Battery Deka or OEM Volkswagen

Change it when it can no longer meat a battery test to spec, which has good margin before it starts causing issues, like freaked out ECU or hard starting.

I currently run a Deka Intimidator in my rig and it's been problem free for 3 years now

OEM VW Battery lasted 7/8 years, despite me nuking it by foolishly leaving my lights on. Sad day.

I replaced the battery of my 18 SE this year and did not code the battery. I replaced it with an OEM one from VW’s parts department and had no issues

Had my '18 R since May '18 and still on original battery, 25 mile commute to work each way about 1/2 hwy . At 57,000 miles.

OEM battery in my 2016 Jetta with 215k miles is still going strong.

In Mar 2022 I went to the dealer and got a new VW battery for my GTI $151. Not knowing any better, I simply swapped it in the parking lot - I did use a OBD-II device to keep circuits alive while the battery was disconnected. All worked like it should.

Deka ETX15, Deka makes a great battery and they’re sold under a few manufacturers.

Mine crapped out at 34 months. I bought a new one from VW since they had a 5-year warranty on it and it's still going...

I've got an essentially new Golf R only about 3 months old and I think my battery is no good. I keep it connected to a battery tender as I dont'drive it often. Even after a week of being connected it never reaches full charge. Also, After I discomnect I put a quick load on it by turning on the lights in order to remove the surface charge from the battery tendder. Prior to putting the load on and just after disconnecting the battery tender the rading is 12.8Votls. After putting the load on by turning on the lights for a minute the voltage reading then drops to 12.28 which seems awfully load. I'm assuming my battery is no good.