In my 63 valiant I have a vibration between 20 to 35 mph after 35 it smooths out and rides like a new car I have new tires all the way around with the old steel rims. can't seem to find the problem with it jacked up it doesn't have the shake please help

The first thing to do is check the wheels for runout; a bent or misassembled wheel will cause all kinds of grief. Also check the tire/wheel assembly for roundness. If any are found seriously out of round the problem can sometimes be corrected by breaking the tire from the rim and turning it a half turn. After that have the tires and wheels professionally balanced. Then check all your front end components but especially idler arm, pitman arm, and tie rod ends. Probably 90% of the time these issues are caused by tire/wheel issues. It can be caused by incorrect caster but that would be the last thing I would check, mainly because it is relatively rare and it costs more to check/correct than other more likely causes.

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

One other thing, since you have new tires, it's possible that one is not seated properly to the rim. The only way to correct that is to break the tire down form the wheel and lubricate it with tire lube then reinflate. It might correct itself with time but there's no guarantee.

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

Very often, this kind of shake on a pre-'66 Mopar means the front ball-and-trunnion universal joint is worn and in need of overhaul or retrofitment. See here for rebuild parts info, and the cross-and-roller conversion info here.

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