Originally Posted by Fly03Z06
With the C5's parasitic draw it is critical to how your electrical system and BCM will function BEFORE you ever turn the key. The C5's unloaded battery minimum is 12.5 volts at 500 CCA per Paul's tech video.
Required terminal torque is 11 FT. LBS.
Anything less.................you get BCM gemlins.
I've seen his videos.
The C5 draws less than 2 amperes during key-off periods (Just enough to maintain PC/system settings with theft deterent armed) and when its running, the alternator takes over at 13.78 to 14.4 volts and up to 125 available amperes.
As most know, a batterys CA and CCA only applies to how many peak amperes the starter will draw during starting depending on tempurature. The Red Optima group 78 produces 800 CCA and 1000 CA at 12.8 volts fully charged which far exceeds the factory requirements for the GM C5 that came stock with a 75.
In other words, RC really makes very little to no difference (Maybe .3 of a volt), unless you want longer life out of a battery for lighting, accesories or your stereo with the key off.
I've never thrown BCM codes. EVER. I check my PC every spring. The only history code I've ever noticed is P1416 AIR System bank 2 back in 2008 which cleared on its own. I didn't even throw any codes during the battery change because I left the battery maintainer hooked up. No idle learn procedure, no FOB reprogram, no clock reset or unlock, nothing. More than enough voltage and current to maintain memory.
Pauls "Tech" video primarily refers to the Column Lock issue which from what I heard by the dealer required too high a voltage to disengage the lock (hence the recall for the bypass) because GM knew it was cheaper to perform a simple bypass of of the column lock than it was to replace every battery in every C5. They also realized that no matter how good or big a 12 volt battery is, it will always drop below 12 nominal volts within a week without a charge because of the system draw you refered to.
He also NEVER mentions the vehicle's battery being maintained by a maintainer. Parasitic draw becomes a non-issue with a clean 3 ampere battery maintainer providing 14.4 to 14.7 peak volts continously to the battery and system.
There's just not enough evidence in his video to support going out and buying a battery with 120 RC.