Topic: 21 spline vs. 23 spline

[Volcom]

I've got an 85 PU with the 22R and a forward shift case in it.  I bought a w56 tranny and top shift case a couple of months ago and want to run dual cases.  My main question is about the spline numbers.  Is it worth the time, money, and hasle to convert these cases to 23 spline?  I don't plan on running monster V-8 power.  Since the adapters are the same price, what's the cheapest way to convert to 23 spline if I need to?  I figured this would be the place to ask and get some real world answers.

Thanks for the help,
Aaron

[derek]

the w-56 is 21 spline output.
you would only be able to convert the last case to 23 spline.
but i doubt you will kill a 21 spline input with the 4cyl.
i have not met anyone that has that is still running the 4 cyl.
met a couple people that have snapped t-case outputs though.

derek

[KYOTA]

met a couple people that have snapped t-case outputs though.

If I remember right FatA$$ has, maybe he'll post up the pics

[derek]

i have been running my 21 spline setup for 5 years now with no problems.
and i am not to easy on my junk.

derek

[Ferg]

I run a 4.3L GM V6 infront of 21 splines and a W56.

Any questions?

[Volcom [OP]]

I run a 4.3L GM V6 infront of 21 splines and a W56.

Any questions?

Nope, that's what I like to hear!  21 Spline it is 

[Marketing]

23 spline is stronger than 21, and a few 21 spline rear cases have broken the rear input.

The front 21 spline inputs really don't have a failure problem, it's the 21 spline input on the REAR CASE that fails. The front input takes the stock torque, the rear input get the torque after it's been multiplied by 2.28. So the rear input get 2.28 times the power as the front one. That's why we see failures in the rear. If you purchase gears and a dual adapter, order them both 23 spline. Ordering 21 or 23 kits costs exactly the same, you just have to do both at the same time. You can't use a 23 spline dual kit with 21 spline gears. You must match the rear gears with the dual adapter.

Again, if you are buying a dual adapter and rear gears, get the 23 spline, it's stronger and does not cost any more. No other parts are needed and you get the strength of 23 setup in the rear.

Every dual ultimate crawler we build at the shop has 23 spline gears in the rear case!

[derek]

chris is right.
if your going dual ultimate then get the 23 spline adapter and 23 spline 4.7 gears.
but if your only going dual cases then you will either have to buy a 23 spline input for the rear case or just get the 21 spline adapter and not have to mess with the rear case.

derek

[Volcom [OP]]

So, I've really got to think if I want to step up to the 4.7 gears one of these days    before making my decision on what adapter to buy.  That will make it tough.  Anybody in the same boat?  I was only planning on running dual cases and 5.29's and 37's with a stock 22R.  I don't know which way to go now 

[derek]

if your just going dual cases just get the 21 spline setup.
you can upgrade later if you are worried about it.
lots of us are running dual ultimate 21 spline setups.
just go with the 21 spline adapter and run with it.

derek

[cgbemis]

21 spline inputs are free. If you are truly "getting it" enough to break an input, it won't cost you anything. When you go to 4.7's, you can either sell off your adapter and use the money for a 23 spline unit, or just replace the coupler with a 23 spline coupler.

[my toys]

I run 23 splines front and rear with a v8. 4.7 gears in front case, 23 spline stock gears rear case.I have broke a 23 spline turbo gear in my rear case, but Marlin said it must have missed a heat treat. or something to cause it to break. Marlin made it right and I was back on the trail in no time. Went back to the same place
I broke and tried it again and it held together so it must have been a bad input from the factory...

[lowgeared]

Mine are both 21 slpine and I flog the crap out of it with no problems.     

[Brandon]

I swapped to 23 when I put in the V8 but I never had any probs with the 21 - just seemed to be the thing to do..