Front Axle Identification

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Joined
Jul 14, 2012
Threads
44
Messages
118
Need some assistance in identifying the year of my FJ40 disc brake front axle. Are there any tell tails that will aid me? Im planning on doing a complete rebuild on it. Everything is stock and has Warn Fine Spline hubs so I believe its made after mid-1975.
 
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Need some assistance in identifying the year of my FJ40 disc brake front axle. Are there any tell tails that will aid me? Im planning on doing a complete rebuild on it. Everything is stock and has Warn Fine Spline hubs so I believe its made after mid-1975.
The only differences are spacing on arms and lower bearing caps. 78 Has 4:11 fine spline pinion. 79-84 are 3:70 ratio.
76-78 have the smaller birfields.
Rotors also changed around 79
 
You theoretically could also have a knuckle swap. Are your rotors vented? Are your two knuckle arms mirror images, or does one look like it might have had something cut off of it?
 
On the left side of the 3rd-member (looking at the pinyon) there are the numbers 4111-60011. On the calipers there is 7 7w then a 4 below that as well as S12+8. The rotors are vented. Both knuckles are identical. Some axle hub/locking hub work has been done in the past as there are markings of the letter "L" and "R" on the correct respective sides. Previous owner believes it is a 4:11 but never checked.
 
Pics would help. I think there are 2 different types of rotors for an FJ40. One uses 6 bolts to hold the rotor to the hub and the other uses the wheel studs to hold the rotor to the hub. Knuckle ID wise there are large and small pattern knuckles. Go to the FAQ section at the top of this section and scroll down to frt ends and read the 1st two threads. 1 on lockouts and one on knuckles. You're probably gonna have to remove the rotor/hub assembly to determine which rotors you have.

Edited for accuracy. Thanks @65swb45
 
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Pics would help. I think there are 2 different types of rotors for an FJ40. One uses 2 bolts to hold the rotor to the hub and the other uses the wheel studs to hold the rotor to the hub. Knuckle ID wise there are large and small pattern knuckles. Go to the FAQ section at the top of this section and scroll down to frt ends and read the 1st two threads. 1 on lockouts and one on knuckles. You're probably gonna have to remove the rotor/hub assembly to determine which rotors you have.
The earlier hub housing used SIX bolts to hold the rotor on. The holes for the six are readily visible with the wheels removed.😉

Funny anecdote. On my first trip back east to attend Fall Crawl, @StaleAle delivered me to Iron Pig Off Road. Lance had just recently installed a rock garden behind the shop to test out modifications and have some localized fun. @FJ60Cam let me try out his FJ62 rock buggy up until someone screamed at me to STOP because something was horribly wrong.

They pulled the buggy off the rocks and back to the shop entrance, where they gathered around, all scratching their heads. It seemed that someone had noticed that when I hit the brakes, a rotor had stopped moving…but the tire was still turning. They expected the wheel to fall off the truck.

At a dead loss, I explained to them my theory that somewhere along the way someone had expeditiously replaced the factory FJ62 hub with an early FJ40 hub, which could have the bolts fail without losing a wheel.

I had instant street creds. 😉
 
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I have a knuckle kit for that.😉
 
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