28-spline hardened vs. 31-spline axles

[myrsvt]

Will be putting on Nitto 315 555r's soon and hitting the track some (not alot).

Question is, I now have all stock rear so, how much strength would I gain with just upgrading to 28-spline hardened axles like this:

Moser 28 Spline Mustang Axles for 8.8in Rear w/ Studs (99-04 GT, 01 Bullitt, & Mach 1) A882853 - Free Shipping!

and using stock carrier vs. going all the way with 31-spline carrier and axles.

What is the weak link? Axles or carrier?

 

[cinch1985]

well i twisted a set of 28 spline harden ones

 

[myrsvt]

What kind of power we talkin that twisted yours? Slicks?

Just seems strange that 3 more splines can make a huge difference?
Don't know tho:shrug:

 

[myrsvt]

Still doing research trying to figure this out.

Most people twist and break axles, correct?

Or, do they sometimes (strip) or fail at the splines?

If the axles themselves are the weak link, why do people go to the added work and expense of changing the carrier to 31-spline??

Need your guys expertise!

 

[98 N/A 4V]

they are only 3 more splines the diameter is very noticeable. I would get the 31's. I have 31 mosers and dumpled the clutch probably over 400 times on them.

 

[cinch1985]

I was on dr's and was makin 430

 

[PSUCOBRA96]

its not just the numerical number of splines, the axle is much thicker which is were you get your strength from.

 

[myrsvt]

The diameter of the axle (regardless of number of splines) is going to be
limited by the diameter of the bearing it must slide through.

Factory 28-spline axles are tapered I know but the aftermarket 28s like Moser are advertised as non-tapered so you wouldn't gain any thickness going to a 31spline.

Correct me if i'm wrong but I still see no need for the added work and expense of the carrier upgrade for an occasional weekend warrior like me??

 

[epracmetcon]

Do yourself a favor and get the 31 splines. You can pick up a used rebuilt carrier out of an explorer/cobra for under $100.00.

 

[cwaysvt]

I think i'm with him on this. If the diameter of the aftermarket 28 spline axle is the same as the diameter of the 31 spline axles, whats to lose by staying with the 28's in an aftermarket, non-tapered form and the stock carrier? Unless anyone has a case where the 28 splines have been stripped...

 

[Tyler72]

Are you guys serious? There is a huge difference in diameter between 28 & 31 spline axles. Also, the cross pin in a 31 spline carrier is 3/4" compared to the 28 spline carrier's 5/8" cross pin. Huge difference in strength in both aspects.

 

[ESVEETEE]

For 31 splines to fit in the same diameter as 28 splines, the valleys are probably more shallow and narrow = more material and stronger.

 

[PSUCOBRA96]

31 splines are bigger than the 28, which is why you have to change the carrier, the one will not fit the other.

 

[myrsvt]

Ok. That makes sense that 28s are smaller on the splined end.

What threw me off is the aftermarket 28s are advertised as being (non-tapered) and 28s and 31s
have to be the same size on the wheel side because the sit inside the same bearing.

 

[mikeracing]

i know this is an old thread but in theory i am in aggreance with the 28 spline aftermarket axles being non tapered being nearly as strong as the 31

and i understand the center pin being different diamaeter but how many pins have broken?

 

[Tyler72]

28 spline shafts have a major diameter of 1.208" at the splines.

31 spline shafts have a major diameter of 1.333" at the splines.

I know that doesn't seem like much, but its an 1/8th" increase in diameter & a .393" increase in circumference. Basically its a 10% increase in size, but its even more than that in strength. I picked up a used explorer carrier for $25 & tossed in some new 03-04 cobra carbon clutches (which you would probably want to do even if you kept the 28 spline carrier) so I've got less than $150 in upgrading to a 31 spline carrier. Well worth it for a brand new posi unit & the piece of mind.