Tire Pressure for Car Frame Alignment

Video Transcript

"DOUG JENKINS: Hi, I'm Doug. I work with twenty great guys in St. Louis at Doug Jenkins Custom Hot Rods, and we're going to do some work for you today on Expert Village. So step number 1 in measuring the frame on this nice old Packard is Ralph's going to get the tire pressure the same in al 4 tires, in order to, you know, if you have one tire that's flat, the car's going to sit different than if they were all at the same pressure. Ralph's going to put the tire pressure at 30 pounds, that's an acceptable figure. It's not important at this point that it'd be set for the road, but 30 works for the road, he's just making sure they're all exactly the same. I guess I should be clear about the tire pressure issue. The old tires like this, these are reproduction tires. The manufacturer is pretty wise, they didn't put any air pressure data on them. With your modern car, there'll be a maximum pressure on the tire printed. There'll also be a sticker usually on the inside of one of the door jams or in the glove box that tells you what the manufacturer of the car recommends for tire pressure. So these old cars, they don't have anything written on the tires and they don't have any stickers on the doors. A good rule of thumb, you know, a normal tire like this is somewhere between 28 and 40 pounds, and I'm embarrassed to say that we mostly go by appearance. Some tires, they just look overinflated when you put a bunch in 'em, some we run real high pressures in 'em. I don't know enough about the tire manufacturing technology to tell you, but there you go, that looks about right to me."