Wife has a 2013 250ISC. As a precaution I replace the car battery every three years. Two months ago I swapped the old Exide Sprinter for a new Optima Red Top Group 34. She only uses the car sporadically. The Optima will not start the car after about two weeks, and tests at 12.2V at that point, but a load test says the battery is in the good zone after it is charged back up using an Optima charger. Fully charged the battery is 12.56V (Fluke multimeter). Then just sitting it loses about 0.04V every day. Is a Red Top the wrong battery selection? I put an Optima Yellow top in my 2013 LX570 the same week, and it is doing fine, with similar sporadic use like the IS.

 

They used to make great batteries decades ago. Since the production has moved to Hecho Mexico they suck. I had nothing else but problems w the Red Top. In my opinion they're not worth the extra money. I buy OEM Toyota/Lexus instead

 

Apologies if you were just making a joke, but "Hecho en Mexico" is Spanish for "made in Mexico". The batteries are actually made in Monterrey.

 

Yes as in Monterrey Mexico, lol

https://www.optimabatteries.com/expe...ove-to-mexico/

 

All I can add is I had a similar problem to OP on my Yamaha street bike. It has over 13.1:1 c/r and if the weather and bike are too cold or too hot it wouldn't carry enough cranking amps to start it.

Replaced it with Yusa AGM LAB. No problems at all after that.

 

I have been using the Optima Red top battery for over 2 years on my IS, and did not run into any issues so far.

 

How frequently is yours driven? Wifes ISC sits for days unused. I am thinking now that the red top needs frequent recharging to keep it up. I now have the red top out on my workbench and charged to 100 percent with an Optima brand charger. It is disconnected and I am monitoring its voltage daily to see how it holds its charge without any chance of draw from the car.

Car now has a new Exide battery installed, but wife has not been anywhere in the week since I btought it home and installed it.

BTW, finding a battery with a smooth outer case to fit inside the black plastic cover was a challenge. I finally just ditched the cover. The new battery has side handles that prevent the cover from fitting over it. It seems secure ; I think the plastic cover was just a cosmetic thing.

 

You could get a Battery Tender to keep it charged when the car is not driven.

 

I have to laugh at this one. My wife would just drive off trailing Battery Tender wires behind her.

I actually do own 7 Battery Tenders and 1 Optima battery maintainer that I use on my other other cars, my trailer winch battery, my tractor, my generator, and my UTV. The metal case on one I tried on wife’s ISC has battle damage from being attacked by the IS fan blades. She is not a car person.

 

I returned the red top, and replaced it with an Exide 4 year AGM. The Exide is holding charge just fine. It has gone a week so far without the car being driven. he Exidet started at 12.93V, the morning after installation and at the end of the week just sitting in the car is at 12.92V....

No more red tops for me.

 

Makes you wonder why OPTIMA maker would put out the statement like this...

https://www.optimabatteries.com/expe...uck-the-truth/