Hate to say it but time to put the C7 to bed for winter. I read somewhere to (not) fill gas tank because the chemicals in the gas leave a film over gas tank sensors.. Also I have 500 hundred miles on last oil change. Would it be necessary to change it for the winter to avoid any caustic damage to engine from oil breakdown. Using Mobile synthetic 5/30. Thanks for input.

 

Fill the tank up, maybe put some Stabil in the tank. I'd worry less about the 500 miles on the oil change and more on the time since. What does your oil life monitor say? If its above 90% I'd say don't bother. Inflate the tires a little, maybe 35psi and just let it hibernate.

 

1/4 tank.

 

Not necessary to change oil.

 

Unless you live in the Frozen Tundra, then just hook it up to a battery tender. I live in the Northeast and use to go through the whole winterizing routine for all of my garage queens, but those 60+ degree days in December, January, etc., have deterred those endeavors.

Edit: To answer your questions: If your oil life is good, then wait until Spring, and yes, it is recommended that you don’t fill the gas tank. I personally wouldn’t use any gas additives, but opinions differ

 

Full tank is fine, no additives needed, inflate tires to 35psi, wait till Spring for oil change and that is it.

 

Summit Racing's Top 10 Tips for storing your vehicle for the winter:

 

Don't forget the battery maintainer.....

 

Stabil yes. Use the marine grade (blue) Stabil which will take care of any moisture (which you will have some if there is any air in the tank). I personally fill the tank to minimize condensation from what little air is left in the tank. Sulfur used to cause a problem with fuel sensors. A couple years ago the EPA mandated much lower sulfur levels in gasoline so it is probably not an issue any more. Google "EPA Tier 3 gasoline" for more info.

 

Normally I use Top Tier, 93 octane gas but I fill up with non-ethanol 91 octane (highest I can get) for my last two tank fulls and run the level down to under 1/4 before storing. The non-ethanol does not attract moisture like the gas with ethanol. This way I don't worry about a partially filled tank. In the spring I fill it again with Top Tier. The fuel tank sensors are a very expensive repair so I try to minimize the chance of damage. I haven't had any problems in 4 years of ownership.

 

That's what I do here in South Jersey. Mine doesn't sleep long...

 

You are right, ethanol is hygroscopic, meaning it attracts moisture from the air. Water will not dissolve in ethanol free gas, it will dissolve in ethanol. A good test to verify you are getting ethanol free gas is to put a small amount of the gasoline in a glass jar and add a drop of food coloring which is dyed water. If it forms beads on the bottom, there is no ethanol in the gas. If it dissolves, there is ethanol. The ethanol free gas will prevent additional moisture from being absorbed into the gas tank. There will be a small amount of moisture in the air in the gas tank but it will not be absorbed by the ethanol free gas. I don't use ethanol free gas in my C7, rather I just fill it up to minimize the air volume (and thus the amount of moisture). I do the same with my C3 Pro-Street which requires 93 octane so I don't have a choice with that car as like you said ethanol free gas above 91 octane is very hard to find. All my small engines always have marine grade Stabil in them except for storage, when I drain the tanks. My boat and 4 wheelers are always run with and get stored with full tanks of ethanol free gas and marine grade Stabil. All these methods work and your program works too except that I would recommend adding at least the basic Stabil to minimize fuel degradation. Keep in mind that fuel Stabilizers have a shelf life (2 years from opening the bottle for marine grade Stabil).

I understand the sensor concern, but if you read up on the new sulfur content regulations you will see that there is but a small fraction of sulfur in gasoline today compared to not too long ago and not likely to be a problem anymore.

 

I live in Ohio and drive mine all year long as long as the roads aren't wet, have salt residue, slush or snow. The longest I've gone in 7 years of vette ownership is about 3 weeks without driving them. I feel for you guys having to look at them in a garage for months at a time.

 

mine can go months at at time, has for years. I dont overfill tires or do anything special just disconnect the battery
Being as yours has a lot of electronics perhaps a tender thats it. The rest is a waste of energy

 

Not really necessarily to do anything to winterized if being stored less than 9>10 months except keep hooked up to a battery tender.

 

Do not fill up your tank because it could screw up the tank sensor. I personally would NEVER leave old oil in the engine.

 

I have always changed the oil when putting the car away for the winter, but with the C7, time makes a difference. If you have say 50% or so oil life remaining, just leave it in the car until you're ready to drive it in the spring. I also fill the tank and add Sta-Bil to help keep the gas fresh and some Techron to keep the sensor clean. A little extra air in the tires, a battery tender and maybe some pest repellent would be the rest of the routine.

 

This year I'll be storing my car in a facility with no outlets, so I'll be pulling the battery (will be in storage for 6 months). I've always changed the oil before storing, filled the tank, added Stabil, aired up the tires a few lbs, covered it and put the tender on it. When Spring finally arrives here in the NE I just take those extra lbs of air out of the tires and enjoy that first cruise of the season!

I'll follow that same routine this year with the exception of pulling the battery, as I've never had any kind of problems.

 

Battery tender for sure, stabilizer just in case, undecided about amount of gas in car.

I also crunge up newspapers and stick them in the exhaust to keep out mice.

 

I winterized mine by getting all season tires because I’m driving it!