How long will a battery for trailer brakes last?


Well-known member
Gold Site Supporter
I've had my new18' trailer for about a year or so. The battery was replaced when I bought the trailer. But it's never been on the road with a truck that had the wiring to work the brakes or charge the battery. It has sat outside all year without being charged. Can I rely on this thing to work when I hook it up to my truck?


I would suggest a low-amp "trickle" charge, then test it. You can probably get one @ TSC for about $25.


Senior Member
Staff member
I agree with the Redneck in a trickle charger would be your best bet. I've had my trailer since January and pull it probably every couple of weeks. Anytime it is being pulled it is being charged as both the truck and the Suburban have the charge line hooked up. It always says "charging" when it is hooked up. So I don't know if it hasn't gotten full charge or it says that just because it is receiving power. When it is unhooked from the trucks, it shows green in the status window when I check it.


I have a trailer that's rarely used. Beforehand, I take the battery out and put it on one of the aforementioned trickle chargers. Within seconds, it's reading full charge. Those little batteries seem to really hold their charge when sitting.

I take them to a battery shop annually after it's about 4 years old for testing. They always test good up to about 8 years at which point it's lost some of its oomph. I then replace it.