79 axle pretty much the same as 71?

lx450landcruiser

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ok thnking about getting a 79 front axle with disk brakes and swapping it under my 71 which doesnt. other then the brakes is it a simple bolt in? everything will line up correct?

thanks
mike
 
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No

79 axle will have 3.73 ring and pinion gears in the diff.
If you swap the diffs you will be OK.
you can also simply swap everything from the steering knuckles out (including the birfields) and have the same effect. I think this would be easier and cheaper than buying new u-bolts, swapping thirds (to swap the thirds you unbolt all of the diosc brake stuff anyhow).

Just swap the knuckles and be done with it. You will also want to put in new trunion bearings.
 

lx450landcruiser

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ok ok this axle stuff is new to me so if you would take pitty on me could you explain all of this so me? Im trying to do this as fast and cheap as possibe as im going to sell the truck but i would like disks on the front. i was under the impression i could simply swap the fronts out and it would work?

thanks
mike
 

lx450landcruiser

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Mr. Toad said:
... or let whoever buys it figure it all out.
funny but no way . im trying to do this cheap yes but im not cutting any corners.

i guess ill just have to do it the hard way.

mike
 
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Jukelemon said:
Find a 76-78 front axle and you will be fine i.e. all have the 4.11 R&P

IIRC these years have a smaller birf and to use a mini birf or newer than 78 you have to open up the axle housing for the newer birfs? I could be wrong on this.

Myrle
 

lx450landcruiser

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ok so how about if i take my stock 71 3rd member out i think its called a 3rd member? basically the pumkin out and put in in the 79 axle would that work? or is this way more work then i think? Like i said this is new stuff to me so any help is appreciated.

mike
 
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No. Won't work. You have coarse spline. 79 is fine spline. Nothing will fit. I've been here 7 years, nothing works here...(sorry, got off track,) If you want to street drive, find a matching 79 rear axle and install em both. This is a major deal, by the time you set up the ring and pinions, swap this one to that one, make the birfields work, etc. more trouble than its worth! Can you do this work yourself? Do you know someone knowledgeable who can help? If not, this is a disaster waiting to happen.
 
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lx450landcruiser said:
ok so how about if i take my stock 71 3rd member out i think its called a 3rd member? basically the pumkin out and put in in the 79 axle would that work? or is this way more work then i think? Like i said this is new stuff to me so any help is appreciated.



mike

I think if you take the 79 axle and use the parts just as if you did a mini truck disc conversion that you can make it work. only difference is that you will have the vented discs and larger calipers from the fj40 that most like better. There is several articals in the tech section of this forum that covers the mini conversion
 

lx450landcruiser

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i guess its the birf swap or no go. thats alright i guess its not that it needs the disk brake front end just thought it would make it more attractive to the buying market.
 

lx450landcruiser

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Texx said:
No. Won't work. You have coarse spline. 79 is fine spline. Nothing will fit. I've been here 7 years, nothing works here...(sorry, got off track,) If you want to street drive, find a matching 79 rear axle and install em both. This is a major deal, by the time you set up the ring and pinions, swap this one to that one, make the birfields work, etc. more trouble than its worth! Can you do this work yourself? Do you know someone knowledgeable who can help? If not, this is a disaster waiting to happen.

Im not trying to be ignorant and im not planing on doing anything im not qualified to do im simply asking about all possibilities. i had a friend do this same conversion and i wasnt sure if there was a diff between a 78 and a 79 ect... well now i know.
 

Yoda

 
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I did this swap. A 4/79 Axle into a 71.

I changed the pumpkin to retain the 4.11 gears. Also to match the holes on the driveshaft.
The brake line on the 71 comes from the left frame, the 79 comes from the right frame. (I changed the tubes on the axle to match my truck....involved bending, cutting and double flaring the tubing)
 
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