Inside tire wear

You can estimate the toe situation by drawing a dot on the front of each front tire, center of the tread, then use a plumb bob to transfer the dot to the floor. Now move the vehicle forward enough the marks are at the rear of the tires. Again xfer the marks to the floor. Measure the two distances (front and rear) between the marks and let us know what you measure. Do this on a flat level surface for best results. No matter how accurate the alignment is, it won’t work if there’s any looseness in the suspension/steering system or wheel bearings.

@George_San_Jose1 - something tells me that the delta you are trying to find here is much-much smaller than the error in the measurements using this method

I’d guess. if done carefully, a measuring accuracy of 1/10 of an inch. Is that accurate enough for an estimate?

No , this thing needs to be on a machine that is certified to be accurate . One shop has stated that it is fine so chalk marks and measuring tapes are just not goint to solve this.

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Especially when you’re trying to figure out what’s wrong when one shop said it was ok. That requires a printout of all the measurements, not just a rough estimate of toe in.

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I got the printout of the alignment. Everything says it’s where it is supposed to be. I don’t know what most of it means though.

take a picture of it and upload it. @CapriRacer and others can help to explain what it means

Looks ok to me. It says it allows for a (front) toe range of 0.4 deg. For a 20 inch diameter tire, by my back of the envelope calculation you’d have to be able to measure to an accuracy of around 0.4 inches to do the experiment I mentioned above. Not suggesting there’s a need to do it at this point, its already been done.

All the alignment shop can do is check the static measurements. No way to check it while the car is driving down the road. Suspension system problems or even just tire problems could still be the culprit for your unusual tire wear.

You say your wife is an aggressive driver but I’m having a hard time seeing that as being the cause of this problem. If she is cornering hard enough to wear rubber off the inside edge of one tire then logic would dictate she would be scrubbing rubber off of the outer edge of the tire on the other side.

My late wife was an aggressive driver of sorts and we never had that problem with any vehicle we have ever owned.

Do you know if they inspected suspension/steering components or wheel bearings for looseness? Even a miniscule amount of slop can throw readings off or change while in motion.

I might have a bit of an issue with the given camber readings from the factory. Shown is almost half a degree - on one side and more than a half - on the other side. A half a degree is quite a bit and I would be inclined to want those to be in a more upright position given the chewing up tires fast situation.

There are various methods for changing the camber although I am not that familiar with Jeeps. Sometimes it’s as cheap as a few eccentric bolts up through eccentric ball joints and control arms. Hopefully not the latter 2.

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If you jack it up can you move the wheel with your hands and try to feel for any play in the suspension? Bad ball joints or tie rod ends will let the wheel move a little bit. You might be able to feel it in the steering wheel too, especially if the good side is jacked up.

I think when you adjust the alignment it’s due to hitting a pothole and bending something or parts wearing out. The alignment doesn’t just go bad on its own after years of driving. So just fixing the alignment doesn’t really solve the problem completely. On front wheel drive the wheels will toe in due to engine power. So if you adjust for that then when you’re coasting they’ll toe out and start wearing again.

All the suspension seems fine. I will just watch the tires closely. I thought she was trading it in. But since there is a car shortage and everything is expensive, she wants to wait a little longer. I really hate the Jeep. It eats rotors like crazy. It’s on the fourth set. She has had Mazdas, Subarus, a Buick, and a VW since we were married and none have needed rotors like the Jeep.

I perform a half dozen alignments each month, many are on the same make/model. The alignment on each car is off by about the same amount for the age of the vehicle, very little, the tire wear differs greatly from car to car.

Mr. Jones has even tire wear after 50,000 miles, even with -1.0 degree of camber. Mrs. Jones drives the same car and has tires with severe inner tire damage after 20,000 miles. She complains about the grinding noise from the tires while trying to park the car.

Some late model vehicles have a turning radius that is smaller than is practical and cause scuffing of the tires, repeated parking lot maneuvers can damage tires.

No adjustments were made, the before and after measurements are the same.

There are many rubber bushings in the suspension, sagging/settling in the suspension causes change in the alignment every few years.

That’s just not the way it works.

Between body lean and Akermann (Look it up!), most cars, when driven aggressively, wear the tire’s inside shoulder. I usually recommend using a higher pressure ( 3 to 5 more psi), since it is much less expensive than stiffer springs and a larger sway bar and a lot easier than trying to change an aggressive driver.

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I am familiar with the Ackermann Effect but just do not buy into his wife’s driving habits being the cause. All of my vehicles generally get 300k miles on them before being retired. One of them at 410k miles. With a wife who drives aggressively then why never an issue with any tire wear on any of those cars? RWD, FWD, 4WD, and of many makes.

Note the spec given is .1 to .9 negative. That is almost a full degree. Maybe my opinion is skewed a bit because of the cars I’ve worked on (very few Jeeps) but anytime I’ve done an alignment with specs like that with inner tire wear then that camber is going to be set as close as possible to upright.

CapriRacer; you have said yourself multiple times on this forum that you do not agree with the manufacturer alignment specs and feel that they are too broad. I fully agree, but you know why they are that way. Assembly line work and those cars do not go on alignment rack before being shipped out.

Aggressive braking causes the nose to fitfully tip down & stresses the suspension system’s components. Could be related.

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Opinions vary and that is fine. I know if this vehicle were mine I would move that camber to .1 or even 0 and add about 5 minutes of toe in.

FWIW, I note that MOOG offers a camber kit (40 bucks) for this vehicle. If the aftermarket is providing it then that means there is a somewhat substantial market for it as MOOG is not going to produce a few hundred copies and call it quits.

None of the other vehicles she had went through rotors like the Jeep. She put 110,000 miles on a Subaru Forester and it only had the rotors changed once. It was smooth. No vibration or anything. The Jeep needs rotors every 15,000 miles. Especially the rear ones. Same goes for the alignment. She never had alignment issues with any other vehicle she had.

I suggest trying a different brand of rotor next time, and make sure the calipers aren’t dragging excessively.

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They have had a few different ones. I tried different brake pads also. The original ones on it when it what new only lasted probably 12,000 miles before it was vibrating pretty bad hitting the pedal.