Re: Steel Rim Design

Posted by Don Shields On 2015/6/16 0:04:15

As a 1948 model the car should have inner tubes to hold the air and the rim design should be irrelevant. Packard did pioneer tubeless tires and rims as standard equipment, but that came about in 1954, six years after your car was built. If you're running tubeless tires on 1948 rims, leaks could occur where the wheel hub is riveted to the rim. I've seen leaking modern spoked alloy rims sealed with what looked and felt like clear RTV silicone sealant. Another area that could be suspect is around the valve stem hole in the rim. On rims designed for tubes, that hole can be where the rim curves inwards to form the drop center part of the rim. That could make it difficult for the tubeless stems with their relatively thick and wide inner flanges to seal against a surface with that much curvature. As Packard V8 states, your best bet is to water test the tire and rim to see just what's leaking.

As far as what size inner tube to buy, any tire supplier should be able to provide the correct inner tube once they know the size of your tires.