So, I've had my '03 4Runner 4WD for almost 20 months w/ 32k miles. I've done the oil changes and irregularly rotated and balanced the tires.
Should I have the wheels aligned ? I feel no physical reason to do it (the truck tracks straight) I get a little shimmy every now and then on the interstate... Should a wheel alignment be a routine task ?

 

Unless you have lifted it or wheeled it hard its probably ok. I would have it checked when your put your first set of new tires on. The tire stores here will check it for free, you only pay if they have to adjust it. Ask for a print out when they check it and it will tell you what's in or out of spec.

The toe is the biggest one for tire wear and pulling and camber seems to effect the handling the most. I don't know what caster does, I don't think caster even has an adjustment on our trucks but they always print it out.

 

Increasing caster will increase the front wheels' tendency to self-center. Picture a bicycle front fork - notice the angle of the forks - it they were straight up and down the bike would be very hard to steer straight. Increasing caster increases the tire rolling up on it's shoulders when not straight ahead - this is precisely where the self-centering in yoiur steering comes from - the weight of the car keeps the tires pointing straight ahead since they have to lift the weight of the car to roll up onto their sidewall. Too much will increase tire wear and accentuate tire balance issues. Too little and steering is exhausting as it just will not track straight. Caster is adjusted on IFS by moving one upper or one lower (or a combination) pivot point. I.e. rotating the upper forward cam outward would increase caster. Or, rotating the lower rearward cam outward would also increase caster. On a solid axle rig you really can't adjust caster without moving the spring perches. It's the least critical alignment parameter though, so not much of an issue with solid axles as long as its in the ball park. Toe and camber specs are pretty critical, and need to be very close to spec. (I'd say plus/minus 1/4" on camber and 1/16" on toe.)

 

Thank's Flame, that's a great description. But, I don't think I have a upper cam. Did the IFS come with one stock? I now have Superlift UCAs.

 

This is a good basic primer: http://www.familycar.com/alignment.htm

Has to be some way to align it...

On my 90, the upper suspension arm has two bushings, and the lower arm has two bushings, at the pivots. These all have adjustment cams. (Maybe I better say: Both lower ones and the front upper one do for sure, I was just looking at them last night thinking about how tough it might be to take the arms off and put in poly bushings...) You 93 should be identical.

 

Oh so you have cams on the UCAs huh. Superlift didn't bother designing those into my kit. I've replaced all my UCA bushings and there is no cam on these, here's a pic http://community.webshots.com/photo/...51046126LQPbZF

 

Lucky for me the caster is always within spec anyway. And both sides are pretty close on caster, the tech said that is the main thing with caster.

 

Amazing they didn't include that. With my lift there would have been no way to get the Camber right if both the top and bottom couldn't have been adjusted to do it. It was Waay out! Plus the bushings are pretty shot - all squished to one side - and that probably doesn't help one bit...

 

I guess their tolerances were pretty good cause I never had a problem getting a good alignment. Except for when the UCA bushings were shot.

 

Anyway, to get back on the main subject. A wheel alignment check should be a routine task if you have a lot of $$$$$ invested in tires and especially if you have a tread wear warranty. Wear do to alignment problems are not covered by most tread wear warranties. I got 50,000 miles on my first set of BFG mud-t because I kept them aligned and balanced.

 

If you drive a domestic, I'd say about every 30k miles. But my Toyotas don't seem to go out of alignment anywhere NEAR as much as the domestics I've owned. I've been using this as a rule of thumb:

Align when you put new tires on or if you begin to see or feel signs that your alignment is out, whichever comes first. It's worked for me for over 750,000 cumulative Toyota miles. I often would go 60k on a set of tires without any unusual wear.

 

Heck my tires look as new as they did when I picked up the truck... It's so nice, I was changing two tires a year on my 300Z and I did all the proper align and bal stuff.

 

My Toyota dealer performed a 'free' four wheel alignment check for me as part of the 15K and 30K service. Even gave me a purty color printout with graphs, lines and x, y points.

 

JGAGE: what is up with your avatar? Is that a Hamas or Qaeda figure of some kind?

 

Yeah really, no wonder they won't do a free alignment check for you with that scary Qaeda hood on. Try dancing around like Sac State and maybe then they will do a free check for you.

 

I always take advantage of the free first wheel alignment and tire balance offered by Toyota (described in the Warranty Guide).

I'm back to the dealership within the first week of delivery with the following description that never fails to produce the alignment: "Steering wanders at a continuous high speed on a flat, level, dry road." That's what they need to hear from you to authorize the warranty adjustment. They'll also be too lazy to take your truck out on the freeway at high speed to try and reproduce the complaint.

This is also the time to request any custom alignment settings. My dealer will comply, but if my request is out of factory spec (as happens with my sporty cars and custom camber and toe specs), they'll have me sign a waiver before starting repair.

When I check the alignment sheets pre and post, it usually shows that those corners of the vehicle that were lashed down to the ship/train/truck (tow hook equipped) are those that required adjusting. And, the rig will often track better and become easier to drive at high speeds.

After that, if I keep them long enough, I'll get an alignment either every Spring or whenever the tires or any suspension components are changed.

 

Great 2 cents! Ok, I've got to know what are your custom alignment settings for your truck? What is the best camber and toe (for an IFS) for handling at highway speeds and optimum tire longevity?

 

The 'down by the river in a van' dance hypnotizes them into submission.

 

I had a 4th Gen V-8. I don't recall the settings and the records went with the truck when I sold it. I talked with the dealership SM about what I wanted (moderate speed on-pavement response, priority to quicker turn-in) and I think we compromised at 0 toe (I wanted toe-in, he wanted toe-out) and I don't remember camber. He had to stay withing factory range for the air suspension and X-REAS benefit to work right. It helped, and made the most of the otherwise useless Dunlops. I don't usually align to tire longevity, but go for best grip as priority with mileage trade offs.

As for other cars, too many variables to list so it comes down to "it depends."

 

Picture from when the U.S. went into Liberia, it isn't me.