Fair enough.
So let's educate him on why 33's or bigger are a bad idea with 10 bolt axles.
Let me relate a story;
I had put 33's on my 1984 K5 blazer with a 350 and open 10 bolt axles front and rear.
The stock 3.08 ratio meant much less power off the line, less compression braking down hills off road, and less effective brakes in general.
They looked great.
They certainly rolled over bumps better than 31's.
I began to wheel more aggressively as a result.
Added a pair of lunch box lockers to the 10 bolt axles.
One evening while climbing the waterfall ramp at Hollister Hills SVRA, as I had done many times before, there came a loud "bang" from the rearend.
My buddy Owen said; "I think you broke an axle dude."
"No way, it still wants to climb and besides.." I looked at the passenger mirror and saw the most horrific sight.
My passenger axle shaft was two feet out of the housing with the wheel and brake drum still attached with the weight of the truck bending the axle into an inverted banana shape
and 75w 90 weight oil pouring out.
"Yes, I do believe you are right Owen, Thanks."
Thus began a 24 hour journey to lay hands on a replacement axleshaft.
By 3AM the next morning I had completed the removal and reassembly of my rear differential to get the bits of broken axle out of the carrier and the new axle back into the housing on a 45 degree slope with an audience of drunken 4 wheel drive enthusiasts jeering.. cheering me on.
One fellow making the ever so helpful remark; "Dud, your getting dust on your gears."
"Yea, thanks dude.. really worried about that right now."
I drove it home and immediately sourced a used 12 bolt axle from a truck that had 3.73's.
Swapped the front 10 bolt to match 3.73.
And replaced the stock 12 bolt axle shafts with upgrade shafts.
It wasn't the end of the world.
But it wasn't a pleasant experience either.
By the way; you can do things like swap a 1988 and up 10 bolt 30 spline carrier and 30 spline axles into your pre 1988 28 spline 10 bolt.
But when you do the math you quickly end up very near having Boyce of someone else just build you a 14 bolt and reweld the perches to match your m1009.
I am stuck in that train of thought right now myself.
What do I really want to do with my m1009?
Would I trust myself not to try and wheel it hard later on, on a whim even, and would I end up breaking a gov loc carrier or another axles shaft?
I do a lot of vehicle recoveries up here on the mountain too.
Having a fully locked and dependable setup is mandatory for some tasks.
On the other hand; if all I am going to do is drive up and down to town and not take John Blue road and the remains of the army core of engineers road up Little Mountain, then i can live with the 10 bolts and 31's
Anyhow, maybe you'll be just fine with the 33's on your rig.
Personally it is mostly the rear 10 bolt we are talking about.
The front 10 bolt is nearly identical in strength to a Dana 44 which ain't too bad.
But breaking a front axle joint means you can most likely still get home under your own power.
Breaking a 28 spline 10 bolt rear axle shaft or the carrier and you are fixing it on the spot or towing it home.
The urge will come to mash the gas in the mud, or over those rocks, or off that bump.
Just remember what you have there and it's limitations.
