For Sale Help with older 12 Spline locking hubs

I have a 77 FJ40 I am rebuilding with Axles from a 71. I am missing one of the front locking hubs. I have searched the internet and have not been able to successfully find hubs for my axles. They are 12 spline. Any suggestions?

 

[shawnfj40]

If you are already having trouble finding parts, its only going to get worse. The 77 axles were far supperior.

 

[Dedtruk]

I have a 77 FJ40 I am rebuilding with Axles from a 71. I am missing one of the front locking hubs. I have searched the internet and have not been able to successfully find hubs for my axles. They are 12 spline. Any suggestions?

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Don't use the '71 axles. Use the '77 axles with disc brakes, better hubs (higher spline count), etc. Or if you're stuck with the '71s, convert to discs using parts from an FJ60 or FJ62 (40 parts too, but more money). Or use minitruck (solid axle parts - use the FAQ to search for how-to) parts to convert your '71 axles, but mini parts are getting scarce and expensive too. All of these conversion suggestions get you better hubs than the '71s. You could even use after market parts to convert to discs, but that doesn't solve your hub problem ... and some kits use ... ahem, crappy GM parts, or very nice but expensive Wilwood parts.

If you must use the '71s, they use six spline hubs - count the splines on the axleshaft, not on the hub gear. The hubs you need aren't hard to find. Look in the classifieds here on Mud and on CL (I see whole drum brake axle sets from time to time, cheap). Look in the clubhouse for Bay To Blueridge ... bound to be someone down in VA who has those hubs.

Oh, and not to rain on your parade, but the drum brakes use a different brake master cylinder than your '77 truck should have in it assuming you still have the original type of master. Why go backwards from drum (which are more expensive to fix than the disc brakes and don't perform as well) to discs? Can 'o worms, brother. Find a disc axle!

Unless you absolutely must, don't bother with the '71 axles. By the time you spend the money to fix those drum brakes, you could have sourced a disc brake front end and been miles ahead. Just my $0.02 ...

Ask a moderator to move this thread to the FJ40 tech section too. This section is for whole rigs for sale, which may be why you're not getting much response. GL with your project!

 

[Ted Kush]

Don't use the '71 axles. Use the '77 axles with disc brakes, better hubs (higher spline count), etc. Or if you're stuck with the '71s, convert to discs using parts from an FJ60 or FJ62 (40 parts too, but more money). Or use minitruck (solid axle parts - use the FAQ to search for how-to) parts to convert your '71 axles, but mini parts are getting scarce and expensive too. All of these conversion suggestions get you better hubs than the '71s. You could even use after market parts to convert to discs, but that doesn't solve your hub problem ... and some kits use ... ahem, crappy GM parts, or very nice but expensive Wilwood parts.

If you must use the '71s, they use six spline hubs - count the splines on the axleshaft, not on the hub gear. The hubs you need aren't hard to find. Look in the classifieds here on Mud and on CL (I see whole drum brake axle sets from time to time, cheap). Look in the clubhouse for Bay To Blueridge ... bound to be someone down in VA who has those hubs.

Oh, and not to rain on your parade, but the drum brakes use a different brake master cylinder than your '77 truck should have in it assuming you still have the original type of master. Why go backwards from drum (which are more expensive to fix than the disc brakes and don't perform as well) to discs? Can 'o worms, brother. Find a disc axle!

Unless you absolutely must, don't bother with the '71 axles. By the time you spend the money to fix those drum brakes, you could have sourced a disc brake front end and been miles ahead. Just my $0.02 ...

Ask a moderator to move this thread to the FJ40 tech section too. This section is for whole rigs for sale, which may be why you're not getting much response. GL with your project!

Thank you Dedtruk. I have already completed the disk brake conversion on all four wheels. This whole rebuild has and is a learning process for me. I do have a 1979 rear axle (drums) that I could put on this, but not the front. The 71 axles came off a "spare cruiser" I purchased for parts. The PO had 1 ton chevy axles on it, however, the conversion was never completed, and I had no way to mount up a 205 TC to the rear axle. I'm trying to return the drive train back to stock from the TC back. Engine is 350 and tranny is TH350 with an AA conversion . i purchased a set of 6 spine Warn hubs from a fellow IH8MUDr. The IH8mud blogs have been helpful. on a side note, Regarding the master cylinder, I purchased an aftermarket duralast dual reservoir from Autozone. It seems to be working fine. Is there something I should know about this not being an option? I do not know how to move to the tech section.

 

[Dedtruk]

Thank you Dedtruk. I have already completed the disk brake conversion on all four wheels. This whole rebuild has and is a learning process for me. I do have a 1979 rear axle (drums) that I could put on this, but not the front. The 71 axles came off a "spare cruiser" I purchased for parts. The PO had 1 ton chevy axles on it, however, the conversion was never completed, and I had no way to mount up a 205 TC to the rear axle. I'm trying to return the drive train back to stock from the TC back. Engine is 350 and tranny is TH350 with an AA conversion . i purchased a set of 6 spine Warn hubs from a fellow IH8MUDr. The IH8mud blogs have been helpful. on a side note, Regarding the master cylinder, I purchased an aftermarket duralast dual reservoir from Autozone. It seems to be working fine. Is there something I should know about this not being an option? I do not know how to move to the tech section.

You're most welcome, I hope my input is helpful.

I won't pretend to be an expert in brakes (!) but I can suggest that you look into an adjustable proportioning valve to dial in your rear braking pressure. You may or may not need it, but based on what I've read, I think the odds are you do. I have read how to test in an open area to be sure your front brakes lock up before the rears do (IIRC), otherwise your truck may swap ends under heavy braking ... That isn't fun, speaking from experience. Short wheelbase trucks are prone to it, especially with a high center of gravity (lifted suspension) and big tires. Ask me how I know this ... Anyway, I'm sure you can ask around the forum and look online to find the info you need on four wheel disc conversions.

As for moving the thread to the tech section, I think you gotta ask one of the moderators to do that. Anyway, have fun with your project and post some pics!