[NoMoGMPG]

Never mix battery types, stay red-red, yellow-yellow. They have different characteristics between them and will work against each other in chemistry ways. Got this from an Optima dealer.

Also, getting back to the post topic, ACDelco has for a LOOOONG time had a problem with leaking batteries at the positive terminal and it is WELL documented. If the vehicle is under GM or GMPP warranty, all subsequent damage from the leaking battery should be repaired either no charge or with the extended warranty deductible. Press the issue with the service manager, tell him/her that you KNOW their batteries have this issue and that you know that THEY know. I can't recount how many batteries, cables, and starters our dealership has replaced because of this issue.

The problem with the ACDelco batteries are that the engineers had the post retaineg plate inside the battery changed to a PLASTIC part, which will break and leak upon overtightening. Since the standard for tightening a battery bolt is S-N-U-G, this will crack or break the PLASTIC retainer.

Feed this to the service manager and he will cower at your intimate knowledge resulting in capitulation to you.

Dave