How long does a c6 have to sit immobile before you really need the tender? What brands models seem to work best on the c6?
thanks!

 

Many opinions on tenders. Me, I like Schumacher. Used 2 for a few years now! At Wally world around $20

Time to need, way too many differences in cars, batteries and use to give a good answer.
Some cars overnight most cars should go at least 10 days, some more

 

Ctek multi us 3300

 

My C6 has 40,000 miles on it, is a DD and has never needed a tender. I'm on the original battery, car bought September 2006.

 

I've left my '08 sitting with no tender for 2 months at a time. It depends on the battery condition.

 

I have 3 years on the 2007. I go regularly 30-40 days without a tender in winter. I have not had a reason to buy one yet. The car is in a garage.

 

You wouldn't need a tender because it is a daily driver in Texas.

Northern state drivers that put their cars away for the winter do need one, though not always. I haven't bought one as I try to get mine out every few weeks during the winter if the weather (and thus the lack of road salt!) allows.

 

Im in Tx.. but drive the car once a week.. maybe once every 2 weeks.. winter is coming and the car might sit.. just want to make sure a few weeks arent going to kill it if i need to drive it.

 

My car sits for weeks at a time and I've never had a problem with it starting when I do get in it and drive it. It's probably a good idea to use a tender for extended periods of sitting if you want to get the most life out of the battery though.

 

Automatic chargers can overcharge a battery. Schumachers are great chargers but should not be left unattended. Smart or 3+ stage chargers like the Battery Tender or CTEK can be left on indefinately without fear of overcharging.

The gain to using a smart charger (3, 4, 5, 6, even 8 stages) is prolonged battery life. Alternators charge to approximately 90%. The different stages of a smart charger vary current and voltage while measuring a battery's temperature. 1st stage is usually steady current with increasing voltage, 2nd stage is decreasing current with steady state voltage, 3rd stage is lower, steady state voltage and low, steady current, sometimes pulsed.

To give you an example of how they pay for themselves I have two Harley's. One has a Odessey battery that is 10 years old, the other has the stock AGM battery that is 6 years old. Those little batteries usually don't last long. Cheap ones last a year or two, Harley's AGMs are 3-5. The 10 yo battery is showing signs of weakening, which is one of the great things about Odessey's. They are military grade and don't fail catastrophically. They gradually fail giving the user plenty of warning. The stock 6 yo battery is still cranking as though new.

Regular use of a smart charger prolongs battery life and will pay for itself in one saved battery. It's more about prolonging battery life than keeping your battery charged, though those who store vehicles over winter months need both.

 

"Schumachers are great chargers but should not be left unattended."
Quoted from above!

In my post i referenced a Schumacher TENDER. No one I know leaves a CHARGER on uatttended. Schumacher makes a good tender, I have used 2 for years. I also have a Schumacher CHARGER for about 20 years, it does a good job also

 

When I first got my C5, the battery would drop too far in about 10 days of non use. Then after about 6 months, it would last about 3 to 4 weeks. I chalked that up to getting the battery fully charged by running the car, but have no facts to back that up.

I put a battery tender on when I park for the winter, for more than 3 weeks, and the original battery lasted about 6 years, I replaced with an Autozone battery, treated it the same, and it is still good.

 

8 weeks, and it started right up for you ? That is the longest time I've heard of. Did you disconnect the neg. battery cable ?

 

What he said except I only have one Harley Btw, I use two Battery Tenders (Brand Name)

 

Remember it also depends on how far the car is driven when it is driven. If the car is driven once a week, but only for a mile or two, the battery will never get back to full charge. If mine leaves the garage, it goes a minimum of 35 miles, which is town and back. Never had an issue with the car not starting, with about 3 weeks being the max time it sat.

 

According to the manual about 3 weeks, I use a battery tender works fine for me.

 

I have Schumacher SE-1-12S Maintainers on my 05 GTO & 2000 & 2009 Vettes. The battery in the 2000 is the original battery, over ten years old. It's been hooked up to the Schumacher for it's entire life. I leave the cars on the tenders all winter & never have had a problem. Most guys in my CC use them also with perfect results. My C6 goes dead after about six days so it is going back to the dealer. This started before I installed the tender.

 

My car is fine for two to three weeks. Any time the car sits for longer than two weeks I connect the battery tender. Purchased my car in March of 2006, still have the original battery.