Road ruts

[motorheadmike]

No alignment is going to resolve the issue of a tire not being in contact with the pavement, or not equal and symmetrical contact from side to side.

A narrow tire is the solution or drive through it and hope that this is not the normal road condition you drive in.

FYI - the road is engineered to be flat.

Mostly flat, slight crown for water shedding.

Everyone still rocking 195s on factory14s:

They see me rollin', they hatin'...

 

[Supercharged111]

i disagree with you on the camber. i have found the best tire wear with a camber setting of +.5 degrees. my cars are street cars and see no road course time. if they did, i would agree with you and set my alignment completely different. but i would then realign it when i'm back on the street.


yes, like you, i have a couple of cars with 275 tires on the front. i find with tires this wide that factory alignment specs work best for me in reducing the effects of tramlining.
thanks for the reminder of the industry term "tramlining". here is info from tire rack concerning this. its a great read.

TRAMLINING: COPING WITH THE RUTS IN THE ROAD​

(Lea en español)
The term "tramlining" is being used to describe when directional control is disrupted by the vehicle's tendency to follow the longitudinal ruts and/or grooves in the road. Its name could be compared to the tram or trolley driver who does not steer because his vehicle follows the path established by the tracks.
Any vehicle can exhibit tramlining on certain areas of the highway because of uneven pavement or severe rutting. And all vehicles tramline to some degree rather than obediently following the driver's steering input. For example, there's usually at least a small change in steering resistance felt through the wheel when crossing an uneven expansion joint or asphalt junction during lane changes.
Noticeable increases in tramlining are frequently uncovered when drivers living in the snowbelt make the seasonal changeover from winter tires to summer tires, or when any driver upgrades the performance of their tires using either the same size or going to a "Plus Size" tire and wheel package. The reason that it becomes more pronounced then is because neither the typically narrower and softer handling winter tires nor the Original Equipment tires generate as much grip or responsiveness as the higher performance summer tires. Since the vehicle's suspension works as a complete package, a higher performance tire will also uncover any previously unnoticed looseness in the rest of the suspension.

Components​

Tires have the most direct influence on tramlining because they are the part of the vehicle that comes into contact with the road (and the longitudinal ruts and/or grooves that exist there). Unfortunately anything that increases a high performance tire's responsiveness also increases its willingness to tramline.
High performance tires with short sidewalls that develop lots of cornering power at lower slip angles will be more susceptible to tramlining than standard All-Season passenger tires that develop less cornering force until their slip angle increases. A wider treaded tire will encounter more longitudinal ruts and/or grooves in the road than a narrow treaded tire. A tire with large tread blocks that transmits the driver's input to the road with great precision will also transmit the road's imperfections back to the vehicle's suspension. And because tires become more responsive as their tread depth wears away (which is why tires are shaved for competition and track use), a tire will become more likely to tramline as it wears.
Wheels can influence tramlining as well. Installing wider tires or a "Plus Size" tire and wheel package usually requires using wheels with a different offset than the vehicle's original wheels. In some cases, the new wheels will have slightly less offset than the original and in other cases, slightly more. It all depends on the vehicle's suspension design and available wheelwell clearances. You will even find that Original Equipment manufacturers often use different wheel offsets for their different diameter tire and wheel packages.
Usually the amount of offset change is kept to a minimum and vehicle tracking remains relatively unchanged. However if the offset is significantly different, it will alter the way the road forces are transmitted through the tire and wheel to the suspension. Therefore, large changes in wheel offset will increase the likelihood of tramlining.
Suspension bushings, ball joints and shock absorber mounts have a direct influence on tramlining as well. As miles are driven and the years go by, the suspension's wear parts will deteriorate as they age. This often happens so slowly that it isn't very noticeable. Over time the ever-increasing suspension wear permits play that eventually allows the tire to be directed by the irregularities of the road rather than be controlled by the suspension.
Imagine a worn suspension that allows a front wheel and tire to swing between the recommended 1/16-inch of toe-in and 1/16-inch of toe-out when it encounters a rut in the road. This 1/8-inch difference in the direction that the tire is pointed will result in the vehicle tramlining. Replace the worn part to remove the play and you will significantly reduce or remove the tramlining. Many drivers with higher mileage cars have reported that replacing worn suspension components has eliminated tramlining and made the car drive like it is new again...which I guess it essentially is!

Service Adjustments​

Using higher tire pressures than recommended by the vehicle manufacturer for your driving conditions will unnecessarily stiffen the tire and make it even more willing to cause tramlining. If you are running higher tire pressures than necessary, simply dropping the tire pressures to those recommended by the vehicle manufacturer will help reduce tramlining.
Alignment settings can be key as well. The "camber" and "toe" settings both play a role in vehicle stability and the propensity for tramlining. Extreme positive or negative camber settings will make a vehicle more sensitive, especially when only one wheel encounters a longitudinal rut and/or groove at a time. Even if all the tires are "aimed" straight ahead when the vehicle is in motion, a tire that is "cambered" wants to turn. This is the result of the "camber thrust" generated by a leaning tire (it is also part of the explanation of how motorcycles turn). A vehicle suspension using lots of negative camber for competition or the track will experience more tramlining on the street.
Additionally, the drivers who use additional toe-out settings to encourage their vehicle to turn into corners better also encourage tramlining because the extra toe-out will reduce vehicle stability in a straight line.
In the case of the competition driver who uses non-factory alignment settings, the amount of tramlining that is acceptable has to be left up to the driver. For only street-driven cars, getting them aligned with negative camber and toe settings within the factory's specifications is an important first step.

Roads​

On a multi-lane highway, usually the left lane offers the smoothest road surface because it sees the least amount of heavy truck traffic. Unfortunately, on many interstate highways, it's not legal to continually drive there (pull right except to pass). While the center lane can be almost as smooth on a six-lane highway, there can be exceptions. For example, in the case of I-94 between Chicago and Milwaukee, you will find that when the road was widened from two to three lanes, the center of the new center lane is on top of the original junction between the earlier two lanes. This means that vehicles traveling in the new center lane have their right hand tires on the original right hand truck lane and their left side tires are on the original left lane. This can cause an uncomfortable feeling for miles. Usually the right hand lanes are the least smooth because they are rutted by heavy truck traffic. When you drive in those lanes, or drive across them to exit the highway, it's possible that you'll find your vehicle may feel like it wants to follow the truck ruts and has a mind of its own.

Driving Style​

If you experience tramlining, the main thing you want to remember is to keep both hands on the steering wheel in the proper "9- and 3-o'clock" positions. This will help you make the precise steering inputs that will help keep your vehicle on course. You sacrifice precise control if you drive with one hand on the wheel or both hands in the wrong place.

I cannot fathom the concept of positive camber. You're going to have to enlighten me. .5 degrees isn't jack $hjt for camber, nothing remotely aggressive. For aggressive use you'll want no less than -2 negative, I run -3 in my Camaro with him joints. You go around a corner even driving like an old man and the tire is gonna lean out. At no point will it lean back in when it's set with positive camber. I fail to comprehend how this is best for tire wear. Since you have observed this, hopefully you can explain why.

 

[oldsmobile joe]

i can't speak for you, but i'm not a mechanical engineer and i didn't stay in a Holiday Inn Express lately. the O.P. asked if there is a way to minimize the tramlining his vehicle is experiencing on his local roads. my recommendation was based on facts from the gm service manual, years of running my personal wide tire car that i personally aligned and backed up by the info from Tire Rack, a successful tire sales company.

I cannot fathom the concept of positive camber.

i don't know what to say, is this too much? not enough? what? please tell us. you've told me twice that i'm wrong. but offer nothing specific on how to alleviate the O.P.'s concern. what you have offered is vague and ambiguous.

 

[Supercharged111]

i can't speak for you, but i'm not a mechanical engineer and i didn't stay in a Holiday Inn Express lately. the O.P. asked if there is a way to minimize the tramlining his vehicle is experiencing on his local roads. my recommendation was based on facts from the gm service manual, years of running my personal wide tire car that i personally aligned and backed up by the info from Tire Rack, a successful tire sales company.

i don't know what to say, is this too much? not enough? what? please tell us. you've told me twice that i'm wrong. but offer nothing specific on how to alleviate the O.P.'s concern. what you have offered is vague and ambiguous.

I read your post to say you found optimum tire wear with positive camber. With positive camber, the top of the tire is ALWAYS canted outward. With light negative camber, it will be canted in in a straight line and out around a corner, essentially splitting the middle to even out the tire wear.

 

[oldsmobile joe]

With positive camber, the top of the tire is ALWAYS canted outward. With light negative camber, it will be canted in in a straight line and out around a corner, essentially splitting the middle to even out the tire wear.

ah, now i understand where your coming from. this is not how front tires perform. most tires travel in a straight line far more than they turn or corner. so there is no 50/50 split of straight line vs cornering. when tires do turn or corner on our gbody cars, you are correct, the outside tire will move up and go more positive, but inversely, the inside tire will drop and go negative. hmm. however, to show tire wear from this alone would require extreme vehicle pitch. when it comes to tire wear from cornering, most comes from when the outside tire shoulder starts to fold over. just as a shoe salesperson can tell how you walk, i can tell how a person drives their car by looking at their tire wear. freeway drivers will have tires with square shoulders front and rear. city drivers will have tires that have rounded shoulders and in particular the left front tire. left front tires will show the most wear, due to right hand turns are sharper (smaller radius) compared to left handed turns that generally are more gradual (greater radius).
to get to to your questions concerning +.5 vs -.5 camber. i don't know what to say. there's alot that goes into determining alignment specs, front to rear weight bias, front wheel drive vs rear wheel drive, scrub radius, steering axis inclination, caster, camber, ackerman. from my limited experience, rear wheel drive cars run generally run positive camber and front wheel drive cars generally run negative camber. i'm sure there are exceptions to this, but this is what i know from wrenching on toyotas for 14 years as well as owning and aligning my 57 olds, 66 belair and my gbodies.
hope this helps.

 

[Supercharged111]

I run no less than -.5 on anything I own and never see excessive inner wear. I've been doing my own alignments for years. This includes my pickup trucks and the wifemobile. If anything, we see slightly more outer wear than inner. Apparently we take corners faster than most. Again, if a tire ALWAYS cants out I just cannot fathom even tire wear. A lot of the variables you cited can be completely overridden by driving style. Hardly anyone pushes their car to the point they truly discover the balance of the car's limit. The outer tire takes an order of magnitude more of a pounding than the inner. Our driving is mostly mixed, but a lot of in town driving still happens around 50-60 with corners. When I go back home to upper MI, the driving experience is completely different.

 

[oldsmobile joe]

I run no less than -.5 on anything I own and never see excessive inner wear. I've been doing my own alignments for years. This includes my pickup trucks and the wifemobile. If anything, we see slightly more outer wear than inner. Apparently we take corners faster than most. Again, if a tire ALWAYS cants out I just cannot fathom even tire wear. A lot of the variables you cited can be completely overridden by driving style. Hardly anyone pushes their car to the point they truly discover the balance of the car's limit. The outer tire takes an order of magnitude more of a pounding than the inner. Our driving is mostly mixed, but a lot of in town driving still happens around 50-60 with corners. When I go back home to upper MI, the driving experience is completely different.

i'm glad you found something that works for you.

 

[Supercharged111]

i'm glad you found something that works for you.

The point I feebly attempted to make at the end was how, if I lived somewhere else, I may not need as much negative camber to even out the tire wear.

 

[Dayzedandkonfuzed]

Well at the very least I learned that it's called tramlining. As for the rest...