should i shorten the axle?

[CHB]

i have a RN40 rear diff but the axle is too long for me to fit inside my wheel tub.. so now i'm planning to send the axle to machine shop n get it shorter by 6" each of them. the machinist told me there is no need to perform any heat treatment or harderning on the axle, they said just machine it to the length and re-spline it.
is this reasonable?

[richov8]

I have had a couple of axles shortened in a ford nine inch i had with about 300hp and a locker, they all broke no where near where they re-splined just in other places due to abuse.
How many neddies have you got?
What model is the diff? f series or t series?
Chances are that you will smash the axle to pieces before tearing off the splines.
So to answer your question it wil be good.
But the more abuse the more harm is done

[CHB]

so what you have experienced was axle break into half at other place, not on the "respline area" is it?
on my plan, it should hold 400hp from the W55 transmission and running a pair of 28" X 9" hoosier slicks.
will the shortened axle hold it?

[richov8]

Gee i am a dik, late in the day-(excuses).
Oh it is G series, it will be good but if u abuse it go some 10 year guaranteed moser engineering billet items 900-1000.

[takai]

I think the question you want to ask is will the W55 hold it?

[CHB]

hmm... for the moment, i'm only curious on the re-spline axle... hehe

[takai]

G-series respline shoudl be fine, lots of meat there to hold it.
So long as you get someone who isnt doing a dodgy and cutting the splines with their dremel or something.

[CHB]

ok thanks for the tips...