The Stovebolt Site Forums The Shop Area Driveline Front End Alignment on my 56 Chevy 3100

I am going to get my 56 aligned when i get new tires put on. I am curious what others have experienced when getting an old classic truck aligned, when it hasn't had any work on the chassis in like 40 years. I am hoping they don't throw any crazy things at me, saying it needs all new tie rods, etc. It drives good now, no major issues, but it does steer to the right a bit. The current tires are like from the mid 90's and are literally falling apart, so it was time for new tires! Thanks.
Gene

Be interested to see what folks have to say as my 56 3100 does need an alignment. The left front wheel has a visible positive camber.

Call in advance and tell them what you have.

There are as couple places here in Atlanta that will do antique cars but they need advanced notice to make sure the one guy they have who knows how to do it is available.

If your shop can't or won't do it, they might have someone they recommend.

Hi Gene,
There are only a few adjustments. First, the steering gear needs to be centered in its travel. You can do that yourself. We've discussed it here many times and we probably need to write up a tech tip about it. Second, the caster angle needs to be checked/verified. Somewhere between 2.5 and 3 degrees positive caster is what you want. If your springs are really old and if they've relaxed, it can affect caster but usually not too much. If you use larger tire diameter on the rear than the front it will reduce caster. A caster setting too low means your truck will steer easier but it will wander more easily too. Third, your toe-in setting is important. It ought to be something like 1/16" toward toe-in if all your front end parts are in good shape (and if they're not, I'd suggest fixing them). Worn out kingpins, tie rod ends and even your drag link can have an effect on your entire front end. Fortunately kingpins and bushings & bearings are available and not too expensive to replace. Also you can get new balls for your control arm and steering arm and that will help snug things. You can even get rebuilding kits for your tie rod ends and drag link, too. Unless you remove your front axle and have it re-bent you cannot adjust your camber. Only caster can be adjusted on a solid axle. Hope this helps.

Oh, one other thing. "Road crown" can cause a vehicle to pull while driving. Often people will try to compensate for this by adding positive caster to the left front wheel but please don't let anyone try to tell you that will help on your truck. They can add caster shims but all it will do is to cause the spring on that side to flex more when the spring to axle nuts are tightened. The axle is about as rigid as a railroad track and causing one side of it to bend by adding shims is folly.

The only thing you can adjust at most shops is the toe without changing parts.
The only parts they can change is caster with shims.

Any issues with camber (other than replacing worn kinpins/spindles) is a axle bend. And like otto said some rare shops have one guy that can do that.

Although you can sometimes find those guys at the big truck repair places as many big freight trucks still have straight axles. And a few of them know how to handle bending small truck ones as well.

its best to call the local restoration shops they usually know which alignment shops work on 50s vehicles

The "you can't adjust stovebolt alignment" advice you get from most people is a myth. I grew up around a shop in the 1950s where straight front axles were bent/twisted to adjust caster and camber on a daily basis. The only things missing in most alignment shops these days are the equipment and skills to do that. A simple piece of H beam, a 20 ton hydraulic bottle jack, and a couple of heavy chains are all that's needed to change camber. There's a couple of twisting fixtures that are needed to change the caster on one side only. Wedges between the axle and the front springs can be used to make the same caster change to both sides at once.

Tight, unworn wheel bearings, king pins, bushings, and tie rod ends, and a properly adjusted steering box are an absolute must before a good alignment can be done.
Jerry

One of the shops I referred to here in Atlanta won't even attempt to align an antique car if there is any undue play anywhere in the system. It couldn't be done accurately in the first place and he isn't going to risk his reputation trying to make it "ok".

Niobrarafun, what is the condition of your steering and suspension system? When I installed new wheels and tires on my truck I was going to have it aligned. As it turned out, all of the original, unrestored parts were in such good shape, no alignment was needed.

I can let go of the wheel at speed and it tracks smoothly and straight. 8000 miles later the tires are worn perfectly evenly from side to side. It's actually quite amazing. Maybe you'll have similar luck.

Hotrod how about a tech tip on how to bend that axle with some pictures. or a whole tech tip on all the adjustments. that way you can walk into a shop and say "do this"

Speaking of measuring. For you true alignment guys. where is the appropriate place to measure toe?

if you use just the wheel drum lets say and its 1/8th difference then the outside of the tires is going to be way more than a 1/8 if you used the out rim lips it will be less of a difference.
vs all the way out to end of tread tire center etc.

if you use the bar across tire method will you get a different measurement.

if you guys get what I am trying to say.

Talk about getting the "deer in the headlights" look if you do that.
Per the service manual, toe-in is measured from centerline of tire tread to centerline of tire thread, front and back.

For accuracy? The problem is you need a level measurement at the center of your wheels on the front and rear. Your oil pan and things like your drag link will get in the way. You can rig up a device easily using a hollow piece of small electrical conduit pipe or 1/2" PVC pipe with a bolt set into one end of it to allow accurate measurement of the front but you won't be able to get a 180 degree measurement front to back at the middle of the wheel and that's what you must have to be accurate.

The best way is to use the device which attaches to your wheel rim and uses a laser beam to project in front of you. Measuring from wheel to frame for the rear measurement doesn't work. Theoretically it will but if you're shooting for accuracy it won't get you there. You'll be dependent on too many variables.

Long years ago a friend built a device out of plywood that you drove onto and then manually pushed your car/truck until you centered both sides of the device with the center of the hub spindle...wheels pointing straight ahead. You used this to measure the distance to the outside of your wheels and it worked pretty well...for him, anyhow. He seemed to be the only one who could use it properly but it did work and was accurate. I remember he worked hard to make everything square and he braced it so it couldn't change.

We always used a spring loaded device with a sharp stylus to scribe a line on the centerline of the tire tread for toe measurements. It's a lot easier to see if you make a wide stripe on the tread with a piece of soft chalk first. The trick would be to find a shop willing to fabricate the specialty equipment needed to do axle bending- - - -something they might only get asked to do a few times a year. It's all done by "cold bending"- - - -no torch work involved at all! You're more likely to find people familiar with axle bending around a heavy truck (18 wheeler) shop, where straight axles are usually what's used on road tractors.
Jerry

"For accuracy? The problem is you need a level measurement at the center of your wheels on the front and rear. Your oil pan and things like your drag link will get in the way."

Jon, the tram bars we used for decades to measure toe back when lasers were the stuff of science fiction (Buck Rogers' ray gun, etc.) work just as well now as they did back then. They had a support bar that sat on the floor, and extendable measuring pointers that could be adjusted to spindle height. I've still got a whole system like that, including portable turn plates, magnetic caster/camber gauges, and a tram bar for toe measurements. All I need is a level shop floor. I think I gave something like $300.00 for the whole setup.
Jerry

Thanks guys for this wealth of knowledge. I am hoping to hear back from my local car club as to a good shop to take my truck to, to get this alignment done.
Gene 'NiobraraFun'