Interesting crack in semi trailer tire sidewall

[Sj08]

This is not my vehicle, I am helping part time when the regular driver needs to take off 2 days per week for about a month.

I showed it to the owner, and he said they have been watching it all summer, and if it gets bigger, might have to change it.

This is on a side dump, the pit is 110 miles away, and load up max gross, sometimes 500-1000 pounds over, and drive back. 2 loads each day.

I am surprised that this made it through the summer heat.

Just thought I would share what some folks are comfortable sending out there. I was a little nervous about it, but it's on the passenger side, and very rural low traffic area, so if it would let go, shouldn't affect other drivers.

 

[Pew]

Looks good from my house!

 

[KGMtech]

China. Must have skipped the UV resistant rubber formulation?

 

[Danno]

If there is any kind of a CMV roadside inspection in your state, it would be grounded, plates pulled until repaired.

 

[wwillson]

@CapriRacer what causes sidewall cracks like this?

 

[Sj08]

China. Must have skipped the UV resistant rubber formulation?

Probably right. They should rotate it to the inside so it is protected from the sun.

 

[Sj08]

If there is any kind of a CMV roadside inspection in your state, it would be grounded, plates pulled until repaired.

They do, but typically on the interstate or busy 4 lane highway. In the rural area's, might see a county sheriff running around once in a while.

 

[walterjay]

I think it should be pulled off the road

 

[Sj08]

I think it should be pulled off the road

I agree, I might refuse to drive it if it isn't replaced when I am supposed to work again in 2 weeks.
Amazing that it has looked like that for the last 5 months.

 

[hemitom]

Ya sounds like a really concerned owner ! really why doesn't he tell you the truth that he has no intention of changing it until it blows and has no concern of his drivers safety or that of others on the road .

 

[spasm3]

That just looks old. Whats the date code ?

 

[Mainia]

I myself would refuse to drive the truck out of safety for other people. That lets lose at 9 clock to 3 o'clock next to a passenger car or pedestrian, it's not going to be pretty.

 

[walterjay]

We all know that at some point that tire is going to blow

 

[Sj08]

Ya sounds like a really concerned owner ! really why doesn't he tell you the truth that he has no intention of changing it until it blows and has no concern of his drivers safety or that of others on the road .

I don't know him well enough to say if he doesn't care, or if he truly thinks it is fine like that. He seems nice, and has 3 long term employees. I was approached when at Napa, if I could help a couple days a week while his driver was going to be gone.
We are supposed to have a winter storm this week, so hopefully the gravel season will be done.

 

[Sj08]

That just looks old. Whats the date code ?

I couldn't find one, guessing it's on the inside.

 

[Owen Lucas]

That just looks old. Whats the date code ?

Probably 1962?

 

[Sj08]

I myself would refuse to drive the truck out of safety for other people. That lets lose at 9 clock to 3 o'clock next to a passenger car or pedestrian, it's not going to be pretty.

I agree. The only good thing is it's on the passenger side, and a very rural light traffic area, might scare some cows in the pasture though.

 

[50yr Street Mech]

That tire is junk. When I was driving my work truck, I had to fill out a daily vehicle inspection sheet. Tires were one the the things to check. I had the right not to drive it if their was a bad tire.

 

[Chris142]

Ya sounds like a really concerned owner ! really why doesn't he tell you the truth that he has no intention of changing it until it blows and has no concern of his drivers safety or that of others on the road .

Ya that's a d.o.t. red tag for sure.

 

[CapriRacer]

@CapriRacer what causes sidewall cracks like this?

That looks like a junction between 2 different rubber compounds. Notice the weather cracking is much more severe below the opening than above it. The question for me is why are there 2 different rubber compounds there. I know of no reason for this.

This tire appears to me to have been underinflated/ overloaded. It also appears old.

There are 2 causes. The first is simply the junction coming apart, may be due to age.

The second is less likely, but more concerning. The crack is due to excessive stress and it chose the weak link. If so, the crack will grow inward and eventually penetrate into the inner liner where the tire will fail suddenly and without warning, and likely while the vehicle is at high speed.

Given the severe nature of the second possibility, I'd recommend replacing the tire.