Request for advice where to start our 71 project (1 Viewer)

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That housing has already been ground down to accept the larger Birfields.

That is really interesting bc it has 6 spline Birfields. Are there aftermarket 6 spline BF that have larger heads and required grinding? The inside did look very well preserved and like someone had put newer stuff in it? See pics above.
 
I have the Chevy disc brakes front and back on my stock axles. They are great, I've had them on for years and have never caused any problems... they just eliminated the infernal drum brake problems!
Never eliminate the vacuum activated 4wd system! it is so reliable and who needs a hole cut in the tunnel and another lever sticking up in the way? I've never had to service the vacuum system on my '71 I've owned it for 40 years.

BTW I use the cheap stinky spray engine cleaner (not foam type,) spray on every stuck rusty crud bolt and let it soak in for a day or so then spray again and gently wrench the bolt a little back and forth until it comes out. I seldom have broken off one. I learned to quit being impatient and not to spray and then a few minutes later shear off the bolt. I've never found anything that works better.
 
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I have the Chevy disc brakes front and back on my stock axles. They are great, I've had them on for years and have never caused any problems... they just eliminated the infernal drum brake problems!
Never eliminate the vacuum activated 4wd system! it is so reliable and who needs a hole cut in the tunnel and another lever sticking up in the way? I've never had to service the vacuum system on my '71 I've owned it for 40 years.

BTW I use the cheap stinky spray engine cleaner (not foam type,) spray on every stuck rusty crud bolt and let it soak in for a day or so then spray again and gently wrench the bolt a little back and forth until it comes out. I seldom have broken off one. I learned to quit being impatient and not to spray and then a few minutes later shear off the bolt. I've never found anything that works better.
How do I know if it works? There is a part on the firewall that looks very crusty and most of the dash knobs at the moment wont pull out. And there is this thing that is coming out of the crusty box and I don't know what it is.



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That's the cable that goes to the 4wd button that activates the vacuum switch. On mine that cable goes through that hole just above your lower heater hose on the firewall, it looks like someone put 1 or 2? cables or wire through it. And above that hole, almost obscured by the upper heater hose in your photo is where the manual choke cable goes through. When they put in the 2F it looks like some of the cables may have been rerouted. That vacuum box is probably alright but yes that cable is probably frozen solid.
 
May or may not have been ground, you’ll be able to tell when you go to insert (so try first before assembling and packing. I’ve got some long bodied warn hubs in the garage if you need them … depending on birfs you find ;)
 
That's the cable that goes to the 4wd button that activates the vacuum switch. On mine that cable goes through that hole just above your lower heater hose on the firewall, it looks like someone put 1 or 2? cables or wire through it. And above that hole, almost obscured by the upper heater hose in your photo is where the manual choke cable goes through. When they put in the 2F it looks like some of the cables may have been rerouted. That vacuum box is probably alright but yes that cable is probably frozen solid.
Are these cables available? I think the hole you are saying this vacuum 4wd cable should go through is the hole that the choke cable is poking thru. I’ll take a look, but what else is required besides the cable to make the vacuum system work? I see under the truck there is a thingy that has some hoses coming out of it. The hoses are just about toast. Not sure if that is part of the 4wd vacuum system or not.
 
May or may not have been ground, you’ll be able to tell when you go to insert (so try first before assembling and packing. I’ve got some long bodied warn hubs in the garage if you need them … depending on birfs you find ;)

How do I know what length Birfs to buy? Do I just use the same length as what I have? Which is about 9” long. When I looked at Birf suppliers they all seemed to be 9.6” long.
 
I don't know if cable is still available check Spector off road and many other sources here. I know my vacuum hoses under there are original, look ratty but still work perfect. easy to replace those hoses if need be. I think SOR has parts for the actuator or whatever it's called that is connected to your transfer case . Also Classic Cruisers here in Poncha Springs Colorado ( (719) 539-7722) would probably have the cable you need for the vacuum shift. Yes, humidity and rust is an evil demon. I lived in So Florida for a few years and always kept my '71 in the garage with a thrift store dehumidifier cycling. One other thing, my stock original front and rear axles, birfields etc have crawled all over the Colorado mountain range rugged mine and "jeep" trails and have never let me down.
 
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This is from @woody
The 76-78 Birfields have a longer shaft length, ~1/4" IIRC. They have a slightly smaller diameter bell design.

Shaft length and critical bell diameter (across the flats) is the same on a 79+ birfield as a Newfield.

When running minitruck/stock Aisin hubs with 79+ birfs, you install a outer clip in the birfield groove. When running 76-78 "stock" Warn/Aisin hubs, you install a fender washer/bolt into the end of the birfield to use the minitruck/79+ birfs.

76-78 birfs are "not compatible" with minitruck or later Aisin hubs, since the spline section of the birf extends too far into the lockout.
More hub info here:

Long story short, you can buy the ‘76-‘78 birfields (stock/nitro/longfield) or the ‘79+ 40/60/mini birfield (stock/nitro/longfield) … this is up to you, but you have to buy the corresponding hubs to make it work.

HTH -
 
This is from @woody

More hub info here:

Long story short, you can buy the ‘76-‘78 birfields (stock/nitro/longfield) or the ‘79+ 40/60/mini birfield (stock/nitro/longfield) … this is up to you, but you have to buy the corresponding hubs to make it work.

HTH -

This does help clear things up. So basically 79+ short Birfields need the short Aisin locking hub. And consequently, 76-78 longer Birfields will require the taller Aisin locking hub. Now to find the parts.
 
Also - you’re going to need to know if you have small or large pattern knuckles to get the correct steering parts, good thread with pics/measurements up in FAQ.
When you say "steering parts" what are you referring to? I know what you mean by small or large pattern as I have read that so I can check mine for size.
 
When you say "steering parts" what are you referring to? I know what you mean by small or large pattern as I have read that so I can check mine for size.

Still not sure what you mean by steering parts. A buddy has the centering tool that I can borrow but please clarify your comments about steering parts. Thx
 
I think he's talking about what knuckles and steering arms you have. Small pattern/FJ40 arms use smaller taper tre's, and of course large pattern are larger. You may have to get a proper length tie rods and ends, if they didn't come with the parts.
 
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I think he's talking about what knuckles and steering arms you have. Small pattern/FJ40 arms use smaller taper tre's, and of course large pattern are larger. You may have to get a proper length tie rods and ends, if they didn't come with the parts.

Ok thanks for that. My current TRE bars are both slightly bent so may need new bars anyhow.
 
Thought you might like this...

That looks like a pretty good setup for the ease of it. Of course, nothing I do is easy LOL. But since I have most of the parts needed I am going with original Toyota stuff. Still looking for some used Birfields to save having to spend more money on new stuff. So anyone with some Birfs from 79-84 let me know. Also, Aisin hub of same years.
 
That's the cable that goes to the 4wd button that activates the vacuum switch. On mine that cable goes through that hole just above your lower heater hose on the firewall, it looks like someone put 1 or 2? cables or wire through it. And above that hole, almost obscured by the upper heater hose in your photo is where the manual choke cable goes through. When they put in the 2F it looks like some of the cables may have been rerouted. That vacuum box is probably alright but yes that cable is probably frozen solid.

I need to figure out how to fix this. I spoke w George E and after hearing what is involved with converting to H42 4Spd I have decided to stick with what we have and get it operational. Any help would be appreciated.
 
Are these cables available? I think the hole you are saying this vacuum 4wd cable should go through is the hole that the choke cable is poking thru. I’ll take a look, but what else is required besides the cable to make the vacuum system work? I see under the truck there is a thingy that has some hoses coming out of it. The hoses are just about toast. Not sure if that is part of the 4wd vacuum system or not.
Those hoses going to the transfer case are on the same switch circuit as your seized cable. My hoses are original on my 71 and aren't pretty but work great. Would be nice to get that seized cable out of the way and see if you can manually test that switch, you might be surprised.
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The vacuum switch sends vacuum to the actuator on the transfer case. That knob on the dash (that you appear to be missing) only switches between 2wd and 4wd. The lever next to the heater is a direct linkage to switch between H-N-L.
 
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