appears pretty well abused and I am not sure of how good the front end is. The other lingering question is the use of the existing M/C and using a proportioning valve. Any comments on that topic will also be appreciated. I may have missed it so I will ask if you all know of a particular thread or threads that cover my situation.
If the assembly is no longer available, is there a "best" kit? I do not plan to run the rig hard and I am not into heavy off roading any more. And as simple as some of these kits seem to be ( Downy; Man a free etc.) for an old man, I may just opt out for a kit. I appreciate all of the feed back you folks give to those of us with lesser Toyo brains. Thank you.

 

[Josie'sLandCruiser]

Hi All:

Use the "search" function - you will find lots of info on disc brake conversions.

That being said, I swapped an entire '78 disc brake front axle under my '74 FJ40, using the existing '74 (drum brake) master cylinder and brake booster, which worked fine with the '78 disc brake parts, though I did remove the resisdul valve that is in the front brake circuit (of the master cylinder.)

If you intend on re-building the entire front axle assembly (a good idea) while doing the front disc brake swap it is actually easier to leave your existing drum brake front axle tube bolted in place and simply installing the knuckles-out from the disc brake frontend.

Good luck with the project - it is well worth the effort!

Regards,

Alan

 

[watrob]

If it was me I would get the 77 model FJ and pull out the front axle and do full rebuild, then put in my 72 model. That's what I did, I got hold of a 84 model front axle.

You are going to have to do a full rebuild on your current 72 front axle whether you buy mini truck knuckles with disk brakes or a kit . You will still need all those parts plus more. It is far easier to rebuild the 77 axle and it also keeps your current FJ on the road until your ready to slide in the whole new axle.

If you feel quite confident in yout ability to remodel your 72 axles and do the knuckle change and the other extras by all means do it. But I found that having the whole new axle on a stand was a far easier rebuiild and it gave me time to clean the axle housing up & paint , do the diff, bearings, seals, berfs, gaskets, preloads etc and not have any pressure to get finished in one weekend.

 

[65swb45]

As long as one of the axles gets torn down and you end up replacing the 30+ year old knuckle bearings, you're good either way.

If you keep your existing housing, you will have to grind your knuckles to accept the larger birfs, but you won't have to mess with the brake lines as much.

If you swap housings, you won't have to grind on the housing, but you'll have to fuss with the different brake line drop as well as swapping pinion flanges. No biggie either way if you're a mechanic or better.

If your brake m/c is more than a few years old, you should just consider buying a brand new disc brake one. They're a LOT cheaper than they used to be, and it's very good insurance.

Best

Mark A.