Which battery runs what???

Totally guessing.. but they both may be for the engine, connected in parallel. Check the wiring. I always thought coach batteries were in the coach part.. somewhere, like under the steps.

Actually its pretty simple. First look for identificstion. Second remove the ground csble from one and see what does not work. Third, the batyeries will lead to an isolator, so you can check thst.

Hi Deni,

Is it a diesel engine?

Welcome to the forums!

Deni wrote:
We just bought our first RV....a 1996 Tioga Montara. We can't find anything that tells us which battery under the truck hood runs what. There is one on the left side of the engine...and one on the right. Is there any way to know which is which?

Two batteries under the hood does sound like a diesel. Does it have the 7.3L Powerstroke diesel? If so, the two batteries are wired together in parallel and act like one large battery.

You should have separate batteries for the coach, somewhere else.

Charles

No...it's a gasoline engine.

Thank you donn0128! I should have thought of that!!

On Fleetwood Tioga RVs with two batteries under the hood. Chassis battery is on the drivers side and house battery is on passengers side

House battery should be marked deep cycle, if it's still readable.

mikhen wrote:
House battery should be marked deep cycle, if it's still readable.

That's what I was thinking, too. One battery serving as

Chassis/Engine/Star/Crank (people call same thing different names) and it should be your typical Automotive Battery. If you can read the label, words like "Cranking Amps, Amps at X Degrees" etc.

The other serving as

Coach/House/Accessory (terminology again) and it's basically a "Trolling Motor Battery" if you're asking for one at a place like Walmart (which I recommend, by the way - good batteries at decent price available nearly everywhere nearly 24 hours a day 7 days a week). And it should be labeled "Marine Deep Cycle, Trolling" etc. With an Amp-Hour rating and probably include terminals for nuts or wingnuts in addition to the traditional Battery Posts.

Just had to be dure it wasn't diesel

Pic of an RV Deep Cycle "House/Coach" battery. Notice the "RV" designation on the label, and the 3/8" stud terminals in addition to the typical battery posts used on "Chassis" batteries.