Driveshaft flange question - going from '66 to '76 flange (1 Viewer)

[Oregon FJ40]

I have read through multiple threads on here but have yet to find an answer. I put a front axle from a '76 40 into my '66. I did not know until yesterday they had different bolt pattern... now I know. What I'm curious is if anyone knows if I can just replace the front flange on my original driveshaft with one that fits the new axle. I.E. replace it at the ujoint. Or would it make more sense to get a front driveshaft for the '76 and have a driveline shop frankenstein the two together? Any input would be appreciated.

-Mike

 

[charliemeyer007]

Interesting. A good drive line should be able to fix you. There is a lot of spline in the slip joint. Myself I would make an adapter plate of like 3/8" good steel, drill and tap it to both patterns and high strength Loctite good bolts in from both sides if the patterns don't conflict. Sorry my vision is poor today and I can't really see you pic very well.

 

[peesalot]

Buy a flange from WFO or Cruiser Outfitters that bolts on and away you go, or the 1/2 & 1/2 drive line works if you have both.

 

[Living in the Past]

66 was the small three speed flange. Around 69 flange for three speed change. Four speed used a different one 1/74 to 8/84.

 

[pb4ugo]

I believe you can just swap diff pinion flanges. I think the pinions referenced use a solid spacer and not a crush sleeve. Maybe someone can chime in to confirm. The driveshaft bolts are special. Using improper bolts are a bad idea. The 76 driveshaft maybe a different length because it has a 4 speed.

 

[Oregon FJ40]

Buy a flange from WFO or Cruiser Outfitters that bolts on and away you go, or the 1/2 & 1/2 drive line works if you have both.

Cruiser Outfitters lists two different parts numbers for the early-74, and the 74-84 u-joints. My concern is that they are different sizes and the newer flange will not fit on the earlier u-joint. That would definitely be the cheaper of the two options. Probably worth just ordering the part and trying it, and if it doesn't fit, return it or keep it for a spare down the road.

66 was the small three speed flange. Around 69 flange for three speed change. Four speed used a different one 1/74 to 8/84.

Correct. That is what I'm trying to problem solve by converting an older driveshaft. Also uses different sized bolts.

 

[Mark W]

Swap the flange and go. Both the '66 and the '76 used the coarse spline pinion so the flanges will interchange.

Mark...

 

[Oregon FJ40]

Swap the flange and go. Both the '66 and the '76 used the coarse spline pinion so the flanges will interchange.

Mark...

Just reread this. I'd like to not mess with the pinion if possible

 

[B y r o n]

Scratch this idea, 1/74 u-joint changed so apparently won't work. Differential flange replacement would be the way to go. Why mess with the differential yoke, simply change the driveshaft u-joint flange (providing they use the say size u-joint).

 

[Oregon FJ40]

Why mess with the differential yoke, simply change the driveshaft u-joint flange (providing they use the say size u-joint).

So you think changing the pinion flange is the way to go? Would that require any readjustment of the gears?

 

[Mark W]

Just reread this. I'd like to not mess with the pinion if possible

Why?

Mark...

 

[pb4ugo]

Loosen a nut swap flanges and tighten the nut. Torque to spec and stake it.

 

[Mark W]

So you think changing the pinion flange is the way to go? Would that require any readjustment of the gears?

No.


Mark...

 

[Oregon FJ40]

Why?

Mark...

I thought that was a much larger job than what pb4ugo just posted. actually sounds pretty minor.

 

[Mark W]

I thought that was a much larger job than what pb4ugo just posted. actually sounds pretty minor.

about as minor as it gets.


Mark...

 

[B y r o n]

While you are in there replacing the pinion flange, I'd replace the seal as well.

 

[peesalot]

Was not aware the spline is same, thought the 76 would be fine.
What happened to the 1/2 & 1/2 drive line idea ?

 

[Oregon FJ40]

Was not aware the spline is same, thought the 76 would be fine.
What happened to the 1/2 & 1/2 drive line idea ?

A new flange looks to be about $50 which seems pretty nice, especially since I initially thought changing that flange required pulling a whole bunch of parts apart. I can do the driveshaft combo if necessary, but from my google searches, I'm gonna drop at least a few hundred for the '76 era used driveshaft, then paying a shop to cut both apart and combine them. The '66 and '76 do appear to have difference sized u-joints, so I cannot just replace the front flange on the driveshaft

 

[Oregon FJ40]

Searching for the pinion flanges today, I'm seeing multiple sites selling 27 spline pinion flanges for the early-68 (cruiserteq, fjparts, sor.....). So just to be safe I'm going to pull the flange I have off to make sure I order the correct one.

 

[pb4ugo]

Can't you just swap the 66 to the 76?
I think late 78 or 79 went fine spline.