Need support. Just found out my radiator is leaking

[Doubeleive]

Have you checked drain petcock to make sure its tight and if is check Oring on petcock.

they deleted the drain on the gmt900's, unless you install a older model compatible radiator there isn't one.

 

[Rocket Man]

The new replacement OEM GMT 800 radiators don’t have petcocks either, they eliminated them also. I replaced the one in my 02 Yukon Denali a couple years ago and it came without one. My old one had it.