maxamillion2345
Franken-80
I really am glad to see people breaking the mold.
Double triangulated rear 80
- Thread starter nukegoat
- Start date
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that's awesome. If I end up keeping my rig for the long haul I was seriously considering a full on re-do of the rear suspension. while it works great at stock height, it doesn't work that great with a lift. I would also like to see some pics of the truss over the axle. BTW, what shocks are you using?
nukegoat
Should have bought a Jeep
- Thread starter
- #25
I don't, unfortunately. I'll try to get some this weekend. The oem axle uppers are strong enough to withstand the tension and compression required to prevent axle wrap (obviously) so I gusseted them to provide lateral stability. The passenger side is just barely taller than the pumpkin and welded to it AND it's a fully boxed member so the gussets are just for peace of mind.
The truss, then, attaches to those factory mounts and spans across the pumpkin. It is raked back a bit and moves back to where it would barely interfere with the stock track bar. The wishbone is pretty much like any other triangular wishbone. Uses bushings at the oem frame upper mounts because in a wishbone, as you know, the only way it needs to articulate is rotating about an axis.
nukegoat
Should have bought a Jeep
- Thread starter
- #26
Yeah, so the big challenge is packaging the uppers. If you run a regular ol' 3-link w/ panhard, you can probably find a way to get a longer upper link near the exhaust somehow, but the geometry just doesn't really look great IMO with that setup. I also much prefer a double triangulated setup for a non-steer axle. You could do a double triangulated 4-link instead of a wishbone, but it would more than likely require spherical bearings or cartridge joints in the OEM frame uppers, which I didn't really want to do.
The upper doesn't come in contact with the forward X member? How much lift to you figure you have? As you know, there was no way I was getting the upper links to clear without bending them to clear the forward coil spring x member and I am shooting for 21"-22" to the bottom of the frame just behind the t-case x member. Not knocking what you did, I think it's bitchin' and I considered doing this, I just couldn't get the clearance around that f'ing x member.
2fpower
SILVER Star
Deleted...
Hey Nukegoat, been lurking on your threads for some time. Enjoy your passionate discussions of suspension, and excited to see how yours is progressing.
Hey Nukegoat, been lurking on your threads for some time. Enjoy your passionate discussions of suspension, and excited to see how yours is progressing.
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nukegoat
Should have bought a Jeep
- Thread starter
- #29
Bout 5" of lift. My uppers are like 19.5" long in that axis. I use the OEM crossmember and OEM frame mounts for my upper. I don't need to go under it. Longer uppers aren't required to make the system work. Try plugging away in the calculator with my numbers and play around with it as it travels.
Nukie, you have a small bodylift(gas tank just above frame rails)?
I'll give you credit right now. Gonna borrow a couple potential ideas from this. Nice work buddy
I wish I had a spare rear housing to work with, while the vehicle was still driving.
I'll give you credit right now. Gonna borrow a couple potential ideas from this. Nice work buddy
I wish I had a spare rear housing to work with, while the vehicle was still driving.
nukegoat
Should have bought a Jeep
- Thread starter
- #31
No body lift. Getting the exhaust routed over the frame and a crossmember under the frame was tight.Nukie, you have a small bodylift(gas tank just above frame rails)?
I'll give you credit right now. Gonna borrow a couple potential ideas from this. Nice work buddy
I wish I had a spare rear housing to work with, while the vehicle was still driving.
Here's how you get a crossmember under the gas tank - The 1/4" plates that weld to the frame are thick enough to allow the bolt-on crossmember to clear the gas tank skid *right* where the forward retaining strap is. The straps run perpendicular to the vehicle so it works perfectly. You can probably see in my pic that I also notched out an inch from the 3x3x0.1875 square crossmember piece where it runs under the transfer case just to provide a little extra clearance under droop (and to access the u-joint grease fitting and so on)
Not to get too engineerdy but the loads that the crossmember takes are primarily trying to sheer the bolts and welds off the frame. If you were to land the vehicle weight on the crossmember, it would be mostly trying to bend it (which won't happen, even with only a 2" tall structure) or try to peel the welds off the outside of the frame (which is also a tall order).
To be fair, if you're landing the entire vehicle weight on that crossmember in the center (right between the gas tank and xfer case output yoke) then you would have been in a very bad way without the crossmember protecting anything. So it's actually better from an armor standpoint, IMO.
Here's another shot about midway through construction. You can see the plates that weld to the frame sitting on top of the crossmember in its rudimentary form:
nukegoat
Should have bought a Jeep
- Thread starter
- #33
Just took it out for a day at Hollister. The thing climbs much better and is far less leany off-camber. It's flexy as heck until the shocks reach their limits, and driving it on the freeway was no problem even with no front sway bar. Super win! I think this may be more satisfying than my work on the front... Not too pricey either.
Pics!!!
(Pretty please) I've never seen an 80 in tank trap, this should be cool!! 
(Pretty please)
I've never seen an 80 in tank trap, this should be cool!!
nukegoat
Should have bought a Jeep
- Thread starter
- #35
Some pics. Climbing through those pipes would be unthinkable before with the 80s bull. Yes I know the truss is ugly. Going to probably change the aesthetics of it a bit and gusset the underside. It doesn't need it but it wouldn't hurt and it'd make it a bit less goofy looking.
nukegoat
Should have bought a Jeep
- Thread starter
- #36
Tank trap is stupid. It's just a lean and grind climb. No real solution other than that and hammering down. There's an 80 on Craig's list on 35s that did it. Looks haggard on the entire driver side. Not fun to mePics!!!
(Pretty please)
Tank traps good for nothing but poison oak and removing paint off the entire side of a vehicle.
Don't worry about the truss, etc. nobody's gonna hold it against you since you were clearly pioneering something and built it as such.
Redo it later once you get it all dialed(seems like you might be at that point).
nukegoat
Should have bought a Jeep
- Thread starter
- #39
Thx for the encouragement! I will probably fix the way it looks at some point but it is a good proof-of-concept.
I am at a crossroads with the front axle. I need the width that spacers give me to avoid rubbing on everything when I flex, but the scrub radius is killing me. Adding hydro assist seems dumb unless I want to get high steer, hellfire knuckles and GM 1-ton TREs, which would be a good idea but then I eternally worry about the 8" ring gear being too small for reversing when bound up. I'm not really concerned about the axle shafts, fortunately, but everything else is getting close to the limits. So... I'm reluctant to throw another 1.5-2Gs into a project just to improve steering marginally. I'd end up re-linking it and burn a hundred hours in the process of it all.
But then I look at my gearing options for domestic axles, and the only overlap I'd consider with Toyota is 4.88, which is higher than the 5.29s I currently run and would require re-gearing the rear. Unless I had a custom housing built with a Ford 9, then I could run 5.29s but it'd be a low pinion and I'm sort of a believer in CVs in the steering axle. Anyway, fixing the strength issues that I've reached in either axle (I'm not breaking stuff yet, which is nice) is a very expensive step-function that I'm not sure I want to deal with.
What I really need is someone to sell me their widened hybrid 9.5/80 axle. You know, for science.
Something we need to put their heads together on to figure out is a way to get bigger spindles on the rear and EDM the side gears in the carrier to accept 35-spline stuff. But then I worry about the pinion being a bit undersized. So it goes.
I'm trying my darnedest to figure out how to get us a doubler. It requires a 95 or newer tranny though(a343)? Guessing by your grill, you fall into that group.
Maybe once we can crawl properly the thing won't need to be 'bumped' over everything and finesse will save the downstream drivetrain parts.
I'm 32 spline in the rear(or at least half parts are on the way).
For domestic axles, a dodge60 is 67.5(probably what you have with the spacers). A dually ford70u is 72.5, but when one side is cut off to make it offset you have 65 or whatever you desire.
Maybe once we can crawl properly the thing won't need to be 'bumped' over everything and finesse will save the downstream drivetrain parts.
I'm 32 spline in the rear(or at least half parts are on the way).
For domestic axles, a dodge60 is 67.5(probably what you have with the spacers). A dually ford70u is 72.5, but when one side is cut off to make it offset you have 65 or whatever you desire.
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