DO-IT-YOURSELF WHEEL ALIGNMENT

Isn't it worth the $50 to get the local shop to get it exactly right...?

Go out and get a second job for one day. Take the money that you make on that one day and get an alignment done at a shop. There....that's the best info you will get. Anyone who tells you to go get a tape measure or any other sort of half assed measuring tools is just wasting your time.

Ian

Someone posted recently that alignment could in fact be done reasonably accurately with simple tools.

I wouldn't want to risk a set of good tires, and possibly my life, on anything but the best, but to understand how such a simple alignment process could work would be interesting and edifying.

"Syl" wrote in news:fR_We.4549$6Z1.1190137 @news20.bellglobal.com:

as stated, a tape measure will give a fair estimate on toe-in....ask friends and family for insight on GOOD align. shop or ask shops in town that dont have a front end machine who they TRUST (they have to get there aligns. somewhere after parts replacements and then they have to stand behind the job).....as far as quicky algn shops (sears, firestone, etc.) from what ive seen most of there techs should be flipping burgers..........IMHO, kjun

Actually, with a good tape measure, some jack stands, conduit, fine string, turn plates, a calculator, a good understanding of how front and rear end geometry works, and half a day he could do a pretty good alignment. It wuold be a better use of his time to pay a pro to align it, though.

JazzMan

snipped-for-privacy@nospam.nix wrote:

Basically you need to set up references to the car, I use two exactly parallel strings, one on either side of the car, strung tightly between two pieces of conduit, one at each end of the car, set at axle centerline height on four jackstands. Meauring from the string to the centerline of the car or centerline of the front and rear suspensions, I get the strings perfectly parallel to each other and with the car centered between them.

Beforehand, I jack up each wheel individually, keeping the weight of the car on the suspension, and spin the wheel, using chalk against the center of the tread to make a mark around 1/4" wide all the way around the circumference of the tire. Then, I use a scribe resting against a jackstand to make a very thin line in the middle of the chalk by spinning the wheel again. To test that the scribe line is planar, I spin the wheel yet again and observe the mark in reference to a fixed object placed adjacent to the tire tread. If the mark wavers or moves at all then I rechalk and rescribe. With practice I get it the first time nine out of ten times. The human eye is capable of seeing one thousandth's of an inch movement relative to another non-moving object, that's close enough for an alignment.

Next, I jounce the suspension while rolling the car forward and backward. This settles out the suspension. From there, taking measurements for toe to the scribe marks is easy, with a tape measure marked in 16ths you can easily get 1/32" resolution by interpolating. To check camber I use a cheapie camber guage from Sears that I calibrated against a known perfectly vertical surface. Now, the cheap guages are only marked in whole degrees, and with interpolation about the best to expect is 1/2 degrees, but for the cars I drive that have a tolerance band one degree wide this is perfectly fine.

Checking castor is a bit more complex, you'll need turn or swivel plates because what you do is measure the camber change as the wheel is turned and then calculate the castor from that. For turn plates I use two pieces of 1/4" steel 12" on a side for each wheel, with grease between the two plates. This allows the top plate to slide/rotate against the bottom plate fairly easily. I used a protractor to verify that I turn the wheels the same degrees relative to the centerline of the car in each direction, generally 20° each way from straight ahead. You'll find the formula on this page:

There's nothing inherently better with a machine alignment over doing it yourself. What the machines do is to allow a technician to align many cars in one day, very quickly, do all the calculations automatically with no risk of calculation error, and be able to automatically print out before and after spec sheets. The machines are wonderful for increasing productivity in the shop, but alignments were being done long before computers ever existed. A DIY alignment can be just as good for the tires and handling of a car as a machine alignment, but it will take many hours to do and every step should be double checked to reduce the chance of error. The reason I do my own is because it's a learning experience, I can do it when I have time rather than rearranging my schedule to fit a shop's hours of business, and because I enjoy working on my car.

JazzMan

Rant follows: In 25 years in Houston I have yet to find a shop that has techs that are capable of doing an alignment or will take the time to do it correctly. I put front struts on earlier this year, took my car to a supposedly good alignment shop and it comes back with neg camber on the left and pos camber on the right. I could stand back from the car and see the problem without aid of machines. I ended up re-doing the alignment myself in the driveway. $75 wasted... again.

There used to be a really good frame shop out on Wallisville Road that could align just about anything. They had machines big enough to straighten 18 wheelers, trailers, etc. Virgil was one of the better mechanics.

Don't know if they are still there, but will have a look at the phone book in case you might need them in the future.

Were not expensive either.

Rant, I couldnt find them in the online phone book. Next time I pop down to Houston I may go by there and see if they are still in business. IMHO, they were some of the best.

Going east on Wallisville Road, you turned left on the first road past the landfill, and the shop was a block or two on the right.

Great! Thank you for the info. Where are you located? I am off I-10 Fry/Mason in Katy, work in the Heights.

You're implying that there's a competent shop nearby.

I remember arguing with a local shop regarding my '56 Golden Hawk; the mechanic stated that he couldn't adjust the caster because his alignment rack said that a '56 Studebaker had non-adjustable caster, despite the fact that I had a copy of the appropriate section of the shop manual sitting on the front seat of the car with specs and adjustment procedures. Needless to say, when I got my '55 coupe done, I went to a tire shop with an "old car guy" behind the counter. (now there were issues with that as well, but not due to the mechanic... long story...)

nate

If there is one ... Sometimes I'm on (not 'in' because it's a bunch of islands) The Philippines, and there in the middle of nowhere there's nobody to align my truck, let alone the automatic tools to do it.

shakiro

There WAS a really good shop in Houston, and I hope it is still there. I'll look the next time I drive down (within the next couple of weeks, most likely).

I know what you mean,Shakiro.. Had a grass hut 4 wheel align my Passat in the nether parts of Brasil, with string, etc. It worked okay.

By the way, by daugher in law is from Cavite (or Cabite).. Are you near there?

Where are you located? I am off I-10 Fry/Mason in Katy, work in the Heights.¨

At one time, I lived in the Sheldon area. Most recently I commuted to Houston and lived off Westheimer near Beltway 8. I retired last October and live near Nacogdoches, but still come down occasionally for business, consulting, or just for the wife and I to have a little R&R.

Where in Brasil? Fala portugues?

Sounds familiar, at the mo I'm in Europe though. Cavite (they pronounce the 'v' as a 'b' because of the Spanish occupation of some hundreds of years) sounds familiar, but when I'm there, I'm on Mindanao, and Cavite is on the other big island, Luzon, near Manilla and Quezon City.

shakiro

Eu morei no Salvador, Bahia ao norte de Rio de Janeiro. Falo, mas faz muito tempo, e tenho esquecido muito.

Ah! Muito legal amigo! Gostei muito de Salvador, Pelourinho e tal :) E o que eh que a bahiana tem?

grande abraco,

shakiro