Axle shaft upgrades/alloys

[Rod Knee]

Looking ahead to doing some upgrades. I figure on upgrading drivetrain components before doing much with adding bigger tires. My thought was to upgrade my Dana 30 front and Chrys 8.25 27 spline to 30 and 29 spline, respectively with Superior shafts. But I see they are the chrome/moly rather than the manganese alloy that is must suited for semi/floating XJ axles.

So I have a couple questions:

1. Can anyone direct me to the kind of modest upgrades I'm talking about (I just want to do bolt on and don't plan on tires any bigger than 31's or 32's) in the manganese alloy. and 2. in the absence of the manganese alloy option, would you feel better about trailing with the OEM or the Manganese alloy shafts?

 

[mjma]

stock shafts should be fine for 31s or 32s. If you're not going any bigger, then you should be fine as is. Alloys are always great up front. They will help the D30 a bunch. If you want to upgrade the rear, either fine a D44 (hard to find) or grab a 29 spline 8.25 from the junk yard. I can't see needing alloys for 32s.

 

[uncc civilengineer]

I have no idea about what you're talking about w/ Manganese alloy....

but... running 31's or 32's, stock 27 sp. d30 shafts will be more than adequate. Alloy 27sp. shafts should never break. Upgrading to the 30sp shafts limits your locker options significantly and IMO seems to not be needed for what you're planning.

Upgrading to 29sp 8.25 shafts will require a 29 spline carrier.

 

[Dirk Pitt]

I'm guessing you're talking about 1541 when you refer to Manganese alloy.

If so, you don't need to worry about 4340 in the front 30, it is more than fine.

You can get either 1541 or 4340 shafts for the rear IIRC. Pick what you want.

 

[Rod Knee]

Yes, I mean 1541 (which I understood had some Mn added to the steel) vs 4340 Chrome/moly. And I am planning either a locker/LSD combo or two lockers, so the axles wuld have to support them.

Thanks for responding.

 

[mjma]

locking both, with only 32s, I would alloy the front and forget about the rear.

If you wanted to be safe, grab a whole new 29 spline 8.25 fromt eh junk yard (depending on your area, probably 100-200 bux) and you'll be fine. Alloys in a rear axle with 32s is kinda overkill. Although alloys in a D30, especially locked, with any tire size is never a bad idea.

 

[uncc civilengineer]

locking both, with only 32s, I would alloy the front and forget about the rear.

If you wanted to be safe, grab a whole new 29 spline 8.25 fromt eh junk yard (depending on your area, probably 100-200 bux) and you'll be fine. Alloys in a rear axle with 32s is kinda overkill. Although alloys in a D30, especially locked, with any tire size is never a bad idea.

I think that's totally backwards...... the 27 sp D30 locked on 32's will strong enough (assuming you have the 297 shafts). Now a 27sp 8.25 is about the same size as the D35...... So that's what I would change....

 

[Rod Knee]

The 8.25 rear will be modified to 29 spline, that much is given. My main question remains which alloy to use if any considering the semi floating XJ axles, taking into accout modest tire size increase and installation of the traction devices. The 1541 alloy seems scarce in these shafts.

 

[mjma]

I think that's totally backwards...... the 27 sp D30 locked on 32's will strong enough (assuming you have the 297 shafts). Now a 27sp 8.25 is about the same size as the D35...... So that's what I would change....

I partially disagree. I think you're not understanding my line of thought.

Yes, the stock shafts will be alright most of the time with 32s locked. BUT, front axle shafts are a lot more likely to break than rears, since they have Ujoints and all that jazz. It's not so much the 27 spline part that makes them weak, it's the fact that they go at angles, unlike the rear axle shafts.

the 27 spline 8.25 is still much stronger than a D35. The housing is solid, unlike the D35, and the ring gear is bigger. If I was going to upgrade the rear in this situation, I would just go up to the higher spline count, since it will cost a lot less than alloy shafts. I've never heard of people breaking 8.25 shafts, 27 or 29 spline.

 

[BlackJax]

I've heard of plenty of people breaking stock 8.25 27 spline shafts. I've only heard of two people breaking 29 spline 8 1/4 shafts (one was an alloy shaft and it was defective).

 

[Starscream]

I've never heard of people breaking 8.25 shafts, 27 or 29 spline.

x2. I'm running an open 27 spline 8.25 with 32x11.5 Bighorns and don't see them breaking any time soon - but you never know. Once I lock it I'll carry a spare 27 spline shaft (you only need one since the 8.25 is symmetric, at least where shafts are concerned) and just slap that in. If I break 2x, I'll go 29 spline alloys.

 

[Rod Knee]

x2. I'm running an open 27 spline 8.25 with 32x11.5 Bighorns and don't see them breaking any time soon - but you never know. Once I lock it I'll carry a spare 27 spline shaft (you only need one since the 8.25 is symmetric, at least where shafts are concerned) and just slap that in. If I break 2x, I'll go 29 spline alloys.

I figure on just going 29 spline switch over when I put the locker in. I don't think any locker is going to work with any spline number...pretty sure of that even being the greenhorn tha I am.

 

[uncc civilengineer]

x2. I'm running an open 27 spline 8.25 with 32x11.5 Bighorns and don't see them breaking any time soon - but you never know. Once I lock it I'll carry a spare 27 spline shaft (you only need one since the 8.25 is symmetric, at least where shafts are concerned) and just slap that in. If I break 2x, I'll go 29 spline alloys.

After you install a locker I think you'll change your thoughts about just carrying a spare shaft.... it's not very fun removing the c-clip w/ a locker installed.. If you regear to a deeper gear then it gets a whole lot more difficult. Before I locked a 27sp 8.25 I would spend a little coin on an upgrade (29 sp or 8.8 or 44 or whatever floats your boat)...

Also before I would upgrade front 30 shafts, I would carry a spare STOCK front assembly (shafts, unit bearings, etc <-- ready to bolt in) and wait til it actually breaks. I've yet (knock on wood) to break my 30 locked w/ 297 shafts (caps welded) and it gets wheeled regurarly and not easily...

 

[cal]

If I recall correctly, there are several companies making 1541 29 spline shafts. People are just starting to phase it out to 4130 as it seems to work pretty well.

Call Alloy USA and ask them about it.

If you wanna stay on 31/32's, dont effin bother. I ran a 29 spline 8.25 with a 27 spline d30, stock shafts in both (760's, welded front spiders) with 4.56 gears, no-slip lockers and 32's and *BEAT THE SNOT OUT OF IT* without ever having a problem. I carried spare front shafts and one rear, never needed them.

Now I run 30 spline inner and outer 4340's up front and 4130 shafts in the rear (30/44) with 35's and just carry a front stub, with 35's and arb's.

 

[dgrigorenko]

x2 on the Alloy USA as a manufacteror... they have an awesome warranty. oh and by the way i had a chromoly front and broke it yesterday on 35's locked. broke the ujoint which then jammed things up and broke one of the hoops on the outer stub...

 

[ZachMan]

Alloy USA 29 spline shafts $150 shipped a pair.

www.dc4wd.com

 

[dgrigorenko]

pm'ed ya

 

[killer98xjsport]

I put yukon 4340 30 spline alloys in my dana 30. First time out with the front locked broke a yukon stub shaft. But i got carried away with the gas.:doh:

 

[cal]

I put yukon 4340 30 spline alloys in my dana 30. First time out with the front locked broke a yukon stub shaft. But i got carried away with the gas.:doh:

.. That, and you bought Yukon

 

[killer98xjsport]

Ya but randys takes care of you. Had a replacement the next day.