Odd rear tire wear

[kellyrus408]

I have a 2007 SEL that has treated me well, except the insides of the rear tires start scalloping and become noticeable after 15K miles. By 30K they are junk. I've been to two tires shops and they have both told me the same thing...I'm not carrying enough weight? HUH? They also recommend rotating which I have never done with tires. Seems to me I have a different problem then how much weight I'm carrying (normally there is nothing back there, but at times I'll load it up with 400+ lbs of "toys"), and I'm reluctant to start rotating now until my issue is properly diagnosed.

 

I keep my tires inflated at 35psi, and the fronts will last me 40K!

 

Any thoughts?

[Mr. Westfield]

WHAT? Never rotated tires?

 

Never heard of such a thing. Buy new tires, rotate them every 6-8 thousand miles and never have this issue again.

[kellyrus408]

Nope, never ever rotated tires the "traditional" way in my life. When the fronts wear out I buy new tires and rotate the rears to the front. The point here is why are the inside of the rear tires cupping/scalloping? I don't need 4 tires that are cupped.

Edited July 11, 2010 by kellyrus408

[akirby]

WHAT? Never rotated tires?

 

Never heard of such a thing. Buy new tires, rotate them every 6-8 thousand miles and never have this issue again.

 

Rotation doesn't fix that kind of problem - it just spreads it out over 4 tires instead of 2.

 

Cupping typically indicates a shock or strut problem. Are your roads really bad?

[blumi]

I suggest to get your rear wheel alignment checked.

 

Bastian

[ablb]

If you’re getting 40K out of a set of FRONT tires without rotating :happy feet: NEVER let an alignment shop touch the front end!

 

Like akirby and blumi you need to take your Edge to an Alignment, NOT tire shop!

 

ab

[kellyrus408]

Rotation doesn't fix that kind of problem - it just spreads it out over 4 tires instead of 2.

 

Cupping typically indicates a shock or strut problem. Are your roads really bad?

 

I wouldn't say the roads are any worse than many other states. I live in South Carolina and I'm pretty careful about missing potholes, etc. I would think a strut problem wouldn't limit the cupping to the inner edge of the tires.

 

While the tire shops I spoke with also do alignments (one NTB and the other a Goodyear store), they never mentioned an alignment. One did say to dismount the tires and put the cupped edge on the outside! That's why I posted here!

[akirby]

Check the rear camber, shocks and wheel bearings in that order. Rotating often should keep the cupping to a minimum and allow you to get more life out of the entire set of tires.

[flyerjmr33]

A combination of things could cause the cupping--- Balance would be my first pick. Weak shocks number 2 if we were looking at something mechanical. Rear toe would also have to be considered. No amount of repair will eliminate the tire cupping once it is there. It is aggrivated by not rotating the tires at a 5-7000 mile interval.

I spent 28 years working for an alignment equipment manfacturer and what you need is an alignment specialist--- not a tire store that employs folks at minimum wage. I'm very surprised that neither the Goodyear store or NTB tried to get you on the alignment machine. That alone indicates to me that they are lacking knowledge and are more "tire busters" than anything else.

 

I recommend that you replace those cupped tires and have all the things I mentioned checked. Then get on a rotation schedule or you'll have the same problem all over again. The chassis on these newer vehicles with independant suspension is a lot more sensitive to slight errors in adjustment specs than your vehicles of years past.

[kellyrus408]

I'm discounting balancing because these tires came off the front where I got 38K miles of perfect wear. If they were unbalanced on the rear it should have showed up on the front, no? Plus, they are wearing in the same spot...inside edge.

 

No one commented on the idea that I don't carry enough weight to compensate for the engineering. That was the one thing both shops were in agreement with.

[flyerjmr33]

I'm discounting balancing because these tires came off the front where I got 38K miles of perfect wear. If they were unbalanced on the rear it should have showed up on the front, no? Plus, they are wearing in the same spot...inside edge.

 

No one commented on the idea that I don't carry enough weight to compensate for the engineering. That was the one thing both shops were in agreement with.

 

 

Why are you asking what's wrong? Seems to me like you have already made your diagnosis. You asked for help and when you don't take the recommendations of folks who are experienced professionals in the business, you are wasting time & effort on their part.

 

ONE MORE TIME______ You need an alignment expert (not a tire shop) to check this vehicle over. What part of that don't you understand?

Edited July 18, 2010 by flyerjmr33

[kellyrus408]

Why are you asking what's wrong? Seems to me like you have already made your diagnosis. You asked for help and when you don't take the recommendations of folks who are experienced professionals in the business, you are wasting time & effort on their part.

 

ONE MORE TIME______ You need an alignment expert (not a tire shop) to check this vehicle over. What part of that don't you understand?

 

I'm sorry, I didn't realize YOU had the final say. If you don't like my questions don't respond. If you think I'm wasting your time, then you must have time to waste. Chill out.

[flyerjmr33]

I'm sorry, I didn't realize YOU had the final say. If you don't like my questions don't respond. If you think I'm wasting your time, then you must have time to waste. Chill out.

 

I definitely do have time to waste, but not on folks who can't or won't take advice from professionals-- It's tough to confuse you with facts when your mind is made up. It's your vehicle and suggest that you do as you please with it-- you are under no obligation here other than to say thanks to those who give you decent advice.

Edited August 14, 2010 by flyerjmr33

[akirby]

The point is - if you ask a question then you should be willing to accept the advice given, not ignore it or argue with it. If you don't want advice then don't ask.

[ablb]

I definitely do have time to waste, but not on folks who can't or won't take advice from professionals-- It's tough to confuse you with facts when your mind is made up. It's your vehicle and suggest that you do as you please with it-- you are under no obligation here other than to say thanks to those who give you decent advice.

 

http://www.bullyonline.org/related/cyber.htm

[L1TECH]

Tire cupping is caused by 2 things.1) out of balance tires, just because they felt fine on the front deosn't mean that they should be fine on the rear. 2) Weak shocks/struts. I don't know how many miles you have on yoru Edge but the factory shocks/struts are junk after about 20-25k miles, you just don't realize it because you have become used to the slow degradation over time. Rotating the tires should be done every oil change and on my personal vehicle that includes balancing. I just had to change my oil for the first time last week, 4900 miles, at that time I rotated and balanced the tires and 3 of the 4 tires were out of balance although the ride was still smooth. Alignment should be checked but if you have true cupping it is not due to alignment,. tire cupping is caused by the tires bouncing uncontrolled on the road surtface due to worn shocks/struts or out of balance, an alignment issue will not cause the tire to bounce. I have been an ASE master tech for 22 years now and trust me there is no other reason for tire cupping than what I have explained to you.

[flyerjmr33]

Tire cupping is caused by 2 things.1) out of balance tires, just because they felt fine on the front deosn't mean that they should be fine on the rear. 2) Weak shocks/struts. I don't know how many miles you have on yoru Edge but the factory shocks/struts are junk after about 20-25k miles, you just don't realize it because you have become used to the slow degradation over time. Rotating the tires should be done every oil change and on my personal vehicle that includes balancing. I just had to change my oil for the first time last week, 4900 miles, at that time I rotated and balanced the tires and 3 of the 4 tires were out of balance although the ride was still smooth. Alignment should be checked but if you have true cupping it is not due to alignment,. tire cupping is caused by the tires bouncing uncontrolled on the road surtface due to worn shocks/struts or out of balance, an alignment issue will not cause the tire to bounce. I have been an ASE master tech for 22 years now and trust me there is no other reason for tire cupping than what I have explained to you.

 

He's been told the same thing about 4 times now---

[flyerjmr33]

http://www.bullyonline.org/related/cyber.htm

 

There's a definite difference between bullying and facts---

[Sparky]

Tire cupping is caused by 2 things.1) out of balance tires, just because they felt fine on the front deosn't mean that they should be fine on the rear. 2) Weak shocks/struts. I don't know how many miles you have on yoru Edge but the factory shocks/struts are junk after about 20-25k miles, you just don't realize it because you have become used to the slow degradation over time. Rotating the tires should be done every oil change and on my personal vehicle that includes balancing. I just had to change my oil for the first time last week, 4900 miles, at that time I rotated and balanced the tires and 3 of the 4 tires were out of balance although the ride was still smooth. Alignment should be checked but if you have true cupping it is not due to alignment,. tire cupping is caused by the tires bouncing uncontrolled on the road surtface due to worn shocks/struts or out of balance, an alignment issue will not cause the tire to bounce. I have been an ASE master tech for 22 years now and trust me there is no other reason for tire cupping than what I have explained to you.

I do not believe the factory shocks/struts are junk after about 20-25k miles, we should all get them replaced through bumper to bumper warranty ....., it is not making sense to me. :yup:

[L1TECH]

I do not believe the factory shocks/struts are junk after about 20-25k miles, we should all get them replaced through bumper to bumper warranty ....., it is not making sense to me. :yup:

 

 

I am not trying to make you believe it, just stating my opinion based on my personal and my customers experiences. Like I said before the thing with shocks/struts is that they degrade slowly over time so the person driving the vehicle never even notices it until new ones are installed. As far as getting them warrantied that is another issue. Any mechanic worth a dam knows exactly what causes tire cupping but in the mfgs eyes unless the shock/strut is visibly leaking or has a mechanical defect they will not replace it, they will blame the tire wear on other issues and by time that you have figured out they are wrong the vehicle is out of warranty.

[akirby]

I am not trying to make you believe it, just stating my opinion based on my personal and my customers experiences. Like I said before the thing with shocks/struts is that they degrade slowly over time so the person driving the vehicle never even notices it until new ones are installed. As far as getting them warrantied that is another issue. Any mechanic worth a dam knows exactly what causes tire cupping but in the mfgs eyes unless the shock/strut is visibly leaking or has a mechanical defect they will not replace it, they will blame the tire wear on other issues and by time that you have figured out they are wrong the vehicle is out of warranty.

 

There is also a big difference between a vehicle driven daily on bad roads vs. one driven exclusively on smooth interstates.

[flyerjmr33]

There is also a big difference between a vehicle driven daily on bad roads vs. one driven exclusively on smooth interstates.

 

Years ago, shocks would wear out at about 40,000 miles. Today's shocks & struts will go to about 80,000 under average driving conditions without any problem. Of course, if you don't carry enough of a load in the back(tongue in ckeek), you could have "early shockitis" and failure from lack of exercise!

"

[L1TECH]

^^^^^

 

Sorry but todays shocks/struts do not last 80,000 miles. Both of my last 2 new vehicles needed shocks/struts at around 22,000 miles. Both vehicles were Fords and both vehicles were driven by the wife back and forth to work on paved roads that are extremely smooth. Shocks/struts are and will continue to be the most overlooked item on a vehicle. And just for the record the Edge, along with any other vehicle, should never have to have weight in the back of it to keep the tires from wearing abnormally.

[flyerjmr33]

^^^^^

 

Sorry but todays shocks/struts do not last 80,000 miles. Both of my last 2 new vehicles needed shocks/struts at around 22,000 miles. Both vehicles were Fords and both vehicles were driven by the wife back and forth to work on paved roads that are extremely smooth. Shocks/struts are and will continue to be the most overlooked item on a vehicle. And just for the record the Edge, along with any other vehicle, should never have to have weight in the back of it to keep the tires from wearing abnormally.

 

Did you put OE shocks back on the vehicles? If so, they should have been covered under the 3-36 warranty--- and if Fords need that kind of TLC, everyone should buy something other than a Ford. 22,000 miles of use on a shock should just get it broken in---- There are shocks available with lifetime warranties, you know

 

http://www.allshocks.com/bilstein/html/why_bilstein.html

[L1TECH]

The last vehicle we had, A 2008 Ford Sport Trac, at about 20,000 miles had started to chop the tires pretty bad and couldn't handle the speed rollers in our neighborhood with out he front and rear slamming loudly on the suspension rebound. No aftermarket company currently makes a replacement shock/strut for the 3rd genetration Sport Trac so that is othe only reason I took it back to Ford. As expected Ford found no issues, so myself along with the service manager drove a new one off of the lot which behaved very differently than mine under the same circumstances...they tried to tell me that mine was broken in is all. Like I said before people don't realize the slow degradation of the suspension because they get used to it and I don't mean to imply that all shocks/struts need replacing at 20,000 ish miles but no vehicle built will perform suspension wise at 80,000 miles like it did when new.

 

I am an ASE master technician of 22 years now and believe me when I tell you that I am fully aware of how suspensions are supposed to react and what problems arise from worn suspension parts, i also am very well informed on the parts situation but let me just say this. If you are buying parts for your vehicle that have a lifetime warranty then you are making a huge mistake. Only parts companies who make cheap products and sell them for a premium price warranty their products for life against all problems. Sure every company backs their product against flaws in workmanship but a shock or strut wearing out is not a flaw in workmanship it's a natural occurance that is going to happen and there is nothing you can do to change that. BTW Bilstein is not the company it once was