Chevrolet Repair: ac conversion, ac conversion, oil additives

Question
conversion kits to 134 are available, some of which contain additive to eliminate necessity of vacuuming out the old oil, some with just 134 and no additive or advice to vacuum the old r12 oil and refrigerant.  What is the downside to just adding 134.  Are the oil additives worth bothering with?  thanks

Answer
Hi Clem, I would buy  the kit that comes with the pag or other type of oil. You need to install a oil  that the R134a will pick up and move around the system. This oil will stay on top of the old r12 oil. I have done many with zero problems, drain the system of freon,add new oil,e-vac and  recharge with r134a.

Hope this helps
Have a Great Day              Mark