Check your toe and tire pressures.....

[suspectnumber961]

Redid the alignment on my focus and found front toe to be way off after only 5 months....one rear wheel also off some....tires refilled to 42 PSI (one with slow leak).

Scangauge showed a 3-4 mpg gain for a typical "trip" under similar conditions.

Will be redoing my alignment AT LEAST every 6 moths.

Seems all of the vehicles I've done an alignment on have been OFF by quite a bit.

[BHarvey]

Getting ready to get mine done when I get the tires swapped around.

[Gasoline Fumes]

Anybody have any good tips on DIY alignment? I need to check mine before putting the Blizzaks on. I haven't aligned it since replacing the front subframe this Spring. It can't be that bad, I've gotten my best MPG since then. But I should at least check it.

[user removed]

In most cases tire wear will give you a good indication of alignment issues. Toe can be set with a tape measure by measuring the difference between the same groove on the front and rear of the front tires. It should be close to no difference to slightly less in front versus rear. 0 toe will make your car not quite as stable in tracking, more prone to following grooves in pavement and slightly less directional stability, but it will help mileage some depending on how far off it was before the adjustment.

Another way to check is to wrap a string around all 4 tires and see is there is anything that seems to be off. This will require you to find out what the difference is between front and rear track, the difference between the width of the center of the front and rear tires, which on some cars can be significant.

Bottom line is most alignment issues will show up in tire wear, as additional rolling resistance due to scuffing of the tires will increase wear. Toe in will wear the outside of the front tires, while toe out will wear the inside and cause poor directional stability.

Most of the time front end alignments last a long time if they were correct in the first place. Most tires hold balance well after the first re balance at about 7k miles, in spite of what a dealer may recommend. I generally let Wal Mart rotate and balance my tires. They will re balance at no charge if you have vibration issues later.

regards
Mech

[NoD~]

Originally Posted by Gasoline Fumes

Anybody have any good tips on DIY alignment? I need to check mine before putting the Blizzaks on. I haven't aligned it since replacing the front subframe this Spring. It can't be that bad, I've gotten my best MPG since then. But I should at least check it.

I once swapped my entire suspension and didn't get aligned. In only a few short trips, I ruined some fairly new tires. I learned my lesson after this.

On my minivan, I needed new bushings. I installed them myself. I swapped my struts as well. I could visually see my alignment was off after that... given my bad experience in my Neon in the past, I decided to give the DIY route a try. I followed this method...

(Have a link, but can't post a link due to my low post count... Google "DIY Alignment - Part 1 - YouTube")

I'll type out the run down later if you want to know how it works in a written detail.

Since, I have not taken it to a shop to check the alignment. I can say, though, that it has had probably close to 20K miles and my tires are still in great shape! Wear is even, the van drives very straight, etc. I give that method my two thumbs up!

[some_other_dave]

The toe angle seems to be the biggest contributor to tire wear and to rolling resistance. (Both from scrubbing the tire against the pavement, I guess.) You can check the toe angle with strings and jack stands. You have to make sure the jack stands are the same distance from the centerline of the car, which is the hard part. (Sometimes just determining what the actual centerline is turns out to be the really hard part!)

After you get the stands set up and string tied to them so that the string is parallel to the centerline, you measure from the string to the rims. A measurement at the front-most part of the rim and the rear-most part of the rim will give you an idea if the wheel is pointing out at the front (toe out) or out at the rear (toe in) or if both measurements are equal, you have zero toe. In general, you want zero toe for lowest rolling resistance, and toe-in for stability. Or toe-out for instability, if you need your car to be unstable for some reason. (Say if you're autocrossing it.)

Whichever way you want to set the toe angles up, there are a few things to remember:
- We're talking small distances here. If the difference between the front and rear of the tire is more than bout 1/8", chances are that is too much toe angle on that wheel!!
- All suspensions have some compliance, and as a result the toe angles will change while you are driving. Driven wheels (front on a FWD car) will tend to pull themselves into more toe-in, while non-driven wheels will tend to get dragged into more toe-out. As the suspension compresses and rebounds, the toe will also change dynamically. (This is called "bump steer".) It may be necessary to compensate for those when setting the toe statically!
- After making changes to the suspension settings, it is a very very good idea to bounce the car up and down and roll it back and forth for everything to settle in. It is even better to drive it around for a little while, but that takes more time.

If you google "DIY alignment", you'll find a lot of information out there on this subject.

-soD

[RH77]

If you really want to do it right, insist on having the weight of the driver in the driver's seat (or sit in the vehicle during adjustment) and other significant weights added (such as proper fuel level and if you routinely carry cargo or passengers, have those at the proper spots). This compresses the suspension to perfect the numbers even more.

In the past, I had a shop perform an autocross-specific and the vehicle was really twitchy on the highway (thanks to Old Mech for the reminder) -- be forewarned that the 0 front toe will have the same effect. Since most of us here are pretty attentive drivers, it isn't critical, just pay extra attention. I pulled the power steering belt, so for me, twitchy is an understatement , but FE gains are worth it...

I seem to always have front tire wear on the inside, so there's a toe-out issue (perhaps required specs for the vehicle model). The plan is to go for zero.

By the way, how does camber factor into the equation? Some of us corner aggressively to maintain momentum, but the majority of time, EcoDrivers are moving in a relatively straight line...

It would be interesting if people could post their alignment "Printout Sheets" if the shop can provide you one -- and if you notice a difference or can log better FE...


RH77

[user removed]

Camber generally does not affect tire wear as long as it is not way off. Camber is how much the tires lean in or out compared to truly vertical. Racers like negative camber for handling.

Ever heard of negative camber in a solid rear axle rear wheel drive?

regards
Mech

[user removed]

Actually it was done in NASCAR, a cheater trick where they bent the axle housing in a press to give about 1-2 degrees. Not enough to make it come apart. I think it's against the rules when they found out it was being done.

With a 2+ foot long axle a misaligned bearing would just fail in short order.

regards
Mech

[some_other_dave]

When NASCAR changed from bias-ply tires to radials, they found they needed a lot more negative camber. So they'd bend the axles prior to installation, and those started failing. So the Powers That Be specified some amount of camber, and now that's what they all run.

I think some of the RWD live-axle cars do actually have some negative camber in back. But you can't really change it because it has to be designed into the housing.

Generally, negative camber will create a little bit of thrust to the inside, especially in the corners. It isn't much, but it will use a little tiny but of power. Again, not much compared to the scrub from having the toe angle messed up. Probably not worth worrying about.

I must say, I liked driving that one car with toe out in the back for a little while. It was really quite exciting!! Even more when it spun with little provocation and wiped out a wheel and one corner of the suspension--that was very exciting indeed!

-soD