So my 2004 CTS-V #7 piston melted...I pulled it apart and went ahead and ordered a stock piston to learn that the original piston was a pressed fit into the connecting rod and the one I ordered has a full floating wrist pin. So I went ahead and ordered a new connecting rod for a 2004 CTS-V and it came designed to fit with a full floating wrist pin. The only problem is the new designed piston and rod weighs more.

OLD PISTON 606 GRAMS
OLD ROD 619 GRAMS
NEW PISTON 594 GRAMS
NEW ROD 645 GRAMS
NEW PISTON& ROD 1239 GRAMS
OLD PISTON &ROD 1225 GRAMS

Making a difference of 14 grams...will that cause a problem?

 

More than likely yes, I'd get it balanced...any time you change s part in your rotating assembly you should balance it.