When Should You Replace Overland Rig Tires?

[Lifestyle Overland]

We've had lots of discussion on what type and brand of tires are best, but a question I'm going to need answered soon is: When should I replace my current set?

I replaced my factory Dunlop "AT's" after 600 miles when I cut a side wall on a minor trail. BFG KO's came to the rescue and have performed exceptionally well with ZERO flats. (And that's saying something in southeast New Mexico.) I have always aired down on trails and keep my speeds low. I have always aired back up before highway travel.
I now have 36,600 miles on the rig and while the tread life if still there, I'm wondering if the tire's integrity is still safe. I'm missing quite a few pieces of lugs, torn off during our trail rides (side note: it seems as if this is more than most folks have experienced with KOs). There are also several minor sidewall nicks on every tire. So while these tires are projected to run 50,000 miles, what percentage deduction should an overlander (who uses the rig as a daily driver and family hauler) apply to this number?

I actually posed this question to a BFG engineer at Expo West, and got the legal response as expected. He did explain that you can tell when a tire is damaged internally when you hear and audible "thump" from the tire when traveling at speed. Admittedly though, this could happen right before a blow out...

So, fellow Overlanders... what are your thoughts on this? I'm currently at 72% of the projected tread life. The tires look a little rough, but the tread is still great. No audible issues thus far. And no balance issues. Should I replace them? If not, how much longer should I go?

@WUzombies I'm tagging you since you have the most experience with failed tires.

 

[Overland-Indiana]

I used to run BFG AT tires, loved them!! Only issue I ever had was when i bought a used set once, the tread was great but the tread started to peel away from the belt. Come to find out the date code put them at 10+ years old so the rubber was dried out, honestly if the tread is still good i'd run a bit longer, so long as there is no cracking between tread lugs or in side walls from where it flexes when aired down. But, the is just my opinion, and you know, just like A-holes, everyone has one.

 

[benmmc]

Yeah I'd agree with @jordanbrooks that if the tires aren't old and the tread is good, you should be good. The only things I'd worry about are the sidewall nicks. If they are pretty deep, it could be worrisome (obviously weakening the sidewall). My last set of BFG ATs went about 65k, and the tread was finally worn down under 5/32. That was about 4 years of use for me, and mine had a several chunks missing as well. Never had a flat. I had a couple sidewall nicks, but they were more like scratches that just kinda scraped up the surface. Even with that little tread, I never got stuck offroad with them, but my offroad was mostly riding on hunting land trails on the weekends at the time.

 

[SGLTRK]

I'm with the others who have replied. I'd stay with them for awhile yet. As stated above the biggest worry would be the side walls. I would check them carefully and if the nicks/cuts expose cord material I would replace the tire. If no cord is showing I would call it good.

 

[Mike G]

I have over 55k miles on my Yokohama A/T-S and they are due for replacement. Always checked the air pressure and rotated the tires every 5k miles.

 

[Lifestyle Overland]

I also forgot to mention that I'll be towing a trailer this season. Estimated weight fully loaded is around 1800-2000lbs.

 

[ShawnR]

I guess I'm a little more on the cautious side. Must be the volunteer firefighter/EMT in me. The depth of the sidewall nicks would concern me the most. But then, I run Duratracs, load range E. And though great tires, they are known to have thinner sidewalls. My wife and daughter are the most precious cargo I could ever carry. Me personally, if I have any safety concerns, I'll spend the money and replace them. If it were just me though, I'd probably drive on them a lot longer.

 

[WUzombies]

TL;DR: don't cheap out, keep your tires young, keep them aired properly and loaded properly.

Generally every single manufacture has had a products failure at some point. You often won't hear about it, there are often no public recalls and it is sometimes due to the civil suits being settled and sealed before trial. That opening scene in Fight Club is fairly real, except he doesn't mention damage to the brand name in the cost of a recall. My lights stay on due to conducting investigations into significant collisions. For me it started in a near decade of active law enforcement, being my department's lead fatality collision investigator/collision reconstructionist, teaching classes in the subject and now working in the civilian world in the same field. Ironically the civilian version of this job is more narrow focused than it was in a criminal investigation. There are "tire guys" who are tesifying experts for litigation on nothing but tire failures (and they make good money with a lot of cases), I'm not a specific "tire guy", but I can cover some generalized ground on the subject from my own investigations, training, personal and professional experience. Now bear with me for a moment...what I'm posting here is for your own personal use and purposes, it is not to be considered expert testimony, scientific and/or peer reviewed testing results or anything other than what is presented: a basic generalized overview of some reasons a tire may not function as manufactured or intended and is not stated to or imply any brand or model of tire is more or less likely to fail. Any stated professional or personal experience is not my curriculum vitae and is a basic generalization of my experience to this point.

Sorry, but thus is the world we live in.

A rule of thumb is that the higher quality tire in a manufacture's lineup, the higher quality tire you will have. Sounds stupid when you say it out loud, but of all the things to cheap out on, tires isn't one of them. You don't have to spend $1,000 a tire, but you might want to evaluate the tire cost beyond the feeling of a "good deal" the moment of purchase.

Besides the obvious tread and sidewall damage, tire age seems to matter, and seems to be especially true in the southwest where higher temperture extremes and UV exposure could be common. There is a reason why a major manufacture test track is in west Texas, besides cheap land, it gets hot.

Age rule of thumb is five years from manufacture (not date of purchase). Check the DOT manufacturing stamps on the tires to know the week and year of manufacture. Even if the tread depth is good, old tires don't go on my rig.

Think about 10%. If you overload a tire by 10% you can increase the heat cycles the tire will experience. If you run under inflated by 10% then you'll get the same. Higher heat cycles means more wear, there is a reason why the tire's ability to survive heat cycles during use is one of the listed tire model characteristics. Know what your tire's load rating is, what your rig weighs and what your load out weighs. If you don't know find a local farm co-op or go to the city dump (where you'll often find the cost based on weight, so you get your vehicle weighed).

If you're in your car tooling down the highway at 50mph a catastrophic failure may only be annoying and result in some body damage from the tire. Driving on the interstate at speed in your higher CG overlanding rig and you can quickly find yourself cartwheeling through the median ejecting all the stuff and people not strapped down.

Catastrophic failure may not be a sidewall or casing failure (blow out, zipper failure, whatever you want to call it, there are various failures of a similar theme people generally refer to as a "blow out"). It can be a delamination where the casing retains some pressure but you loose the tread and much of your tractional forces. Those can often result in a yaw towards the failed tire, a yaw away from the steering input then the yaw out to trip point, which again finds your rig cartwheeling through the median.

If you search YouTube you can find some exceptional testing footage, including one famous test with a certain vehicle that has resulted in a significant amount of litigation experiencing a delam and rolling inspite of the professional driver and attached outriggers. That video was a manufacture's test, was leaked and, as I understand it, has resulted in more litigation from both sides, but it still pops up on the internets some how...

Overall points: don't cheap out, keep your tires young, keep them aired properly and loaded properly.

This is a good resource to start your personal education on the subject: http://www.tirerack.com/tires/tiretech/tiretech.jsp

That is the very top of the iceberg, followed by many studies, tests, cases SAE papers and other publications and findings that drive each of the official opinions and NHTSA guidelines.

 

[Byron Eby]

Yeah, what he said ^^^

 

[Lifestyle Overland]

@WUzombies and everyone else, thanks for your input. I'm leaning more and more towards replacing the tires before our Death Valley trip with the Turtleback. They really have been through the wringer, and while I can't confirm any of the side wall nicks are significant I don't think I'm going to take any chances.

(Now, to decide on tires... stay with 275/70's or move on up to 285/70's? Going with KO2's either way.)

 

[Jacob_S]

I like to run my tires to half the tread depth as new. The siping is usually gone by then and you can actually sell them for a decent amount of money still. Sold some 35s that were 8 years old an half tread for more than half of what I paid for them.

 

[MOAK]

I've run nothing but BFG for over 25 years. and 3 vehicles. After hundreds of thousands of miles and plenty of 2 track, I experienced only a single failure, a too long valve stem was pinched by a rock and ripped out, which was not a tire failure. I abide by a few rules,, 34-36psi on the road, 18-psi on trail, always air down, always air up. I rotate all five tires, and after 4 years, (usually 40 to 45k miles) I'm replacing them with new. I was amazed that my last set of 315s sold for over 500 bucks, and the guy that bought them was elated.. My trailer tires, you may ask? The trailer scales out at between 7 and 800 lbs depending upon load and I have been running those tires, (picked them up used) at 22psi for over 4 years. After our trip this spring I'll be looking for another set to rotate in with the 285's on my 450.. (which means I'll be rotating 7 tires) When it's time for new tires I'll keep the two best tires on the trailer. My father in law thinks I'm a weirdo spendthrift about tires, my wife learned after a few years how nice it is to have never had a flat since we've been together. (30 years) Andrew St Pierre White and Paul Marsh have a great discussion on tires and wheels that confirmed my ideology about tires. If one isn't familiar with these names, check out the 4Xoverland.com website..

 

[Lifestyle Overland]

@oldfooladventures Thanks for the input. That further confirms my decision to replace the KO's with a fresh rubber at 40,000. I have an appointment tonight at Discount Tire to make this happen.

 

[MA_Trooper]

You will be very happy with the KO2s. I have them on my rig. About a year old now. I love them. Going from the KO, you will think you have street tires, they are so quiet.

 

[Lifestyle Overland]

@cjones That's great news... how are they on gravel? The KO's loved to eat them up and shoot them at anything nearby.

 

[MA_Trooper]

@cjones That's great news... how are they on gravel? The KO's loved to eat them up and shoot them at anything nearby.

They still shoot gravel up into the wheel well. Not nearly as much, though. I still haven't lost any lug chunks. The new material is quite strong. I have cactus and mesquite thorns sticking out of the sidewall and still no leaks.

 

[Lifestyle Overland]

I'm missing a LOT of lugs on the KOs. Part of the reason I'm going to go ahead and upgrade.

 

[Kelly]

This tire was brand new (when I put it on my spare tire carrier 12 years ago). When I needed it, last week, it would still hold 50psi. This is a photo of it after 1 mile on a dirt road...



NOTE TO SELF: Rubber doesn't like sun ;-)

 

[WUzombies]

This tire was brand new (when I put it on my spare tire carrier 12 years ago). When I needed it, last week, it would still hold 50psi. This is a photo of it after 1 mile on a dirt road...

View attachment 7144

NOTE TO SELF: Rubber doesn't like sun ;-)

I'm glad you're ok!

That appears that it could possibly be a delamination, aka a tread separation (stated without a detailed tire examination). If you had been on pavement and at normal speeds there is a good chance that the loss of fractional forces and lateral stability could have resulted in a rolling event. In other words you would have cartwheeled down the median ejecting all the shit not bolted down to your rig.

Tire's don't stay on any of my vehicles in any capacity past 5 years of the date of manufacture, not the date of purchase but manufacture (regardless of how much tread life is left). Look at the DOT manufacturing stamp on the sidewall,the first two numbers is the week, the second two numbers is the year. So 4111 would mean the 41st week of 2011 was the date of manufacture and that would mean that I would be replacing that tire very soon.

 

[offroadohio]

I have worked in the tire industry since 2004 and have various training pertaining to Michelin and Goodyear

As a guy with several years of experience in the tire industry in passenger vehicle and commercial truck as well as a retread facility there are plenty of tires that will go well beyond the 5 year mark and tread life expectancy doesn't mean crap.

Michelin tires are "landfill" safe this mean the are biodegradable. I.e. they dry rot faster. Bfg is part of Michelin but they are not designed landfill safe.
As mentioned good years have thinner sidewall usually and even with Kevlar are less puncture resistant than other, but I have noticed good years don't seem to show as much age as others.

There are no age restrictions placed on tires by the federal government because there is no data showing that a 6 year old tire is more likely to fail than a 2 year old tire.

In my experience age very very seldom ever a factor in failure. Sidewall impact, (hitting curbs) and under inflation are the 2 biggest.


But with that said, the 5 year rule of thumb mentioned in a previous post is a good base.
And Ultimately if you think the tire needs replaced it probably does.


Here is a tire I just removed from service.

It's a semi trailer tire and still holding 105psi. Came in on a loaded trailer.