If you're finding water inside the cab of your 2019-2027 Ram 1500 truck (without backup/cargo camera), it can be a deteriorated third brake light gasket letting water in.
Replace it with this gasket that will not shrink or take a set like the cheap factory PVC foam gasket. This automotive spec foam rubber gasket is .187" thick and has an adhesive backing to attach the light.

APPLICATIONS: 2019-2027 Ram 1500 DT Series trucks that did NOT come with a factory cargo/backup camera.

NOTE: It is not a fun job, but it is necessary for the old gasket be removed and cleaned off the third brake light for a good seal.

RAM1924BL01

Geno's Garage

GASKET - THIRD BRAKE LIGHT ('19-'27 1500 DT SERIES, W/O FACTORY CARGO/BACKUP CAMERA)