Coolant leak

[David Haviland]

I have a 2013 Sierra 3500 6.6L that is leaking coolant but only after about 1 - 1 1/2 hrs of the engine running.  I can’t see where it’s coming from but it drips down from the front passenger side bumper area.  Thanks y’all.  

[swathdiver]

Probably a leak at or near the tank.  Time for a new radiator probably.

[Grumpy Bear]

Amazon.com: ACDelco 1149328 GM Original Equipment 10-5046 Dex-Cool Leak Detection Tracer Dye - 1 oz : Automotive

[Niners 365]

 I would say check you hose connections at radiator. Alot of those rust out right there and is hard to notice. So I agree with the "Time to replace radiator" due to location your describing. But b4 you spend the time and money, your sure it's radiator fluid?

  I only ask because you stated only after an hour n half. The natural evaporation from condenser happens then. And it flows on passenger side rail, that can flow to bumper. This happens after shut down of engine, and at idle.