[alien]

I'm getting new ones made - if anyone else would like to hop on board just shout out? Still working on who to use to get the best price on 4340 material.

Hoping to hit the button on it ASAP as my current axles are self-destructing.

[tanshi]

Any idea of $?

[Gwagensteve]

I wouldn’t bother with 4340 personally. EN-26, Hytuff or 300M for my money.

[alien]

Steve - interested in your thoughts on material!

Tanshi - was supposed to get a price back today but never came in.. hopefully tomorrow

[BlueSuzy]

Bundera ones are pretty good

[alien]

Wait, Bundera axles are the right size, spline count etc!?

[Gwagensteve]

No. It was a joke.

I’d always suggest using the best material you can afford. 4340 is adequate for a 26 spline front but the rear sees a lot more load. I know you’re running a relatively small tyre but the cost in axles is predominately in the labour to produce them- stepping up in material is relatively inexpensive and a broken axle is pretty inconvenient.

Do your JML axles have that dumb circlip groove to mimic the clip on a vitara stub axle?

Steve.

[alien]

haha well at 4.30am I fell for it =P

I'll see what the shops can do for material. I thought 300M was just 4340 're-badged' ?

Yes, mine have silly circlips and no the new ones won't have them on there.

[Gwagensteve]

Yes it’s a modified 4340, and importantly it’s a vacuum arc remelted product, not all 4340 is.

As far as I can see, it offers more “twist” before failure than 4340, and that’s critical. However, whether that twist can be utilised will depend on good axle design and I have seen (and bought) some very poorly designed axles that fail readily in the spline because they aren’t smoothly waisted down to less than the root of the spline diameter

A new one I saw the other day was a floater axle tapered from diff to hub end so “it breaks at the hub and is easy to remove” the person who posted in on #FBtech couldn’t understand why that was dumb because it concentrated twist into a small area.

There’s a worrying lack of science about axle design- it seems many US axle makers believe that using exotic material means their axles will be indestructible and they don’t need to engineer them to flex. In reality, the driver’s side axle on a Sierra should probably be smaller diameter or gun drilled to promote and enhance twist- they aren’t long enough to disperse enough twist along their length.

So from that point of view I’d still go 300m or Hytuff over “regular” 4340, unless you know the 4340 is vacuum arc remelted, and still insist on a high level of workmanship and design.

[Gwagensteve]

Just to be clear- 4340 is chemically (slightly) different to 300m which, amongst other things has higher silicone.

[alien]

Awesome info, thanks mate!

100% agree on the twist. I had stock rears twisted by a whole spline and it still drove great other than a big clunk taking up the slack... I'd rather twist axles than snap them!!!

I find it interesting that the one that's failed in mine is the long side though. Would have thought with more torque going through the short side that'd fail first.

[Gwagensteve]

Definitely consider EN-26 or Hytuff too.

Causes for accelerated spline/drive flange wear on the passenger side might be due to a bent housing or (more likely from what I’ve seen of JML axles) an out of square axle. Joe seems to have had some problems with lathe chuck alignment from the axles I’ve seen.

[alien]

Yeah, I get some weird drag noise on the rear rhs - scraping sound of the brass bushing i think, because the axle is warped or something. Mostly under engine braking and in reverse.

I was at a Subaru drive day today and Dean Herridge was there so have asked him for any contacts for manufacture as well.. be interesting to see who his engineers recommend!