My Costco Kirkland batteries finally petered out after eight years not to mention that they were starting to bulge a bit.
I went to CostCo but they no longer carry golf cart batteries, at least not in the three Monterrey stores. Sam's didn't either. I went to Battery Master and they carry the Trojan brand but sell for 4800 pesos each.
I was about to give up and checked online for an LTH battery center not to be confused with a franchise store. I found one in Monterrey and they had them for 2550 pesos each. I left a 500 peso deposit for each battery and upon returning the old Kirkland they gave me the deposit back (required by law, kind of like an excise tax). Because I went to them instead of them coming to me, I got an additional 10% discount.
We just returned from a one-month trip to Valle de Juarez, Mazamitla, Ajijic/Chapala, Ixtlahuacán, San Juan de Los Lagos, Matehuala and Montemorelos and they performed beautifully.
Now at home, and after two rainy and cloudy days, they are still sitting at 12.9.
Just thought I'd pass this on to anyone who wants to replace batteries here in Mexico. I can provide more info if needed.
BTW, these LTH batteries are made by Johnson Controls whose home office is here in Monterrey.