has anyone ever broke a 1-3/8 inch input shaft on a 5 speed

J

jaybuller

USCG MK
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Mar 27, 2009
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I'm trying to figure out if I need a billet shaft or a regular 1-3/8 . For sled pull under 650 HP. And boosted 4x4 launch.
 
Do you need a billet 1-3/8" shaft?
Under 650hp = no
4X4 boosted launch = yes
 
My trucks have always been auto...once you break a few manny trannys you'll figure it out.
 
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Muddin_dude06 said:
Aren't all the clutch supplier's 1-3/8" input shafts for NV4500's billet?
Click to expand...

Billet is very general terminology...stock shafts are billet for that matter.

From Valair you can get an import shaft or a USA made shaft for around $600 or you can get the good Haisley shaft for around $850. I prefer the best.
 
Our import shafts are forged, as are most out there for sale. Our USA shafts are custom made for us out of 4340 Billet, and are USA made. We usually dont see the import shafts break unitl over 700 hp, but then again it would depend on what your doing with it like Lee said.
 
What about a truck that just towes alot, pullin truck,cattle, ect, with a couple of box's? is the big shaft needed ??
 
I've seen bone stock trucks tear centers out of clutches and break input shafts just as quick as a lightly tuned truck. Sleddy got a good idea!
 
Got one sitting on my wall of shame as well was shifting from 2-3 at full throttle when it let go.
 
1 3/8 billet is what i broke as well as shearing numerous countershaft gears to pieces over the years.
 
Wow, hey Creed what kind of power were you making to be doing that? is it hapenning when your shifting or when your rollin into it hard? im tryin not to bust my tranny up. tryin to figure out how i need to drive it, and when not to pour the coals to it...
 
I was full throttle shifting at the time the input broke as for the countershaft gears I was having problems with I tried just about anything from cryo treatment to new mainshaft even thought the one in it was the new updated one and didnt have hardly any miles on it etc and still broke them all the time finally I gave up and swapped in one of Jeff Garmons Race version 47re mvb and no more issues after that the truck was around 700hp or so made 755 last time it was on the dyno.
 
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I got the 1 3/8 input from sbc. Never had any problem with it. I have twisted the end of the counter shaft off. Although it does sound pretty when you snap the stock input at 1400 rpm with a load of hay behind you like my buddy did. He had all kinds of problems after that with the tranny.
 
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