Not trying to repeat myself.
recently had a hub explode on me

for prevention maintenance
what is best to do and how often?

should i take free wheel off/ cassette. once a year and lube everything inside?

seems quite a tedious and time consuming?
but would this prevent from system breaking and prolonged the life of it forever?

Wow, what do you mean by explode? Hubs, if traditional cup and cone should be serviced periodically depending on mileage/riding conditions, etc. Many how to do its on the internet and in bicycle books. I like Lennard Zinns book myself.

some freehubs are not made to be serviced and some are virtually impossible to find replacements once they go. some are really not very durable at all and that sucks.

I'll also ask what do you mean "explode"? Actually fracture into pieces, bearing failure or just the freewheeling mechanism either seize or freewheel both ways?

Anyway, yes, periodic overhauls and relubing should be done for cup-and-cone hubs and periodic relubing of the freehub body is also recommended. Will they last forever if you do it? Of course not but they will last a lot longer than if you don't. Tedious and time consuming I suppose if you aren't willing to put a couple of hours a year into maintaining your bike.

I overhaul my shimano hubs at about 2500 miles and the freehub body every 500 miles. I rarely need to replace balls.

I don't do it nearly as often but I overhaul (clean, new balls, grease, adjust the bearing clearances and oil the freehub body) my Shimano and Campy hubs at 7500 - 8500 mile intervals or about every two years on the two bikes I ride the most. Thus far I have 50,000+ miles on a Campy Chorus front hub, 40,000+ miles on a set of Shimano WH-R560 wheels and over 72,000 miles on a FH-7700 Dura Ace freehub. All of these hubs still have the original cones and races and the original freehub bodies still work perfectly.

You used to be able to disassemble Shimano freehubs with a special tool, but that tool is very hard to find now. probably better to remove it, flush it out, and dribble some new oil in there. https://www.parktool.com/blog/repair...icle-section-2

https://www.steintool.com/portfolio-...eehub-flusher/

I've never overhauled a free hub. I've never had issues with one. I have had issues with freewheels on my kids bikes that were left out in the rain.

Do you wash your bike? Maybe just wiping it down would be a better choice to keep from getting water up in the freehub that won't dry out till well after the rust starts..

I find it hard to believe that someone rebuilds their free hub every two or three months. My oldest free hub is five years old and quite a few miles on it. It's never been opened. When It goes bad, I'll be happy to put a new one on it and rejoice that I didn't spend time fiddling with it instead of riding... or posting here at BF when I should be riding. <grin>