Hey Also, I forgot to mention earlier with the front driveshaft. The 60 series front drive shaft uses different ujoints than the 80 series front. The only reason i was able to swap over my diff flange end of my old drive shaft is because my front driveshaft is a custom front driveshaft and not a stock 60 series driveshaft.
The 80 rear diff uses the same pattern as the 60 rear diff.
If you still have the original 60 series front driveshaft youll need to swap over the actual diff pinion flange from you 60 series or buy one from Cruiser outfitters or valley hybrids.
That being said, youre going to need to lengthen or shorten your front driveshaft anyways doing this swap. Lengthening a driveshaft is $250-300 and buying a whole new one is like $500 or so and you get new ujoints and a fresh slip yoke.
My front driveshaft was built by JE Reel. I had them use toyota mini truck rear ujoints (1985-1995 pickup/4runner) and ends because they actually have more operating angle than any Spicer ujoint and any of the other land cruiser ujoints. It just so happens that the 80 series has an 8 inch front diff and uses this same ujoint in the front driveshaft only. That is the only reason i was able to just swap over the end of my drive shaft to fit the 80 series diff.
The 60 series diff bolt pattern is 66x66mm with 11mm holes. The 80 series and all mini truck diffs have a 60x60mm bolt pattern with 10mm holes. So if you order a new driveshaft, youll want to get 60x60mm hole spacing pattern on which ever end you put at the diff. I put the thicker end at the diff and the smaller slip yoke at the tcase, so my slip yoke side is 66x66 and my diff side is 60x60.
To make it even more complicated. The 80 series front drive shaft uses M10x1.0 driveshaft bolts and the 60 series uses M11x1.0 drive shaft bolts and M11x1.0 studs on the tcase output flange. So youll use 11mm nuts and washers at the tcase, and 10mm driveshaft bolts/nuts/washers at the diff.
10mm drive shaft bolt - 90105-10424
10mm washers (this comes with 4 washers) - 90560-10H00
10mm nut - 90178-10006
So long story short, want to keep your 60 front drive shaft? change the pinion flange on your 80 front diff to a 60 pinion flange.
Want to get a better driveshaft? Call JE Reel and have them make you a front drive shaft with a 66x66 slip yoke side for your tcase with 11mm holes and a 60x60 diff side with 10mm holes. Ask them to use Matsuba 29x49mm ujoints or if they cant get Matsuba, theyll probably use Neapco 1-1612 since they are a neapco dealer. Neapco is good stuff. The yokes on the mini truck drive shaft ends also clear the 4l60 oilpan if you have that and flex a lot more than the 60 ujoint or 1310/1350 spicer ujoints. I wouldnt use tom woods for the front, theyll use 1310 joints. If you are using a 4l60e transmission youll want to get smaller diameter thick wall tubing. I think my tubing is 2 inches diameter with .120 wall to clear the transmission oilpan. If you have the the h42, h55f, or whatever the fj62 auto is, you dont have to worry about this.
Heres my front driveshaft from je reel with the end swapped over. the dirty shaft on the left is the 80 series drive shaft
Front driveshaft clearance for mini truck ujoints on the 4l60e.
