Weird wear in center of front tires only

[DeeRanger]

I sent the pics to a friend who's been in the tire industry for 35 yrs, this was his reply.

 

[Brain75]

That's an interesting "casting blame".... not being hostile, but it doesn't sound like the right answer to me. I've read the professional tire sites claim that as well, but I still don't buy it.

I grew up on a farm, and every vehicle we had drove dirt roads almost exclusively until I turned 14... I could name 6 fullsize ford trucks, 2 buicks, 1 jeep (wagoneer), 2 or 3 ford cars, and so many tractors I can't even name em all (almost all John Deere, but a few Newholland)... never have I seen anything even remotely like that from dirt roads, even during the winter when you are driving on frozen razor blades. When I turned 14, we switched schools to a place 30 miles away and the cars got 30% pave, 70% dirt - still none of that.

I've seen tractor tires throw chunks like that but they were 30 years old and sun rotted 365 days a year, they were just chunking out from old age. Most of that was outer edge, especially if you drove over a big rock.

The one time I have seen tires chewed up like that was brand new freshly rolled macadam - like following behind the steam roller fresh, across the whole tread though.

 

[RussAdams]

I sent the pics to a friend who's been in the tire industry for 35 yrs, this was his reply.View attachment 119943

That's really interesting. I can't remember driving on the dirt. Maybe when I first bought the truck. But not often and not fast.

Why front only?

 

[lil_Blue_Ford]

I’d bet that the answer is not dirt or gravel roads since we have already established that dirt/gravel is not in your daily or even weekly travels. If I had to guess, it’s probably a poor quality rubber or defect compounded by turning your wheels on pavement without moving and possibly a little too much tire pressure. People have forgotten how to be analytical and ask relevant questions to establish an answer and have moved to just blaming something.

Sitting in one spot on pavement and turning your wheels puts stress on everything and you are concentrating all of the vehicle weight on your contact patch. This can easily put wear on tires, especially when it’s hot out and the pavement is hot because you can actually tear small stones up from the pavement at times. I was taught to try to do as much steering as possible while the vehicle is rolling. I often palm the wheel and usually can go from lock to lock in less than two feet rolling slowly. If you have the window open, radio off, and good enough hearing, you can often listen to your power steering pump. Listen to the sound it makes turning while still and turning while rolling. It will be noticeably louder turning while sitting still because it has to work harder.

As for contact patch, the door sticker is a recommended pressure for the specific tires that came on the truck and a general recommendation for that particular tire size, but it’s not always accurate. My Choptop calls for 32-35 psi on the door sticker. That pressure in the 35” tires that are currently on it wears a dime sized contact patch and rides like you welded the axles to the frame. The old method for establishing proper contact patch and tire pressure is to draw a chalk line across your tread and drive on it. See where it wears and where it doesn’t. You want a minimum of 80% of the tread contacting the road. Reduce tire pressure until you achieve it. Really you should do this with any new set of tires. I run 10 psi in my Choptop tires on the road because that’s what it takes to get 80% across the tread. Yes, it even goes on the highway like that and in all the years I’ve run it, that pressure has not been a problem and I get great tread wear and great traction. I’m going to have to make a video on this…

 

[RussAdams]

The old method for establishing proper contact patch and tire pressure is to draw a chalk line across your tread and drive on it. See where it wears and where it doesn’t. You want a minimum of 80% of the tread contacting the road. Reduce tire pressure until you achieve it. Really you should do this with any new set of tires.

I run 10 psi in my Choptop tires on the road because that’s what it takes to get 80% across the tread.

I've never heard of this 80% rule. VERY interesting.

I'll give it a try when I get back home next week.

 

[85_Ranger4x4]

That's an interesting "casting blame".... not being hostile, but it doesn't sound like the right answer to me. I've read the professional tire sites claim that as well, but I still don't buy it.

I grew up on a farm, and every vehicle we had drove dirt roads almost exclusively until I turned 14... I could name 6 fullsize ford trucks, 2 buicks, 1 jeep (wagoneer), 2 or 3 ford cars, and so many tractors I can't even name em all (almost all John Deere, but a few Newholland)... never have I seen anything even remotely like that from dirt roads, even during the winter when you are driving on frozen razor blades. When I turned 14, we switched schools to a place 30 miles away and the cars got 30% pave, 70% dirt - still none of that.

Super common here, especially on 3/4 ton and heavier trucks. The gravel just chews the tread away.

"dirt roads" is kind of a blank term. Dirt itself doesn't really wear tires very fast but some people call gravel roads "dirt roads". Crushed limestone does chunk out tires. And lesser street tires gravel will puncture outright.

And grades of gravel vary wildly too, for awhile my county was getting a more yellow/orange limestone becuase it was cheaper. It also broke down much faster becauese it was softer and even stained white vehicles.

 

[lil_Blue_Ford]

I've never heard of this 80% rule. VERY interesting.

I'll give it a try when I get back home next week.

It’s not so much a rule as a sort of rule-of-thumb. The bigger your contact patch, the more tire surface available to grip whatever you are driving on, that’s why a lot of serious off-road guys like beadlock rims so they can air down to 2-8 PSI and not have to worry about losing a tire bead. The low tire pressure let’s the tire conform to the ground, increasing traction. It’s less of an issue on pavement, but it’s still an issue.

My F-150 I wear out the center of the tread and I accept that as part of the process since I use it to haul and tow a lot, so I keep the tire pressures up to handle that use, but I sacrifice grip on the road empty because of the higher pressure and smaller contact area. I could get more life and better performance out of a set of tires if I adjusted the tire pressure based on being empty or loaded, but without central tire inflation, it’s not overly practical. My Choptop and Ranger since they typically don’t get run as hard, I set the pressure to achieve a better wear on the tires and better traction.

Ideally you would want 100% of the tread width in contact with the road, but that isn’t always realistic, like with my Choptop. At 10 psi I’m barely at 80% roughly and I’m not super willing to try and get more. But 80% of a 12.5” wide tire is a lot of tread on the ground.

You are also lowering your ground pressure by spreading the load across more of the tread instead of concentrating it in one spot, so it really makes sense. Lower ground pressure, more traction, better tire wear.

 

[Curious Hound]

It’s not so much a rule as a sort of rule-of-thumb. The bigger your contact patch, the more tire surface available to grip whatever you are driving on, that’s why a lot of serious off-road guys like beadlock rims so they can air down to 2-8 PSI and not have to worry about losing a tire bead. The low tire pressure let’s the tire conform to the ground, increasing traction. It’s less of an issue on pavement, but it’s still an issue.

My F-150 I wear out the center of the tread and I accept that as part of the process since I use it to haul and tow a lot, so I keep the tire pressures up to handle that use, but I sacrifice grip on the road empty because of the higher pressure and smaller contact area. I could get more life and better performance out of a set of tires if I adjusted the tire pressure based on being empty or loaded, but without central tire inflation, it’s not overly practical. My Choptop and Ranger since they typically don’t get run as hard, I set the pressure to achieve a better wear on the tires and better traction.

Ideally you would want 100% of the tread width in contact with the road, but that isn’t always realistic, like with my Choptop. At 10 psi I’m barely at 80% roughly and I’m not super willing to try and get more. But 80% of a 12.5” wide tire is a lot of tread on the ground.

You are also lowering your ground pressure by spreading the load across more of the tread instead of concentrating it in one spot, so it really makes sense. Lower ground pressure, more traction, better tire wear.

Additionally, you don’t want too low of a pressure at highway speeds because that causes the tire to flex more and creates heat within the tire structure. Too much heat at high speeds can cause rapid tire disassembly.

 

[lil_Blue_Ford]

Additionally, you don’t want too low of a pressure at highway speeds because that causes the tire to flex more and creates heat within the tire structure. Too much heat at high speeds can cause rapid tire disassembly.

That’s why I don’t want to go below 10 psi on the Choptop. I think I’m probably flirting with the fine line there. It seems to handle the highway just fine as it sits without getting tires hot. Now that I have a temp gun, I’ll probably do some checking, but I’ve run 10-12 psi for years without any hint of a problem. Of course, it’s also not really a high speed rig, I’ll rarely get it over 70-75 on the highway because it’s just not really intended for that. It’s more comfortable around 65.

 

[85_Ranger4x4]

Additionally, you don’t want too low of a pressure at highway speeds because that causes the tire to flex more and creates heat within the tire structure. Too much heat at high speeds can cause rapid tire disassembly.

Had a guy come in for a tire vibration. Tire would not balance for crap. Tech broke it down and apparently they ran it low/flat and powdered the inside. They hit with a can of fix a flat which fixed the flat... and glued all the rubber powder into something resembling a football that was bouncing around inside the tire.

 

[ekrampitzjr]

Most of you have covered the most likely problems. By the way, several years ago Virginia implemented a statewide speed limit of 35 mph on dirt and gravel roads, and it doesn't have to be posted. Most unpaved roads are risky above about 25 mph anyway.

But here's another thought I'll throw out based on the wear. Could it be overinflation + worn/bad front bearings? Worn bearings can give some crazy wear, even if the truck isn't driven at highway speeds to make vibration noticeable. If not the bearings, check suspension bushings carefully too. Also, that frame is pretty rusty. Wouldn't hurt to check it while you're looking at the suspension.

 

[RussAdams]

Could it be overinflation + worn/bad front bearings? Worn bearings can give some crazy wear, even if the truck isn't driven at highway speeds to make vibration noticeable. If not the bearings, check suspension bushings carefully too. Also, that frame is pretty rusty. Wouldn't hurt to check it while you're looking at the suspension.

Thanks for these thoughts.

I've never overinflated the tires. If anything I have not been great at keeping them at 30 psi. Very slow leaks that I should keep closer attention. But... life.

I will definitely check the bearings and bushings. I did a lot of engine work lately and had the front wheels off a few times and didn't notice bearing play or noise. But I wasn't looking for it either. So I'll check.

The bushings could definitely be original. 240,000 miles. So yep I'll look there.

I have a couple quarts of por-15 in the garage for the frame. Lots of surface rust but the underlying structure looks sound.

Again thanks for the suggestions!

 

[RussAdams]

several years ago Virginia implemented a statewide speed limit of 35 mph on dirt and gravel roads, and it doesn't have to be posted.

I moved to Virginia about 10 years ago. I was unaware of this law. I'm unlikely to go over 35 on unpaved roads (or even be ON an unpaved road) but still good to know.

Thanks!