Builds Amateur Franken40 Build

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RCV will build custom length axle shafts. HTH
 
RCV will build custom length axle shafts.
Haven't looked into them too much but I don't believe they do for the 80 axles which have the built in flange on the end, not just a straight shaft with splines on either end. I'm thinking a dana 60 may be the better, more cost efficient option. Then 6 to 8 lug adapter/spacers on the 80 front.
 
You are correct. I called them and asked if they do the shaft with flange. They did say no. They will do custom length shafts but then you have to run the drive flanges.

I have a 60 FF, same shaft dimensions, just different lengths
 
I'd be tempted to build a 9.5 front if I went that route since I'd have the axle sitting there. Have a 60 housing I stripped and used the knuckles on the 40 axle that I probably won't get my money back on. Should really just rebuild it and swap for the rusty axle on my 80. The extra clearance up front with the 8" would would be nice for getting over stuff, though.
 
I didn't realize that every single wheel adapter/spacer out there is complete junk, so forget about that. I don't want to die.

Looks like there are 6x5.5 hubs available for the FF 14 bolt, add a Toyota pinion flange and should be good to go. Probably shave it. Then run my 80 front axle, maybe with a small spacer. Not making a custom axle will save a lot of time. Pretty much all factory parts, too.
 
Coming back around to the idea of a centered 9.5. RuffStuff housing, cut to length and press-on and weld full float flanges from front range (RuffStuff used to make but not any more apparently), which then use mini truck solid front axle spindles, hubs, and brakes. Can use a stronger drive flange instead of locking hub. Then get custom length rcv shafts. Would need a parking brake solution. I know there are kits for adding one to back of an rf1a. I suppose I could rob the spindles and hubs from the FJ60 knuckles I already rebuilt.


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Snagged a vf2a out of a '96 4Runner for $50. Will be donor for planetary gears for the eco crawler. Will be picking up a pair of gear drive cases next weekend as well. Then just need to find an r150f.

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Waiting to hear back from NWF, it's not clear if the rf1a output version of the eco crawler will work with different gear sets. The vf versions use a custom input shaft and gear on the rear case. NWF site says 23 spline case will work, which would lead me to believe there is no replacement input shaft because the new shaft would just be whatever it needs to be. It may just use an internally splined sleeve/collar to mate to the rf1a. Otherwise, it would use a custom input shaft and gear like the vf versions and would be stuck with stock gearing. Would really like to run 4.7 gears in the rear case.
 
Correction. That measurement was based off my H42 with a 60 top plate. 40 shifter is about 3.25" further forward. So would actually be about 10.75" back. I'm thinking that will be too far back. Will need to do some thinking.

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if the 40 h42 is too far back why not just use a 60 top plate and push the engine forward a bit more? is there not enough room to go that way?
 
if the 40 h42 is too far back why not just use a 60 top plate and push the engine forward a bit more? is there not enough room to go that way?
That was the plan if I was going to use the H42/H55F, but I'm going to be using an r150f now with the change in engine. I was just using the original h42 shifter location as a reference to see how the r150f shifter location compared (further back. I originally measured the 60 top plate when I should have measured the 40 one.
 
gottcha. i did the 60 top plate swap when i put my 350 in. it gained me a bunch of room so i won’t have over heating issues hopefully. thought it might be helpful but you’re on a different path now!!
 
Aqualu also got back to me, and I can get the unwelded 10" stretch frame rails for a pretty reasonable price. They are mandrel bent and look pretty thick. I think it will be a worthwhile investment, and the geometry of the frame should work out better for a linked suspension especially if I move the axles. Plus, it will be really nice dealing with fresh steel and no rust sandwiches. I'll need to prioritize my purchases, this part of the build is getting pretty expensive and I have already sold off most of the value parts I don't need. I'm hoping to at least get the om606 mounted up so I can build the front suspension this summer. Probably stuck doing bodywork after that, want a complete drivetrain before I build the rear.

Checked with inspectors already and titling with this frame won't be an issue in MN, just need to keep invoice for the frame and it will be getting a reconstructed title.

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Have an assortment of cases to play with now. Will probably sell the forward shift case. If anyone is interested in a Chevy to rf1a adapter, let me know. I have no use for it.

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Some rough measurements for number crunching driveline lengths.

2F front of fan to bellhousing mount - 36”
H42 bellhousing - 7.5”
H42 length- 11”
Split case front to rear flange - 8.75"
Split case offset - about 9.5”
Total length from engine rear to rear flange - 27.25"

OM606 front of fan to bellhousing mount - 32.5”
Transmission adapter- 1.5”
R150f front of bellhousing to rear - 26 ⅛”
Ecocrawler length - 6.35”
RF1A front of case to rear flange - 12.5”
RF1A offset - about 6.5”
Total length from engine rear to rear flange - 46.5”

Rear axle will be moved back about 3 inches. OM606 can be moved forward 3.5 inches.

With OM606 shifted 3.5” forward to put the front of the engine fan in the same location as the 2F, the rear transfer case output flange will be about 15.75” further back than on a stock 40. With a 10” stretch like I was thinking, and moving the rear axle back 3 inches, my rear driveshaft will be 2.75” shorter than a stock 40 (a little under 19”). I’m no expert, but I am thinking this is too short for the travel I am hoping to get out of this thing. Will likely end up doing a little more stretch than that.

Another thing I noticed is the RF1A front output is offset about 3” less than the cruiser case. Shouldn't be an issue.
 
Getting a lot of great ideas and inspiration from this build. I may end up doing something similar for the rear bumper. The front tube fenders and grill hoop are similar to what I've been thinking as well.

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I am hoping to put the order in for the aqualu rails in the next month or so, this summer will mostly consist of building the frame and bodywork, and collecting a few more parts.

After much more research and discussions with @fjdiesel, I have abandoned the R150/ecocrawler/rf1a gear case/centered 80 rear axle plan. The power comes on too suddenly with the 606 for manual to work well off road. Too jerky. I am instead going to run an 8HP75 8 speed auto and atlas 2 speed. The 5:1 1st gear will make for good crawling with the atlas, and 8 speeds will give a good range to choose from without needing to select between dual cases. There is also a clutch emulator for this transmission that I am pretty excited about trying. I will also be selling my 80 axles in favor of super duty axles. It's a shame, but the Toyota axles are expensive to build strong. That, and the adapter to run a split case makes it actually a bit more affordable to run an atlas and tons than the split case and built 80 axles. Won't be a whole lot of cruiser left in this thing when I'm done with it. Now, to sell a bunch of parts I wasted money on... Lol.
 
Getting close to a rear winch bumper design plan. Have some crude SketchUp drawings to help visualize. The bumper/cross member will be made from 3x4x1/4 rectangular tube. The Ruff Stuff clevis shackle brackets on the other bumper I was originally using for inspiration were unfortunately discontinued just a week or two before I was planning to order them and there are none left. Not the end of the world, they would probably have gotten in the way of the swingout tire carrier. I have opted to utilize the hitch receiver as the main recovery point, but may weld something else into the frame later on.

The winch plate is actually from a big ugly weld together bumper kit for a Silverado a buddy abandoned at my place after changing his mind, it will be of much better use here.

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First bit of bling showed up today:
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I will be ordering the aqualu 18" stretch frame rails soon. As it turns out, the 10" stretch frame is made by adding 10" straight off the back of the regular 40 frame. Which, works fine for most, but I am planning on also shifting the rear axle rearwards a bit. The 18" stretch frame gets all of its extra length in the middle, flat portion of the frame. While 18" is a bit more stretch than I probably want, I can probably shave a few inches off the back still or move the front cross member where the bib mounts back a few inches, as my body and all of my body mounts will be custom anyways. Axles will be much wider, and front axle is getting shifted forward a bit anyways so not concerned about frame/tire interface.
 
Coming back around to the idea of a centered 9.5. RuffStuff housing, cut to length and press-on and weld full float flanges from front range (RuffStuff used to make but not any more apparently), which then use mini truck solid front axle spindles, hubs, and brakes. Can use a stronger drive flange instead of locking hub. Then get custom length rcv shafts. Would need a parking brake solution. I know there are kits for adding one to back of an rf1a. I suppose I could rob the spindles and hubs from the FJ60 knuckles I already rebuilt.


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That is basically what i have for my rear axle . Diamond Housing Full Float RCV shafts with Drive flanges
 
That blue one looks kinda like the blue one I have

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That is basically what i have for my rear axle . Diamond Housing Full Float RCV shafts with Drive flanges
I'm still not 100% opposed to this route, but if someone buys my 80 axles this summer I will be going with 1 tons. Beefy enough I wont really need to upgrade them, wide, stronger brakes, more weight down low. I am not impressed with my 80's brakes even with just 33s. But, they still need some work. And the 40 should be much lighter. I am, however, planning to eventually be towing a small teardrop style trailer. Dana 60s may be a bit overkill for the 37s I am planning to run, though. Bigger diffs will hit rocks more. When I looked at it a while ago the cost of building the toy axles looked pretty comparable to just going with tons and not worrying about breakages as much. Not committed yet.
 

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