12 volt plug

Of the two 12 volt sockets on the Ford E350 dash on our 2100, does anyone know if either is connected to house battery?  We currently have a small Engel cooler for frozen or refrigerated items while traveling and the 12 volt side is hardwired into our lithium batteries directly but thinking about adding a second cooler.  While dry camping, they only pull a couple of amps when running and we never have to think about outside ambient temps in desert.
On a different subject, we’re going to replace our 5-6 year old tires and would like you knowledgeable folks a real world opinion on what you’re currently riding on…thanks to all for responses.
Greg & Jan
2018 PC 2100
Central Valley, Ca.

The dashboard 12v sockets come off the Ford truck battery. There is a 12v socket in the front cabinet, passenger side, next to TV that runs off house batteries.

We have Hercules tires.

John and Holly's answer is correct about the 12v outlets.

We use Michelin tires.

Michelin (and most other brands) says it's tires last 10 years unless worn out or you see heavy sidewall cracking.

From Michelin website:

Keep five years in mind
After five years or more in use, your tires should be thoroughly inspected at least once per year by a professional.

Ten years is a maximum
If the tires haven't been replaced 10 years after their date of manufacture, as a precaution, Michelin recommends replacing them with new tires. Even if they appear to be in usable condition and have not worn down to the tread wear indicator. This applies to spare tires as well.

Okay, thanks to all for your response…we’ll go to our local tire dealer and have a though inspection performed… btw, guess Earl forgot to install 12 volt socket in our cabinet…oh well, they surely got everything else right as this unit after 30,000 miles+ is truly incredible! By far the best built RV we’ve ever owned and we’ve had Safari, Airstream , 2 Winnebago Views and others.

We had one of the original Hankooks shred on us at the 5 year point. We always kept appropriate inflation based upon RV weight and using a TPMS.

We had always used Michelins on our previous RV with good results and we switched to the Michelin Agilis tires.

You'll find everyone has their own opinion of the best tire.

Lots of opinions on different brands, how long to keep them, etc. on this and all RV forums.   I believe tire life is affected by a lot of factors but I always err on the side of caution.   On any vehicle there are just a few square inches of tire with my life riding on them and I replace them long before they are "worn out".   How vehicles are stored is another major factor I would offer for consideration.   

The socket is inside the cabinet, on the front wall, next to the little red light/button you push when you use the outside/physical cable connection. It looks like the old cigarette lighter port - open, round hole.

Earl sold them, he didn't build them but I doubt they'd miss that outlet.

On my 2019 2552 there is a switch between the two 12v sockets that will switch  power from the coach battery to the house battery.

Lots of opinions on different brands, how long to keep them, etc. on this and all RV forums.   I believe tire life is affected by a lot of factors but I always err on the side of caution.   On any vehicle there are just a few square inches of tire with my life riding on them and I replace them long before they are "worn out".   How vehicles are stored is another major factor I would offer for consideration.   

Exactly!  Which is why I *NEVER* skimp on tires or brakes.