Makes perfect sense, thank you. Though I dare say the guys breaking the 27 spline 4340 shafts in JV are in the .01% of wheelers I was referring to as excluded from the 27 spline spline 4340 bunch is enough group.
Should I go with 27 or 30 splines for Dana 30?
- Thread starter Jeepin' Geo
- Start date
It always works until it doesn't. The problem with when it doesn't is now the 30 spline inner upgrade costs you right about double. That's a hard pill to swallow when the average cost to install a 27 spline locker and alloy shafts is not much less than what it takes to install a 30 spline locker and shafts.
Maybe kinda sorta for the LP 30, move away from that to anything else and the gearset isn't the weak link.
Wonder if anybody has figured out a seal to fit in the axle tube for the long side of a CAD 30 running 30 splines.
Revolution would know since they sell 30 spline kits for YJ and XJ. Those same axles on 27-spline with the CAD delete use Napa 11800 which theoretically could be hammered all the way down the tube since the tube is not machined for a seal. They just put RTV on the edge and hammer it to the right spot on the shaft and stop. The 30 spline option would be the same except with a larger ID for the thicker shaft. I’d bet Revolution could share what they supply in their kit for CAD axles.
They might, or they might say that it doesn't work on CAD housings because there's not enough room for a seal with the larger shaft.
It sounds simple, but the reality is that the ID of the axle tube changed at least once during production and if the first seal you buy actually fits, you got lucky. The first seal I tried was like a hotdog in a hallway.
They sell axle shaft kits specifically for the CAD axles, which come with 3 seals. I don’t see why they would sell that if it won’t work…
Do you have an old XJ axle?
My LJ has a CAD HP30 in it. It was already pulled so I don't know what year xj it came out of but the cover it had on it was date stamped for 1989.
And you bought the 3-seal axle shaft kit meant for a CAD axle from Rev?
If so, that’s odd for sure. I know the intention is to put a seal at the CAD and one at each side of the diff. Which is dumb because the purpose of the new seal at passenger diff makes it to where you don’t need a seal at the CAD, and the full length shaft isn’t machined for a seal at the CAD anyways so having a seal there makes no sense. But they still give you one.
No, mine are just 27 spline. I used my stock TJ shafts when I originally did it in 2019 and I hunted around on the internet until I found a seal that fit the axle tube at the diff. I have a seal at the CAD too but I don't expect anything out of it since the shafts aren't machined there for a seal and it doesn't receive any lubrication. Mostly it's kinda nice to guide the shaft in as I install it.
I’m wondering which seal you used then. 11800 has been perfect for me. No hotdog in hallway problem. I’m using a stock TJ passenger shaft as well. I deleted the cad seal although I can see the lineup aspect being nice.
That might have been what I ended up with. The first one I tried was a timken that I found on a site that seemed no less credible than any of the ones pitching the 11800. ECGS I think sells two different seals, one with a smaller OD which is probably the one I tried first. The hotdog analogy is probably exaggerating, but it definitely wasn't tight enough to stay in place.
Yeah, I don’t know. All I do know is the 11800 is pretty much only found at Napa unless you do some cross referencing. It has worked for me in two axle housings on one shaft. I have heard some of the older axles though don’t fit right, so maybe it’s since yours is from 89. Both of mine were 90s.
OP, if you're going to the trouble to rebuild your LP 30, as has been said, the best option is to find a HP 30. That said, your biggest issue, given you stated E Lockers, will be the availability of a 30 spline Dana 30 E Locker. I've had one on order since 11/21 and Eaton can't give an ETA. If you do decide to go 30 spline inners, you'll have to install an ARB. Those are available in a 30 spline.
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