ac adapter
 

I have a manifold with gauges for r-134 refrigerant with 1/4" hoses on them. The same size used on everything but cars. Does anyone know what kind of adapter or fitting I need to screw these hoses onto the car's air conditioning system. I'm wanting to check 98 and newer gm cars/trucks.

Re: ac adapter
 

I think you will need something like this:

Amazon.com: Mountain 8201 R-12 to R-134a...
Try you local parts store, they should be able to get you something like this if they already don't have it. I picked up a set from a local wholesale store for $30 about 4 years ago.