Given you have a good quality tire how many miles/years are you getting out of your tires before you replace them from wear or foreseen blowout? I know a lot of you been trailering the same path for years and have your scenario down. Would like to hear what you've been doing successfully for your situation.

I replace mine when the the side walls start to crack wide > when i ran cheap tires that was every couple years now i have firestone e range 10 ply and they look awesome 3 years in

Depends on the tires. They normally start cracking from the sun over time. I can tell you that if you blow one with no apparent cause other than traveling down the highway.... Replace them all!! I had a 2007 tandem that I bought used in 2010 and in 2012, 3 of blew on 3 different trips going 65 down highway. (45mile trip from home)

When I bought my boat in April, I had dealer change all 6 bearing and tire and get 2 spares! Sweating on hwy sucks!!

tires have an expected life span of about 8 years at which point they should be replaced. that said the worst thing is for a tire to sit. the movement of the sidewall and rubber is what helps to move the oils thru the rubber to help it from deteriorating. the sun causes them to crack because the oils are dried out on the surface and the tire is sitting so it does not get replaced. covering them or keeping them inside helps alot but they still have a limited life no matter what you do.

It depends.

Outdoor storage getting UV damage and sitting on grass or turf kills tires much quicker than them sitting inside on concrete or similar.

It's been stated, that the average tire is designed with a life of 6-7 years before the rubber has lost moisture and is not considered sound.
Some good info here:
http://www.tirerack.com/tires/tirete...jsp?techid=138

Another think that kills tires is heat, as in when towing and heating them up. Even if you have a perfectly aligned trailer that is not scrubbing or wearing the life out of the tires; temperature will still reduce their life based on low pressures, or brakes/bearings that heat up the hub/wheel--then tire assembly.

My experience.
My Myco came with Goodyears LT truck tires, and they lasted from 2004 manufacture & install until 2013 replacement without one single issue, They spent 1/2 their life outdoors, and 1/2 indoors. This is the best I could have hoped and/or asked for. I didn't push it and replaced them all last year.

I don't thing there is a set answer or best practice. Keep an eye on them. Keep them maintained,
That said, I definitely would not go past 10 years.

IF you have a tire failure, and it takes out a fender, and then some gel/glass/paint off the side of your boat, that's going to suck. IF it takes out a brake line, well then that's REALLY going to suck.

IF you find yourself asking this question...
...it's probably time to replace.
Sell the "good" yet replaced tires on Craigslist, but preface their age and previous use.

radial tires,,every 5 yrs or until you see cracks..me personally will never put a radial on a trailer..i have had my bias ply tires on my boat trailer since 1997 and i think im gonna replace them in the spring..lol

+1, I also have Good Year Workhorses on my myco from 1997 and they still look mint!!! Iam replacing them this year just to be safe. The work horse tires are impossible to find now since they are discountinued. Talked to Dan at myco and told me all the new myco's are fitted with Firestone Transforce tires. Another light truck tire. Iam sticking with the lite truck tires over radials due to the many years of luck i have had over the years.

i store indoors all year and I replace mine every 6 - 8 years depending how the tread and sidewalls look.

My tire dealer says trailer tires whether radial or bias have a 7 year life expectancy. That said, we all know there are a ton of variables. My rule since I've had blowouts is, look at the date code on the side of the tire, if it's 7 years it's gone.

I did not realize you could run truck tires on a trailer I thought truck tires belts would break from the scrubbing. So what's the difference between a trailer and a truck tire?