GM: 2 batteries on a gasser. Why?
- Thread starter Nayov
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I used to work at a camper lot in the last millennium. It was common to put second batteries and a charging circuit in trucks that carried or towed RVs. They could use the second battery to provide lighting, water pump, etc. power in the RV without discharging the primary vehicle battery to the point it wouldn't start.
This is what happens when someone buys a truck for none truck things. All GM trucks have a nice spot under the hood for a second battery, for plowing and stationary operation they are great, you know truck stuff.
The 3/4 ton and up trucks can even be optioned with larger or dual alternators.
The 3/4 ton and up trucks can even be optioned with larger or dual alternators.
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Originally Posted By: ArrestMeRedZ
I used to work at a camper lot in the last millennium. It was common to put second batteries and a charging circuit in trucks that carried or towed RVs. They could use the second battery to provide lighting, water pump, etc. power in the RV without discharging the primary vehicle battery to the point it wouldn't start.
Yes, same on boats, called a "house" battery but then its not usually in parallel with the starting battery.
I used to work at a camper lot in the last millennium. It was common to put second batteries and a charging circuit in trucks that carried or towed RVs. They could use the second battery to provide lighting, water pump, etc. power in the RV without discharging the primary vehicle battery to the point it wouldn't start.
Yes, same on boats, called a "house" battery but then its not usually in parallel with the starting battery.
Odd how my 5.3L Sierra's headlamps dim noticeably when the fan, AC compressor or brake lamps are energized.
Fresh 'oversized' battery notwithstanding, I've investigated retrofitting the optional second battery setup. Its OE tray is already in situ as delivered.
Fresh 'oversized' battery notwithstanding, I've investigated retrofitting the optional second battery setup. Its OE tray is already in situ as delivered.
If it is popular to convert that gasoline truck to a Class C RV, Ambulance, or a box truck, then having a second battery does make sense.
However, if it is just the standard truck with a gasoline engine I don't see the point.
However, if it is just the standard truck with a gasoline engine I don't see the point.
Originally Posted By: Nayov
What part of towing requires a second battery?
Must have been a 5.3.
edit: I mean what extra electrical load is imposed by towing?
Electric trailer breaks and RV power.
What part of towing requires a second battery?
Must have been a 5.3.
edit: I mean what extra electrical load is imposed by towing?
Electric trailer breaks and RV power.
Originally Posted By: ls1mike
He said it was GM. No 5.7 in a GM in 2007.
Originally Posted By: Nayov
Woman brought in her truck (2007 w/ 5.7 GAS motor) for a new battery. She flipped when we told her it had 2 and both had to be replaced. Why 2 batteries on a gas motor pick up
truck, and is it possible to jury rig it so one can be used?
Did he?
Quote:
Why 2 batteries on a gas motor pick up
truck
-Plow
-winch
-lights
-HAM radio/amped CB
-RV power
-trailer brakes
-Tommy lift gate
-tow truck conversions
-Rescue/emergency vehicles
-cold starting
-heated seats
-heated mirrors
-running inverters to watch telletubbies on the DVD player.
He said it was GM. No 5.7 in a GM in 2007.
Originally Posted By: Nayov
Woman brought in her truck (2007 w/ 5.7 GAS motor) for a new battery. She flipped when we told her it had 2 and both had to be replaced. Why 2 batteries on a gas motor pick up
truck, and is it possible to jury rig it so one can be used?
Did he?
Quote:
Why 2 batteries on a gas motor pick up
truck
-Plow
-winch
-lights
-HAM radio/amped CB
-RV power
-trailer brakes
-Tommy lift gate
-tow truck conversions
-Rescue/emergency vehicles
-cold starting
-heated seats
-heated mirrors
-running inverters to watch telletubbies on the DVD player.
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On the GMT-900 trucks the passenger side battery is the "primary" with the driver side one being the auxiliary. Lots of reasons to have it, extreme cold weather starting is the biggest reason in my area but extra lights, plows, RV accessories, multi axle trailer brakes, anything else you can think of will run longer on a dual battery system if the alternator fails.
Originally Posted By: ls1mike
Originally Posted By: zrxkawboy
Originally Posted By: ls1mike
What 2007 has a 5.7?
a Dodge
He said it was GM. No 5.7 in a GM in 2007.
I don't see OP saying Gm? Someone else said it was an option on GM???? Am I reading incorrectly?
Originally Posted By: zrxkawboy
Originally Posted By: ls1mike
What 2007 has a 5.7?
a Dodge
He said it was GM. No 5.7 in a GM in 2007.
I don't see OP saying Gm? Someone else said it was an option on GM???? Am I reading incorrectly?
Ah ha. The title says GM. My bad lol
Originally Posted By: asand1
Originally Posted By: Nayov
What part of towing requires a second battery?
Must have been a 5.3.
edit: I mean what extra electrical load is imposed by towing?
Electric trailer breaks and RV power.
Electric brakes really don't draw much... I believe it's 3.6A at each wheel. A dual-axle trailer only needs max ~14A, and really more like 2/3 of that before they lock up, which you'd dial out at the controller.
Originally Posted By: Nayov
What part of towing requires a second battery?
Must have been a 5.3.
edit: I mean what extra electrical load is imposed by towing?
Electric trailer breaks and RV power.
Electric brakes really don't draw much... I believe it's 3.6A at each wheel. A dual-axle trailer only needs max ~14A, and really more like 2/3 of that before they lock up, which you'd dial out at the controller.
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