60/80 rear steer axle?

Mar 16, 2016
vancouver, bc

I've seen a couple guys on here talking about rear steer 60/80 axles. Wondering how they've held up.
I've got a 6.0L YJ truggy on 60 hybrid axles and 42's. Front flipped DD and widened 3", and rear centered and still on IFS SF shafts. I'm of course snapping SF shafts (right at the spline where it tapers). Been thinking about what I want to do next.
I can either FF the rear as it is, or drop in an 80 rear, or just turn the rear into a steer axle using 60 or 80 outers. I've got a lot of mixed reviews on using the 60 outers on the rear though. General consensus is that it'll blow birfs constantly. I'm not sure what to believe though, as 99% of guys who are blowing up 300m birfs, I also notice forgot to shim knuckles, or they're using steering stops for steering limiting instead of a ram, or 20 other setup failures. I'm not sure I trust any of the "failure" guys, as every single time I look at the failure, it's installation issues. I haven't yet seen a 60 steer axle with a 300m birf that was properly setup fail, so I just don't have anything for reference.

Now I'm also a bit heavier at 4600lbs with gear and driver.
I figure most people agree that going to FF will net me nearly double the torsional strength over SF, which does jive with my FEA simulations (FEA said 180%) and then we're going from SF to FF so no weight on the shaft, which should help a bit, so I figure my weakest link there is probably going to be the birfs. I've been waffling on what to do about this for a couple weeks. I could just FF it and see how she do, but seems a shame to not take this opportunity to just steer it as well.
I was thinking either 60 or 80 outers with 300m birfs/shafts.

What are your thoughts? FF likely to survive? 60 or 80 knuckles/birfs survive? Would the steering outers make it significantly weaker? Would an 80 knuckle be as strong as a straight FF shaft?

For reference, the SF rears have held up to very abusive street, evil FSR at stupid high speed, and moderate trails, but they failed on what is largely considered to be a buggy trail. Got bound up, light throttle with very little wheel speed and she snapped. This trail is barely a challenge for my rig now, but there's one spot where everything just sorta conspires against you and you end up with the rear passenger bound up a bit. Probably 3/4 of Jeeps that attempt it, snap. toy 8" axles that actually clear the obstacle, might do so without breaking 30% of the time. Guys on tons still break there as well (but they're usually driving like dicks).
I don't pin it on climbs, but you know how PNW wheeling is. All slick/snotty and then you hit the sharp rocks and grab.
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