Radiator Cap Question

[Corey'sgotachev]

I have a noob question. I've noticed the coolant level seems to be 2" low all the time. Last time I filled it up, I started truck (350) and waited. The overflow tube had coolant coming out of it but only until the motor is actually warmed up. The coolant stopped coming out then and temp seems fine driving around town.

I want to drive truck to work once in awhile 50 miles one way. Don't want to run it low on coolant.

What cap should I get so that coolant doesn't leak out? Don't think recovery tank was stock. Any recommendations?

Thanks!!! Happy New Year!