4 new batteries and an inverter problems?

I guaranty it's 1.5, which roughly coincides with the nitro 17 power draw I see when googling for it.

Most group 31 batteries will be about 100 amp/hour batteries. If you have 4 of them, that 400 amp hours. This means in general you can draw 1 amp for 400 hours, or 10 amps for 40 hours, or.....100 amps for 4 hours.
Your company tech needs to look at the TA installation.

 

I'm not there, but you give no signs that the truck is in jeopardy, so....
There's usually more to a high watt inverter hook up than just battery pos and neg. But this is up to your company tech to look at and make sure TA didn't put a wire in the wrong place etc.
In an earlier reply, it was mentioned that you may have underlying alternator issues. This is a very good possibility. Again, your tech will look into it.
And yes, a loose or compromised connection at the batteries or other high amp draw locations, can cause all sorts of intermittent and frustrating issues.

 

That's bs. In other words, TA put the cheapest junk batteries in possible, maybe because they were told to by your company. "?" Modern batteries take cold very well. That's not to say that 20 below zero F wont or can't cause the batteries to reduce their output, but decent batteries today can take very cold temps and do quite well. There are still a lot of very old myths about batteries that continue to be held and perpetuated. Many years ago, it was said that batteries would loose charge if set on concrete or soil for lengths of time, so one would always set the batteries on a block of wood. A lot of old people my age still continue to use that old myth. Of course several of them also still believe that parking under a power line will drain your batteries, so... Basically TA installed, likely because they were told to so not pointing fingers of disdain, cheap cold cranking batteries. The originals, likely were still in when you played for 6 hours, were much higher quality batteries with driver comfort more in mind. Those batteries would be able to hold a charge much better for longer periods of time.
Probably in your situation, having company rules to follow, you're going to be best off buying your own either small inverter generator, or power supply that you can charge while driving. The batteries installed in the truck will stay there until they fail, and likely be replaced again with the least expensive set available. So, now ya know where you stand.

 

On a truck that new, I wonder if they can set it up to auto start the truck when the batteries reach a certain level. ? My Pete with the smart air apu does.

 

I would consider building or buying a small ' house system ' and run independent of the truck. BLUETTI AC180P Solar Portable Power Station | 1,800W 1,440Wh

You could charge/run your devices on the truck inverter while it's running then switch to your house system after shutdown for the night saving your cranking batts.