New tires, out of round?

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May 4, 2008
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Just finished a set of Defender LTX‘s on my 02 Envoy, lasted 74K miles to the wear bars. Those tires were purchased at Costco and I had zero issues.

I replaced with a fresh set from Costco again, this time I had a shake around 30 MPH and figured it could have been a flat spot from being parked all night

Next day I felt the same thing, could also feel it in the cabin at hwy speeds. I jacked up the vehicle and watched the tires and there was a noticeable hop of the tire, more pronounced in the LR.

I took it back and they rebalanced all 4 tires and same result. They ended up changing the LR and the morning hop was gone. Now I feel the steering wheel shake at 60 MPH and I raised all 4 tires, placed in 4HI, and the LF appears out of round as well. The tire has about a 1/8” rise at one point, maybe this is normal?

I never paid much attention to the last set as they were smooth for the life of the tire. Back in the day when I changed tires, I don’t remember a new tire being noticeably out of round.

I figured these new tires had a separation, not sure, I didn’t hit anything, no hard braking, only driving to and from work, no impacts or even speed bumps.
Both rear axle shafts are new GM units, about 3 years old, both hub and bearings are less than 1 year old.
 
i've seen lots of out of round tires lately. you can ask them to road force ballance them, and also ask what the road force numbers are. don't accept anything over 10. heck even over 7 i refuse the tire.
 
I suggest finding a reputable tire shop and have them take a look at them. The big box stores just don't have the skill level and knowledge that a legitimate tire shop does due to it being their bread and butter. Not so for Costco.
 
Make them replace it. Don’t fool with trying to have it road force balanced. You can’t balance an egg.
 
There's no audio, but this is the tire in question. I tried to get a good point of reference just below the upper ball joint.

This was 10 min after about 60 miles of driving. Maybe I'm over thinking this, let me know what you think.

 
Most likely just poor install. Most of the time when I see excessive roadforce, I just pop the bead, inflate and spin it again. Most of the time the roadforce will be greatly reduced.
 
I suggest finding a reputable tire shop and have them take a look at them. The big box stores just don't have the skill level and knowledge that a legitimate tire shop does due to it being their bread and butter. Not so for Costco.
Costco doesn't have Road Force machine

...part of the reason I don't get tires from them anymore

They can barely handle tread life warranty claims, nevermind run out, out of round, or anything other than the most basic of mounting and balancing
 
I worked in a tire shop years ago and it seems that out of round tires have been around to some degree. We would 'true/shave' them if out more than 0.030". We had a dial indicator with a wheel pickup that had a mount provision on our spin balancer. I guess 'road force' compensates, but I like round to begin with. A shop nearby has an old truer that is nice to have around as most shops don't and some have never heard of them.
 
The industry as a whole is having problems making tires perfectly round. You'd think they got it down. I just put Nitto Terra-Grappler G2's on a 2013 Jeep Grand Cherokee. Had to balance them twice. The first time, I mounted and balanced them on my own since I work at a shop, and they vibrated above 60 MPH. I removed the old weights before balancing, and I put the yellow dots near the valve stems. Second time, I let Discount Tire balance them since they have better machines. It improved, but now I notice the vibration depends on the road I'm on. Most of the time it's smooth on the highway, but sometimes it starts vibrating in the steering wheel a bit as the road surface changes! I'm just gonna have to live with it since it depends on the road surface. The air shocks are still good. Maybe the tires will wear-in and make the ride smoother. All tires are at 40 PSI. Vehicle weighs like 5300 LBS, so I inflate them like it's a truck. Never had this problem with the old Goodyear Wrangler Silent Armor tires.
 
Also Check lug nut torque... So I just found out Discount Tire went a bit crazy with the impact gun on our Jeep. Some nuts were torqued well above 150. Had to loosen all the lug nuts and grabbed my Snap-On torque wrench from work. Went over each wheel twice in a star pattern at 110 ft lbs as stated in owner's manual. Test drove vehicle and vibration is gone. Let a shop do this for you real quick and see what it does.
 
Allow me to explain about Out of Round tires.

The technical term is Uniformity, where both the physical dimensions (Runout) and the tire stiffness variation are combined. The measurement is force and sometimes the term “Force Variation” is used to describe the phenomenon.

If you measure a loaded tire at the axle, you can plot the amount of force variation In pounds) around the tire’s circumference. Interestingly, you can break down the force variation (mathematically) around a tire into a series of Sine waves – once per revolution, twice per revolution, etc. We refer to these as 1st Harmonic, second Harmonic, etc..

It turns out that a vehicle’s suspension is a Spring-Mass-Damper system and those have resonant frequencies where the mass vibrates as though the damper (shock) is not there. In cars, that usually occurs in the 50 to 70 mph range.

So if the 1st Harmonic is high enough, it can be detected by a human in spite of all the other vibrations that a vehicle makes. This is particularly true when the road is very smooth.

One way to deal with this is to match the high point of 1st harmonic of the tire to the low point of the 1st harmonic of the wheel. The net effect is an assembly that is overall “Rounder”. That’s what the Hunter Engineering RoadForce machines do.

In the case of wheels the 1st harmonic peak generally occurs very close to the max runout point. This is not as true for tires, so the old idea of “Trueing” a tire didn’t work as well as it should have.

So why can’t tire manufacturers make tires round? Because of the way they are manufactured.

First, the tire molds are heated and cooled – and the metal warps. Second, tires are made in a series of layers where each layer has an overlap (called a splice) Each splice adds a bit of variation to the uniformity.

Further, over the years, cars have been made stiffer and stiffer and that makes the vehicle more sensitive to vibrations.

Ergo, it is a lot easier to make a vehicle twice as stiff than it is to improve the tire making process to reduce the force variation by half.

Yes, tire uniformity has always been there as has vehicle sensitivity, but vehicle sensitivity has progressed much more rapidly than improvement in tire uniformity.
 
Allow me to explain about Out of Round tires.

The technical term is Uniformity, where both the physical dimensions (Runout) and the tire stiffness variation are combined. The measurement is force and sometimes the term “Force Variation” is used to describe the phenomenon.

If you measure a loaded tire at the axle, you can plot the amount of force variation In pounds) around the tire’s circumference. Interestingly, you can break down the force variation (mathematically) around a tire into a series of Sine waves – once per revolution, twice per revolution, etc. We refer to these as 1st Harmonic, second Harmonic, etc..

It turns out that a vehicle’s suspension is a Spring-Mass-Damper system and those have resonant frequencies where the mass vibrates as though the damper (shock) is not there. In cars, that usually occurs in the 50 to 70 mph range.

Preach It !!

That's what I was saying on some of the other shock/suspension threads.

Lot more o it than many people think
 
So, ultimately, they sold you seconds that may never smooth out. So as CapriRacer suggests, see if they'll Road Force Balance on a Hunter machine. Get them down below 10 pounds road force if possible. Ergo, they're junk.
 
+2, take them back. What does costco have for a satisfaction guarantee?

If the store sends enough duds back to corporate it will get noticed and fixed.
 
How is your tire white in the video? If you pay for michelin you should get the best ride quality.
 
Thanks for the tips, it's starting to look like I'm going to ask for a fresh set.

How is your tire white in the video

I believe the cell phone camera was compensating for the dark background of the fender well and thus overexposing the tire.


What does costco have for a satisfaction guarantee?
They are working with me on these tires, have been cooperative, we will see what happens this weekend when I go back in for the vibration in the front.

For the record, within the last few months, both shocks and struts are new Blistein HD, 4 new OE springs, lower strut bushings, steering rack and tie rod ends. Within the last 2 years, upper and lower ball joints, lower control arm bushings, upper control arm bushings, both front hub and bearings, sway bar links and bushings. The suspension is "almost" as tight and free of slop as it was when new.

Sorry for posting this video late, but this is the LR tire that started this entire episode. This tire was replaced last week by Costco which fixed the felt "hop" in the cabin at low speeds as well as a good shake at hwy speeds.

 
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There's no audio, but this is the tire in question. I tried to get a good point of reference just below the upper ball joint.

This was 10 min after about 60 miles of driving. Maybe I'm over thinking this, let me know what you think.


Thats not bad at all.
My new Bridgstones bought at costco are worse than that but smooth on the road.
 
Thats not bad at all.
My new Bridgstones bought at costco are worse than that but smooth on the road.

I agree the front isn't terrible, but they were just balanced..(again) and the wheel shakes visibly at 65 mph. Before the LR tire was replaced, the steering wheel was steady even at 75 MPH.

Hopefully this is just a balance issue this time, maybe it's their machines. I do wish they had road force balancers. Last ditch effort will be another location to fix the balance.
 
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