Upgrade to 4340 Chromoly Shafts?

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I'm starting to order the gears and lockers for the '84. Currently, everything is stock (60,000 miles). I don't want this to spiral out of control. But, I don't want to overlook the obvious upgrades... especially when the labor is already accounted for with this work. With that stock 105hp 22r, 5-speed, 4.88s and 33s, should I worry about breaking stock axles? And if so, what are the go-to brand(s) for these? There are a bunch of manufacturers out there. I'm assuming a few are the same under different names. Also, a few look to be out of stock with vague ETAs. Marlin shows them, but looks like they're out of stock no longer selling them.

Oh, it's probably worth noting, the purpose of the lockers, winch, sliders is NOT to barely make the hard trails; it's to do moderate trails without damage. I've served my time on my back under trucks on trails... I like to think I've matured ;)
 

pappy

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I've witnessed stock birfs fail even on 31" tires and open front diff but it was in a tough spot and full turn. Actually, every time I saw stock ones fail was in a full turn. I think the risk of failure is definitely higher locked.

I have TG dirty 30's and I've had Long's in another truck on 35's without failure for years. Both with Aussie lockers. The chromo hub gears are required to get warranty.

RCV is the way to go. Not cheap upgrades but you'll never break them. Locked or not.

If you have any concern that you could be stranded because of a broken birf, RCV's will ease your mind. I guess you have to decide if your use of your truck warrants the upgrade.
 

ntsqd

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Back in the days of the ORC email list we tallied things up and put together some RoT's about this. Let me see if I can recall what they all were.

How to fail a stock Birf:
Tires bigger than 33-10.50
Gears lower than 4.11
Any doubler
Any true locker (LSD's may not apply - depends)
Full Lock on the throttle with any one of the above

I ran 4.88's, 33-9.50 and 33-10.50's, no doubler for ~125k miles and never failed a front axle part. Oh, sure I hammered the steering bearings to the point of severely notchy steering several times, but never failed a Birf or an axle shaft. I also don't beat my trucks against the rocks like some do.

If you're really beating on the truck then all bets are off and you should be looking at D60's at the least. If you're not doing that, then it's more about what kind of driver you are.

I'll be the voice in the wilderness, I don't think that 4340 shafts are all that much better than OEM, I'd call the ROI pretty low. Now if you've found someone making them from 300M, that's a different thing altogether. 300M would be my only choice to change out stock shafts.
 
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This is why I'm torn. I spent years building/wheeling CJs. The Dana 30 front end was a huge weak spot. (so were the two-piece rear axles!). So, you just always had to be careful - no full-lock (or close) turns with any load, no shock loading (bouncing, high RPM efforts, etc), no backing up any obstacle, no... etc. Punchline: I ended up being sorta "gentle" on drivetrains.

The flip side: Is this where I want to start cutting corners?
 

ntsqd

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The Mini-Truck 8" front axle is nothing like a D30. In some ways it's stronger than a D44 (axle spline size at the diff comes to mind). I just don't see the ROI for my truck, and I think that I beat on it harder than you're going to use yours.

I wouldn't look at it as "cutting corners"; I'd look at it as "do I really need the added strength or is the money better spent on something else?" I'm clear over here on the Lower Left Coast, so it's hard for me to judge, but I don't think that you do need them.

Worst case: you revisit this decision after you've had a failure.
 
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let me put this in perspective.
Wheeling is my vacation/fun time.
that said i don't want to be working or waiting on your junk because you got cheap. ;)

buy rcvs and don't look back.
 
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Re-gearing and putting in lockers is a big expense as it is. It doesn't mean you HAVE to upgrade birfs now. You won't have to undo any of that to upgrade your birfs later.

I have to reel myself in at times. If something breaks, I upgrade. I have been worried about my stock rear axles..........since about 2012. I'm now going to 37's so I'm a bit concerned again. I'll take it on local trails and hit them hard to see if I NEED to upgrade. If I start breaking things on 37's I didn't on 35's, I'm going back to 35's.
 

ntsqd

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Working on a rig out on the trail sucks. I know that others have failed OE Birf's and axles shafts, but I've never even come close to doing that and I personally only know one person who has. He used a 400ci SBC in an FJ40 converted to Mini-truck knuckles, birf's, etc. on 35's to do it.

It comes down to how hard are you going to use the rig? If you're of the "chicks dig body damage" mentality then why don't you already have D60's under the truck? But if you're more about exploring , camping, and seeing the sights and only use 4WD to get into those areas then I just don't see the need. IME it's not a justifiable expense unless you just want them. But if that were the case this thread wouldn't exist.
 
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I ran 35s locked on my 4runner for a couple years with OE birfs up front pushing 43-4500lbs with v6/dual cases and running on trails well above "exploring" only times it broke was when it should have :meh:. BUT I had the tools, energy and experience to pull the broken pieces in 30min or so. In that time I popped 2 short side birfs.

It got OG Longfields and has been solid ever since.

So 33s running "moderate" trails... upgraded axle shafts are probably not needed. But Just like winch, sliders etc. best to have in place in the time of need. RCVs if you do go forward with it.
 

ntsqd

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Post above caused a thought. If the OE birf's and axle shafts are toast and need to be replaced anyway then going RCV makes sense to me. You probably won't ever really stress them in an exploring rig, but since you're going to have to spend some money anyway they offer a nice "insurance package."
 

pappy

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Post above caused a thought. If the OE birf's and axle shafts are toast and need to be replaced anyway then going RCV makes sense to me. You probably won't ever really stress them in an exploring rig, but since you're going to have to spend some money anyway they offer a nice "insurance package."
That is the way I look at it. I recently replaced my shafts with 30-spline Longfields. I've never had a Birfield problem, but did it for the peace of mind.
 
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RCV-Made in the USA and not owned by trail gear............yet. The piece of mind is worth it. As far as I remember(fun fact warning), RCV used to make Longfields for Bobby Long until he passed then his wife sold the company to trail gear and they now have them (Longfields)made in china by a different company. RCV pays or use to pay tribute to Bobby's memory on their Toyota SA shafts. Just buy them, you're not only getting a great product, you're getting a piece of History.


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ntsqd

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Given who owns RCV I doubt that TG will ever be able to buy them. So instead they'll just rip off their product and have it made from Chinesium like a lot of their products.

But yeah, my hesitancy about buying RCV was never about their quality. Just whether the Return On Investment is there or not.
 
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I guess I'm going to have peace of mind - RCV Toyota 30 Spline 4340 and 300M Chromoly Birfield and Axle Set with Hub Gears, "has shipped".

I did that trail math. You know, when it's 6:30, the sun's setting, temps are in the 40s and ___ just broke... how much would you pay for it then?
 
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You will never have to think about front axle failure again. Maybe some maintenance (grease) and that's it.

Did you get the hub gears too?
 

ntsqd

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I looked into RCV replacement axles for my D44 TTB a while back. Coming at it from that same "piece of mind" perspective as the stock u-joints are notoriously fragile and there is no other upgrade. The issue there was that the center CVJ had to be removed from the truck to service it. So servicing just it would tie up nearly a full day. The steering CVJ's had drilled outer shafts and could be serviced by removing part of the locking hub and accessing that grease port.

Would not surprise me if they include a similar feature in the Toyota assemblies.
 

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