Fridge Power

nabcracker

New member
Depending on how your truck came from the factory, you might consider upgrading the alternator. My Power Wagon came with 160amp alt, and I thought it was great until I added a fridge and a second battery to support it. Wound up adding a second house battery to give me 150ah in the house bank plus 105ah in starting battery, plus a 270amp alt. Still not enough in the desert in summer temps. FWIW, the Warn winch on the PW draws 440 amps at max pull, rated at 12,000 pounds but is mostly 15,000 pound components. You will need way more juice than you think.

Where does one find the rating of the installed alt? I looked on the Window sticker that came with my truck, but alternator is not listed. I have a Laramie mega cab with 6.7 Cummins, not sure if Ram uses standard build packages for the chosen Trim level.
 

67cj5

Man On a Mission
Where does one find the rating of the installed alt? I looked on the Window sticker that came with my truck, but alternator is not listed. I have a Laramie mega cab with 6.7 Cummins, not sure if Ram uses standard build packages for the chosen Trim level.
Every thing about the Alternator should be on the Label/Tag which is normally stuck on one of the flat surfaces of the Alternator, either the Top or the bottom of it,

hope that helps,
 

john61ct

Adventurer
Or plug in the VIN to a lookup and get the full details on all options built.

Dealers of course but other online sources
 

nabcracker

New member
Update - while the shop was installing my new Titan Fuel tank, I took an Uber over to the local outdoor retailer and purchased the PLB40. Over a two week trip, it kept my eskie operating at 32f with minimum upset. The PLB40 was plugged into the factory in bed 7 pin plug via a converter to cig plug. Over the two weeks, with a few instances of not running the truck more than an hour over 2-3 days, I never saw below 50% capacity on the battery. I did have a few issues, mainly due to buying a unit that did not have the updated firmware, the battery would cut off after an hour of no draw. To overcome this, I kept a usb cable plugged into a power port which tricked the battery into staying on when the cooler was not calling for power. Dometic sent me a cable and firmware update which seems to be working without needing the usb cable. For long term, I am not sure how the battery will hold up bouncing around in the back of truck, I need to look at ways to securely hold battery on cushioned surface I think
 

john61ct

Adventurer
So you just feed nominal 12V to charge the unit? Any idea its max current draw?

Even if that is low, I'd put in a more secure connector than a ciggie port, personally like Anerson's Powerpole
 

nabcracker

New member
So you just feed nominal 12V to charge the unit? Any idea its max current draw?

Even if that is low, I'd put in a more secure connector than a ciggie port, personally like Anerson's Powerpole
I did not doing any measuring beyond grabbing beers each night and they were still cold. The DC charger provided by dometic has an anderson connector on the battery side and a cig/engel (two pole I think its called) plug on the power supply side. For the long term I think I will install an anderson or engel plug in the back of the truck.
 

Photobug

Active member
Where does one find the rating of the installed alt? I looked on the Window sticker that came with my truck, but alternator is not listed. I have a Laramie mega cab with 6.7 Cummins, not sure if Ram uses standard build packages for the chosen Trim level.
Go to Cummins forum to ask about your truck.


I would guess the alternator is 160a.
 

luthj

Engineer In Residence
You need to pull the build sheet for your vehicle. A google for option sheet, or build sheet plus the vehicles make will usually pull up a site where you can enter your vin.
 
Top