Hey folks, I was hoping I could get your input on this. Dynatrac and ORE will build me a pr44 with a 35 spline ARB and 35 spline axles. Northridge prefers the 30 spline ARB and axles. They say they 35 spline shafts taper down to 30 spline anyway, and cause inner seal issues. Now I'm in southern california and will likely go directly to dynatrac for my axles, however Northridge probably builds a lot of these things too and their experience with this issue shouldn't be discounted. Any thoughts? Thanks :beer:
Conflicting info from wayalife vendors regarding dynatrac prorock 44.
- Thread starter qwasin
- Start date
OscarMike2.0
New member
I havent heard of anyone having a inner axle seal leak due to the 35 spiline shafts. I asked dynatrac about it when they were building mine and they said a leak in the 35 spiline is just as likely to happen in a 30.
BigPrince
New member
This is a quote from Dynatrac on another site on the Internet:
"The PR center section comes in 2 designs, one for the factory locker and one for conventional lockers. If you buy one that is designed for a factory locker and decide to use an ARB, a specific ARB model (RD157) is required. It requires 35 spline shafts. Do not confuse these 35 spline shafts with what is used in a 60. The RCV shafts that are used are only the 1.5" 35 sp diameter for about the inner most 5". The balance is the same diameter as a std 30 spline. There is no appreciable increase in strength over a 30 RCV shaft. "
I wouldn't bother with 35spline.
We have had many issues with the 35 spline seals. They are not as good as the stock seals.
The axle shafts are the same diameter all the way until about the seal surface. I am in canada right now but when I get back I can get you some pics.
We are having little to no issues with 30 spline.
The outside diameter of the side gears remains the same 30 or 35 spline. But the Id of the side gears have less material for the 35 spline.
We will build you a 35 spline ran prorock but we feel for the added cost and poor Inner seals it's not a worthy upgrade.
David
The axle shafts are the same diameter all the way until about the seal surface. I am in canada right now but when I get back I can get you some pics.
We are having little to no issues with 30 spline.
The outside diameter of the side gears remains the same 30 or 35 spline. But the Id of the side gears have less material for the 35 spline.
We will build you a 35 spline ran prorock but we feel for the added cost and poor Inner seals it's not a worthy upgrade.
David
Heholua
Member
Basically it boils down to what you're comfortable with. I bought my PR44 from Northridge with the 30 spline ARB locker and RCV shafts and no problems whatsoever. As other people have said, with the 35 spline shafts the only part that is larger is the spline area. Good luck with your decision.
Yes this is a difficult and expensive decision. I wish I could justify 2x the cost for the 60 front but that is not in line with my wheeling needs. If going with 35 spline offers no strength improvements over 30 spline and can cause seal issues then it's a no brainer. But I was hoping that some of the shops who build 35 splines or folks who run 35 splines could weigh in here and sell me on that setup. I know eddie has recommended 35 spline I will see if I can find the thread.
Heholua
Member
The Rubicon PR44 housings only take the electric locker or the 35 spline ARB. The non Rubicon PR44 housing can do both 30 and 35 spline ARB locker.
Just a suggestion, if you purchase from NR 4x4 have them weld on the raised track bar bracket.
Tree Frog
Member
So pardon me being stupid (its normal for me)
Is this seal leak problem with the factory Rubicon D44 running a 35 spline axel shaft also, or just a Dynatrac PR44? Also Front or back or on both?
Reason I am asking is I just ordered and am waiting for install on an ARB air locker for the rear of my Rubicon D44. As said above the factory Rubicon will only take the ARB 157 and that will only take the 35 spline axel shafts.
Really don't know what else to do. Stupid factory e-locker is toast.
Is this seal leak problem with the factory Rubicon D44 running a 35 spline axel shaft also, or just a Dynatrac PR44? Also Front or back or on both?
Reason I am asking is I just ordered and am waiting for install on an ARB air locker for the rear of my Rubicon D44. As said above the factory Rubicon will only take the ARB 157 and that will only take the 35 spline axel shafts.
Really don't know what else to do. Stupid factory e-locker is toast.
Front only the rear doesn't have inner seals
As mentioned, the rear only has outer seals. I recently replaced my factory locker and went with an ARB. I'm happy I did but make sure you or the installer grinds the needed drain holes. I have the Nitro 35 spline shafts and they are pure beef. Still, this is a semi-float so the flange is the weakness that will likely push me into a PR60 FF soon.
I actually thought I had a bent flange on these shafts after the Rubicon, but after a closer look they were okay. I still hate the constant worry.
Ok so just some cliffs notes.
With respect to a dana 44 front axle...
30 spline side gears have more material (stronger?) than 35 spline
30 spline inner axle seals perform better than 35
30 spline and 35 spline axle shafts share the same diameter for the majority of their length
The choice seems obvioius...
Northridge, can you think of any benefit to 35 spline? Just seems like if it was this simple, everyone would be building 30 spline? I'm definitely leaning in that direction now. I just had to get over the psychological hump of "not going as big as I could". Thanks for the input, and I'm still open to more opinions.
With respect to a dana 44 front axle...
30 spline side gears have more material (stronger?) than 35 spline
30 spline inner axle seals perform better than 35
30 spline and 35 spline axle shafts share the same diameter for the majority of their length
The choice seems obvioius...
Northridge, can you think of any benefit to 35 spline? Just seems like if it was this simple, everyone would be building 30 spline? I'm definitely leaning in that direction now. I just had to get over the psychological hump of "not going as big as I could". Thanks for the input, and I'm still open to more opinions.
I'm not Northridge, but a common issue on the front is twisted splines as the shear is focused at that point. The higher spline count and shaft diameter would help with this problem area. Unfortunately, it sounds like at the cost of creating others.
Many people have then and don't know until it breaks. I have found several while pulling shafts for other reasons. From what I've seen (and I'm far from an expert) the U-joints usually fail for one of two reasons, the cap backs out or too much gas with the wheels turned sharp. I have seen shafts snap and the u-joint be happy as a clam. (I've never understood this analogy :thinking
mudmobeeler
Caught the Bug
The RCVs can twist at the splines, which according to them that is acceptable. Least thats what Ive seen and read on here. I have zero first hand experience with them.
This is correct, and total crap. I do have first hand experience with this. I had shafts with splines so twisted I was not able to use them, but by RCV's warranty rules they were not damaged enough to replace. This was however on the 27 spline shafts. Several have told me this is not an issue on 30+ splines, but they are not getting any more of my money for me to test.
mudmobeeler
Caught the Bug
It makes you wonder though. So many of the all out buggy/rock bouncer guys run them. They either don't have issues, or aren't talking about their issues with them. And they trash on their rigs. Course they are running 60s, 14 bolts, etc. not dana 30s or 44s. Lol.
You mean issues like this D60 RCV CV cage off my buddy's rig?
He also has also broken several shafts. Luckily for him, it was warranted because the completely failed.
This is just my opinion, but I think the RCV sponsor stickers keep them quiet. :crazyeyes: Truth is, I do love how smooth they are. But let's be honest, a large part of the exorbitant cost justification is the claimed "no questions asked" warranty. In practice, they will ask questions and they may not cover it. Still, If they were in the wheelhouse of the cost of a CM shaft I would consider them again.
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