Battery: Tried AGM, back to old tech

Based on my experience with Optima batteries in other cars, I thought AGM was the way to go for car batteries. AGM is completely sealed, zero maintenance, and does not cause bad terminal corrosion.

I did not try to fit an Optima in the Jetta. Instead, I bought the exact fit made by East Penn (DEKA) from Carquest. Carquest puts their name on it.

The first AGM quit within two years. The battery formed a bubble and pushed the + post up an inch or so. I got it replaced with the same model. The replacement lasted three years, but only because I started trickle-charging it manually overnight about once per week. It had been weakening for the past year, and it got to the point where the cranking was so slow, the sound would turn the heads of passers by.

Now I have the next-best, non-AGM model. We'll see how that holds up. For now, it is amazing how much difference a strong battery makes!

aj164 said:

Based on my experience with Optima batteries in other cars, I thought AGM was the way to go for car batteries. AGM is completely sealed, zero maintenance, and does not cause bad terminal corrosion.

I did not try to fit an Optima in the Jetta. Instead, I bought the exact fit made by East Penn (DEKA) from Carquest. Carquest puts their name on it.

The first AGM quit within two years. The battery formed a bubble and pushed the + post up an inch or so. I got it replaced with the same model. The replacement lasted three years, but only because I started trickle-charging it manually overnight about once per week. It had been weakening for the past year, and it got to the point where the cranking was so slow, the sound would turn the heads of passers by.

Now I have the next-best, non-AGM model. We'll see how that holds up. For now, it is amazing how much difference a strong battery makes!

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You could have save time and money if you had just had a dealer look up your car by VIN and bought that battery. The correct battery for your TDI at a competitive price.

There is a very good chance that non AGM battery you bought is rated for a gasser. Some of your parts house listing don't even show a different battery for a TDI than for a gasser.

From what I have heard from some post here, AGM's don't work well in a TDI.

I found the battery thread

I know this is a zombi thread, but if you'd gone with an Odyssey or a Johnson Controls/Interstate you would not have had a problem. I have an Odyssey in highly modified Mustang that is only occasionally driven and it's been in the car for 12 years. When it's sitting up I have an Odyssey computerized charger on it. That battery even 12 years old spins that 400+ HP 302 so fast it almost doesn't have the typical Ford sound.

Speaking of Zombie thread...

I have not been happy with the AGM batteries. The first one lasted less than 3 years, the second one lasted 7 months.