40 vs 55? (1 Viewer)

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alberta canada
Hey, I have a ‘78 fj40, 2f, 4 spd, stock diffs i think 3.70:1. I have a chance to pick up a junker ‘74 fj55, all stock, F motor, 3 speed. Is it worth my while to grab it for some parts for my 40? I’m trying to search some info, but it’s very convoluted. I’m gathering that the rear diffs should be identical to my 40, except would have 4.11s, and the axles are the same? I’d love to swap to 4.11s, and carry a couple spare axles off road for sure. Are any other driveline (or otherwise) parts interchangeable between the two? It’s pretty rough, but maybe part some 55 pieces too and recover a bit of cost...
thanks!

mike
 
Your '78 should have factory 4.11s. 3.70s started in 1979. The FJ55 rear axle should be the same, except the pinon flange may be smaller for the 3 speed transmission. You'd be in a much better position if the FJ55 were (say) a '76, but it's not.

There will be some useful stuff on the '55 you can swap to your '78, but not a ton of it. If the '55 is cheap enough, you could just get it and part it out.
 
Ok thanks. I have to recheck my 40, I was sure it was 3:70 for some reason.
this 55 is cheap for sure, maybe as long as there’s a market, I could turn the whole thing back into a bit of return.
thanks!
 
Ok thanks. I have to recheck my 40, I was sure it was 3:70 for some reason.
this 55 is cheap for sure, maybe as long as there’s a market, I could turn the whole thing back into a bit of return.
thanks!

IIRC 1978 was the desirable year for 4.11s because they were fine spline pinions, prior to that coarse spline.

The F head should work on your 2F to create a higher compression 2F.
 
Here’s my vin plate, says H41-K052.
Does this not mean 3.70:1? 🤔

5E121467-BDFA-49AA-8FCA-1C90C6C28322.jpeg
 
To be sure you should pull the rear diff cover and count the ring and pinion teeth to confirm the ratios. Sometimes the side of the ring gear may reference its ratio too.
There are a lot of FJ55 parts that are no longer available, so there is a market for a lot of the trim, interior and body parts. If you scroll way down on the 1st page on this website you'll find FJ55/ Iron Pig section. They have their own for sale section.
 
‘78 should be 4:10 as mentioned above. 3:73 began in ‘79 as an effort for Toyota to improve fuel mileage so the purpose built factor began to go to the wayside. In speaking to folks with ‘79-83 rigs most will say they saw no mileage improvement, some have said 1 mpg, maybe.
 
Buy the 55 and bring it back to life. Always sad to see a 55 go to pig heaven.
 
‘78 should be 4:10 as mentioned above. 3:73 began in ‘79 as an effort for Toyota to improve fuel mileage so the purpose built factor began to go to the wayside. In speaking to folks with ‘79-83 rigs most will say they saw no mileage improvement, some have said 1 mpg, maybe.
And yet my ‘78 isn’t. Not sure what’s up with it.
 
Well mine is a 10/‘78 manu date and 4:10, perhaps later units in ‘78 had already gone the way of the ‘79, or they were changed by a PO? I am never surprised by what PO’s do🙄
 
Well mine is a 10/‘78 manu date and 4:10, perhaps later units in ‘78 had already gone the way of the ‘79, or they were changed by a PO? I am never surprised by what PO’s do🙄
Beats me, my VIN decodes as Feb '78. If the VIN plate matches what the diffs are, Id say the PO didn't change anything.
 
Beats me, my VIN decodes as Feb '78. If the VIN plate matches what the diffs are, Id say the PO didn't change anything.
That is weird as it should have come from the factory with 4:10 geared axles. Maybe @Living in the Past can chime in on this.
 
That is weird as it should have come from the factory with 4:10 geared axles. Maybe @Living in the Past can chime in on this.

1/79 when the tub changed US market started the 3.70:1 diffs to improve the mileage. Same with the FJ55 which really didn't change much as his was going to be replaced 8/80 with the 60 series. Our FJ60 always the 370 diffs. Wasn't until the FJ62 with the automatic with OD did we get 4.11s again.
 
1/79 when the tub changed US market started the 3.70:1 diffs to improve the mileage. Same with the FJ55 which really didn't change much as his was going to be replaced 8/80 with the 60 series. Our FJ60 always the 370 diffs. Wasn't until the FJ62 with the automatic with OD did we get 4.11s again.
🤷🏼‍♂️ Ok so what’s up with this one? I don’t get it.... any ideas? I’m in Canada, maybe Canadian ones were different? Or is it imported or something? Thanks for the replies!
 
🤷🏼‍♂️ Ok so what’s up with this one? I don’t get it.... any ideas? I’m in Canada, maybe Canadian ones were different? Or is it imported or something? Thanks for the replies!
Oh never mind, just actually read your reply lol. 🙄 No wait. Read it again. Mine is a 02/78 according to the vin. And it has 3:70 gears. Wtf.
short story I guess, I’m passing on the 55, I don’t have time to part it out and where I’m at I doubt there’s a market for it.

mike
 
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Quick search shows Canada has listing for both 3.70 and 4.11 diffs. US market shows up to 1/79 only 4.11 and 1/79+ only 3.70. this only goes back to 3/69. In the early 60s both were available will most 4.11s being imported. During this a third even higher gear option was offered. Long story but almost scored a pair of those.
 
Quick search shows Canada has listing for both 3.70 and 4.11 diffs. US market shows up to 1/79 only 4.11 and 1/79+ only 3.70. this only goes back to 3/69. In the early 60s both were available will most 4.11s being imported. During this a third even higher gear option was offered. Long story but almost scored a pair of those.
Quick search shows Canada has listing for both 3.70 and 4.11 diffs. US market shows up to 1/79 only 4.11 and 1/79+ only 3.70. this only goes back to 3/69. In the early 60s both were available will most 4.11s being imported. During this a third even higher gear option was offered. Long story but almost scored a pair of those.
Thanks 😊
I confused myself there lol.
 
Where in AB is this located? If you are passing, I know there are a few pig owners around Edmonton and Calgary who may be interested.
 

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