I recently switched my TM from a 2005 MG Tour 82 to a new MK Fortrex 80 lb 24 V. I never had a problem with my MG draining my batteries after a full day of fishing. The Fortrex drains the batteries after 6 hours of fishing.

What's up with this? Is this normal?

I'm thinking about purchasing 2 new lead acid batteries. Or do I need to upgrade to Lithium? Any help would be appreciated.

How old are your batteries?

They are 3-4 years old but they both show 12+ volts after charging. No dry cells. And they hold a charge. I've checked them in 2 hour increments after charging.

Only 12vdc after charging is low. Should be more like 12.7

I would purchase 2 new marine deep cycle batteries. Shop around, should be some on sale with rebates!

I have fished with a 24V Ulterra with Auto Deploy and Stow for 8 hours and it never ran the batteries down.

I had a cell go bad in a flooded lead acid deep cycle battery and it charged up fine and sat for 3 days and still showed 12.5V static charge. As soon as I applied a load, the voltage dropped to less than 11V and it would not operate my trolling motor.

I have since replaced both trolling batteries with AGM Deep Cycle Marine batteries

A "false voltage" will also "float" on a defective battery that has been charged but not had a load applied. Run the TM for 5 minutes then check again. An even better option is to take the batteries to an auto parts store, where they will usually load test a battery for free. If they apply a 20-25 amp load and the voltage craters, you have a lead anchor shaped like a battery.