Any 4wheel Alignment Guys Here?

WIfes 05 Uplander started pulling to one side. Had the tires rotated with the oil change, and had it aligned. Still pulls to the right bad, but let front tire is wearing on the outside very bad, and very fast. Counter guy showed me the print out of how ad it was out, which it wasn't out bad at all, but why would it pull still pull to the right, but eat up the tire on the left? I don't think its my alignment guy, hes been doing them for me for over 20 years.

Alignment can be a real can of worms. First, let me say that many of the newer vehicles have settings that are NOT adjustable. Manufacturer will say that if a particular non-adjustable setting is out of spec, it is because of bent or worn parts.

Now, to get to the REAL issue.....the following settings have the following effects....

Caster. This is one that can cause hard steering, slow return to center, or pulling to one side or the other. Will NOT cause tire wear. Caster should be within 1 degree of the same from side to side, with 1/2 or less preferred.

Camber. This setting is how straight up and down the tire is in relation to vertical. In at the top is positive camber, out at the top is negative camber. Camber is generally within a degree of ZERO. Variation from side to side is allowable up to 1 degree. Camber can cause pulling or drifting to one side or the other. Also, camber can cause uneven tire wear. Many times, camber is adjusted to counter the effects of road crown.

Toe-in or toe-out. A VERY important adjustment. Needs to be set as closely as possible to factory recommendations. Can cause rapid, excessive tire wear. Typical tire wear patters is "bars" across and diagonal to tread.

The problem you describe can be caused by a number of things. Without looking at the numbers, I could not venture a guess.......

Toe in is important because it shows initially as wear to the edges of the tire(s). If toe is not centered on the steering rack or gear, it can cause excessive wandering and imprecise steering.

Camber will generally pull to the positive side, though not usually a strong pull.

Another factor is if an alignment was done on just the front end or on ALL FOUR!!! On a rear wheel drive vehicle with non-adjustable rear, a thrust line alignment is recommended. This trues up the front end to the actual tracking of the vehicle. Id the rear is adjustable, then you should only do a 4-wheel alignment. Doing otherwise is just throwing money and time away.

One other thing that can be a factor is simply a bad tire. In this day of radial tires, the general thinking is to maintain the direction of rotation of the tires. This means that rotation amounts to moving the fronts to the rear, and the rears to the front. If a tire is causing a pull, this will not generally remedy the problem.

This is about all I can offer without seeing some numbers........

Informative post.. Thanks

Rotate the tires right to left, that is the first thing to do when fixing a pull. Tire pull can be a sign of a separating tire, or could be nothing but a tire pull. I have seen new tire pull,rotate them side to side and never have a pull again.
(Camber is +out at the top)

Not to beat you up on your post as I"m sure you know what you are talking about BUT you are wrong on camber. Pos. Camber is out on top & Neg. Camber is in on top.

that is correct on the camber.
now my turn on the caster... caster is adjusted to compensate for pulling, not camber. such as for the road crown.

You are correct. I always tried to set the left side Caster 0 - 1/2 more positive on the left compared to the right to compensate for road crown.

The answers below are helpful, but if you have a tire wearing fast, it's either loose parts, or severe tow-in. Camber will cause tire wear (and affects pull more than other settings), but will not cause rapid tire wear. Your shop should closely check your suspension for wear, and if it's tight, the only answer is an alignment problem. Your alignment guy may be an expert, but his equipment may be letting him down. To rule out tires, it would be best to find a shop with a Hunter Road Force balancer, which will measure rolling resistance and run-out of your tires and wheels. I happen to be a manufacturer's rep for Hunter, and we market the only balancer with this capability. Most new car dealerships have one, as well as our alignment equipment. There is a possibility of a brake caliper not releasing properly and causing your pull, but you would probably smell the pads getting hot if this were the case.

LEt me add this, a 4 wheel alignment was performed on t his van. My guy has always checked for worn parts before, and during, the alignments hes done for me in the past. Hes done some 30 or more alignments for me over the years, and 3 or 4 different machines the owner has bought or him over the years. Each machine was "better" than the one it replaced. I have never had a problem with them, or the company he works for until they decided to start closing on Saturdays. (KInda makes for a goofy week for me!) The tires are only a couple of years old, and have maybe 20000 miles on them, we just don't drive this van that much,ut the last 200 - 300 miles have really ate up the outside on the drivers front tire so bad, Im scared to drive the thing. Anyways, I plan on rotating the tires around, just to fell better about getting it somewhere to get a second opinion on the problem. THanks for your input!

Anybody on your side of the Enoree River that does a good alignment??

OK, here goes; I"m sure I"m going to open a can of worms here but I"ve learned a few things from 20 years in the alignment business. Many suggestions here are good and easy to try like rotating tires left to right. Also it is correct that many vehicles no longer have usable forms of camber or caster adjustment. Ackerman compensation has been designed out of most cars and trucks that I know of and tires scuff like crazy in turns now. That said, I don"t know what kinds of roads are in different parts of the country but IMO I would say that you would have to be driving on top of a pipe to need camber adjusted for "road crown". Serious wear on one side sounds like some kind of damage issue. Also don"t forget that things like a slightly dragging brake caliper can cause lots of pull to one side. You seem to like your technician but I have to say that I"ve seen very few shops that "really" understand alignment (particularly these days where few things are adjustable so there is nothing to learn).

Of the two really good ones I knew, one died when a customer was driving on the rack and hit the gas, as he was guiding her from the front. The other one had to retire for health reasons. I need to find a good shop, My dually eats tires.

anyone could forget to tighten a bolt or strip it enough to give later, have seen last one before

I doubt it's an alignment issue now if it shows correct. Tires take a "set" and once started down that path there is nothing you can do except replace the tires. I've had this problem on my truck several times and have tried everything to stop the wear. There is nothing you can do for those tires. Just run them off and get new ones when they are shot. I would bet with different tires it will run straight and true.

Does the wheel turn free? Brake caliper could be holding and making it pull to one side. That would explain pullin to one side after rotation.

Better check your memory on the cross caster. To compensate for road crown the right would be slightly more positive than the left. (left would be driver's side on most vehicles in North America.)

Dick W
You are correct. Right need to be more Pos. than the left. I wasn't thinking clearly.

More caster will help turn shorter at low speeds (think 4450 FWA axle vs 7250 FWA axle) and return to center at higher speeds. Less can cause a dead feel on center.

I have run across quite a few new truck tires that will pull. If the OD of one edge of the tire is a bit larger than the edge the tire will always turn away from the larger diameter.

I had a set of Chinese tires that started pulling to the right so bad a front end alignment couldn't straighten them out. I probably could have gotten 10k more miles out of them, but couldn't stand driving the truck so I replaced them with non Chinese made tires.