VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 front end vibration

Hello -- I have a 1930 Chevrolet 1 1/2-ton truck that I drive occasionally, but only for two or three miles. It has new tires, tubes and flaps and it steers OK, but when I get it into third and fourth gear (which isn't fast at all) , there is a pronounced vibration in the front end. I don't know if one of the rims is bent, if the wheels need to be aligned, or what. There doesn't appear to be any way to balance the old split rims. Would a good alignment shop even know what to do? I'm going to park the truck because I don't want to cause damage. Thank you.

I would first check the tires to see if they might be out of round. Jack up a wheel and use a stationary reference point to check as the wheel is rotated. If that shows all is ok then check the toe-in. Caster and camber are much more difficult to adjust (by adding wedges or bending the axle) so are not the first things to check. A good front end shop can make adjustments if necessary.

Thanks, Chipper. I know the tires have much less air in them than the recommended 60 or 65 pounds, so that might be a contributor. I will fill them to see if that helps. I tried the "inner-outer" measurments to check toe-in, but the old split rims are uneven on the inside -- probably from being forced open and closed with a rim jack -- that I'm not sure how valuable the measurements really are. Any suggestions? Should I measure from the inside of the front tires instead?

To accurately check toe-in you will need to mark the tread (masking tape with verticle line) of each front tire. Lift the front axle so the tires are off the ground. Measure between the marks with both wheels pointing forward. Rotate each wheel back 180 degrees and measure again. The difference between the two measurements is the toe-in or toe-out.

If the rims are bent then the tires will wobble and at some speed cause the front end to also wobble. The amount will depend on how the bends line up. Each turn or deviation from straight ahead will change the orientation and therefore the intensity of the wobble.

Thanks for the tip on measuring the toe-in. That will be simpler, and more accurate, than the approach in the circa-1928 "fix your Chevy" book that I was referring to. Kevin

Probably the most acurate way to get the toe-in spot on,would be to measure from the insides of the front wheel felloes(where the spokes fit into,or your disc wheel felloes),this would give the most accurate toe-in reading,as you wouldn't have to worry about rims being out of true or tyres being out of true as well.
Once the toe-in is set(1/8"),then you can try to get your rims to run as true as it's possible to make truck rims run.I've been through the same hassles with my '28 truck,and everything is just fine now.The maximum castor angle unloaded should be no more than 2 - 2 1/2 degrees.
As for balancing the front wheels,if you can find a good front-end man/tyre shop,probably one that deals/works with trucks,you may be able to get the wheels balanced on your truck.My front wheels were done this way,and now there is no more shimmy or excessive vibration from the front end,even running along at 50-55 MPH.


:)