Refrigerant 134a or 1234yf??

[UrbanRage]

I have a 2017 GMC Sierra with the 5.3l. Last week, I noticed that the A/C was blowing cool but not cold air. When I was making the appointment with the dealership, the service rep asked if I knew which refrigerant my truck has because that would affect the cost by several hundreds. My immediate question was, "How can I find out which one is in my truck?" Her reply was that we wouldn't know until the truck was in the shop. 

 

I didn't see an A/C system name plate under the hood. Is there another way to know if I have 134a or 1234yf refrigerant?

[CamGTP]

The factory sticker is on the plastic cover over the core support directly behind the grill, basically right in front of your face when you open the hood.

 

I got $1 on it being 1234yf, my 2016 is still R134a.

[UrbanRage]

Holy ******... I can't believe that I missed the large black sticker with the snowflake on it. 

 

I'd send you the $1, but since it is 1234yf, I'm going to need every dollar for the repair..  

[David279]

Thanks for this I was wondering the same , gonna need every dollar for this too