I'm not sure on the gain of alloys over stock for the 27 spline shafts. Yes, you will gain some strength, but (for me) not enough to be comfortable with the bigger tires. With that said though, I wheeled my 33's on stock shafts for 2 years with no problems at all...but I think I was an exception to the rule, and also light on the gas.
I then came across a deal for a S35, complete axle with a Detroit, so I grabbed that. I wheeled with the 33's another year, and have been on 35's for about a year as well- no problems to speak of as of yet. The added strength of the bigger shafts has made me more comfortable on the trails, and I've gotten on to the gas pretty hard more than once to get over an obstacle. So far, everything has been great.
REDLYNER Racing #4550
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