Battery ODYSSEY or OEM Mercedes

If willing to pay for a Optima yellow top, I suggest you get an Odyssey battery instead. It's a much better battery for about the same price.

I finally spent the money on an odyssey extreme on my 7.3 along with an aftermarket starter and battery cables. Absolute game changer in the wintertime. I could leave it out in the cold for a week and it would start faster than the old battery setup would in the summer.

I’ve ran odyssey in my RZRs and they always held up through abuse and neglect.

Buy an odyssey. It will pay itself off in the long run nor let you down. I just ordered one for my Rubicon.

I'm running a 320 amp alternator with AGM odyssey battery so far no issues

Commenting here for others to find. 5TA915105B has dimensions that align with Group 48/H6 specs. I bought an Odyssey 48-720 and it was a perfect fit. Bonus tip - FCP Euro has it for $250 and it includes their lifetime warranty.

This just happened to me last month on my 2017 C43 on the OEM battery. I guess five years is typical on these newer MB.

If the battery dropped to 9V it is probably defective.

Exactly the same issue I am currently facing with a month old GLC300. No resolution yet

Odyssey and wasn't a fan died quick