GXV Patagonia on the Kenworth K370 chassis

waveslider

Outdoorsman
We were fairly limited in that due to my height restrictions, the bath on ours had to be situated directly over the grey tank near the rear axle

We are also only a couple with no kids or needs for additional sleeping room, however we REALLY enjoy having the full dinette in the front with benches on either side. That is our main hang out area and it can be converted to another bed if we happen to have a guest.

We like being able to look out both sides and the front via the passthru in the front. Therefore using the passthru as another window wall so to speak.

In my opinion, doing a small box-like passthru on the kenworth like you see on the safari extremes would be taking away one of the absolute best features of the kenworth- the huge pass thru in the front. My $.02

I guess it’s worth mentioning that we designed our vehicle as a refuge from being outside all day. We are not interested in “living” in our vehicle but rather it’s a mobile hunting and fishing cabin that we can retire to after a long day of hunting or fishing or otherwise being out in the elements.

So having a lot of windows and comfortable seating was a huge priority for us so we could warm and dry as needed.
 

gregmchugh

Observer
Thank you both. I am curious about the resource that is limiting when boondocking. Is it water / diesel / fridge and freezer space?

Depends on lots of factors with your truck configuration and how you use your resources, here are some estimates based on our way of doing things (these are quick rough estimates)...

Our truck has 200 gal tanks for diesel fuel so assuming you have them full enough you should not be limited by diesel fuel for either heating/hot water or generator use if needed (lack of solar or use of air conditioning would lead to running the generator).

Our truck has 130 gal of fresh water but we have the capability to pump water from streams, rivers, or lakes if available. Depending on how you use the water it should not be the limiting factor. We don’t make much effort to conserve water and could probably go 3-4 weeks without getting water. We have a drinking water filter (Seagull) so we drink water from the water tank rather than carry bottled drinking water as some seem to do.

Our cassette toilet or our 23 gal greywater tank would likely be the limiting factor for us if we could not dump them where we are boondocked. We carry a spare cassette so we can go a week or so with two cassettes. Grey water limit is based on how many showers you take but normally we could go a week or so between grey water dumping. No limit if you can dump where you are boondocked. We typically are traveling enough to dump the cassette and grey water in pit toilets or dump stations. If you boondock in an area where you could dig a hole and bury the cassette contents and could dump grey water there would no time limit.

Food as a limit would depend on what type of food you carry and whether it requires refrigeration or not (we don’t hunt or fish so no option to obtain food while boondocking). The standard Vitrifrigo fridge/freezer used in GXV trucks is pretty good sized and you could easily add a chest fridge/freezer to get more capacity or select a larger unit to start with. If we planned to boondock for an extended period I think we could carry enough food to not have it limit our stay but there is a limit I suppose of maybe a month or so (longer if not as much food needing refrigeration).

Bottom line, if we planned to boondock in one place for a month we could do it without much effort and probably longer if we could get more water or work harder at conserving water or selecting the right food (not too much fresh food or frozen food) and having a way to dump the cassette and grey tank. In reality, we have never thought about this very much since we have tended to be moving enough to limit our stays in one spot to about 2-3 weeks in places with access to a pit toilet and then being close to places to get supplies. We could probably go longer than a month if we planned ahead and maybe made some changes to the truck configuration. In reality, our major travel for the first two years has been to Alaska where we have not done extended boondocking away from access to water and dump options.

And again, these are some rough estimates, maybe even WAG’s...
 

38snubby

Active member
Depends on lots of factors with your truck configuration and how you use your resources, here are some estimates based on our way of doing things (these are quick rough estimates)...

Our truck has 200 gal tanks for diesel fuel so assuming you have them full enough you should not be limited by diesel fuel for either heating/hot water or generator use if needed (lack of solar or use of air conditioning would lead to running the generator).

Our truck has 130 gal of fresh water but we have the capability to pump water from streams, rivers, or lakes if available. Depending on how you use the water it should not be the limiting factor. We don’t make much effort to conserve water and could probably go 3-4 weeks without getting water. We have a drinking water filter (Seagull) so we drink water from the water tank rather than carry bottled drinking water as some seem to do.

Our cassette toilet or our 23 gal greywater tank would likely be the limiting factor for us if we could not dump them where we are boondocked. We carry a spare cassette so we can go a week or so with two cassettes. Grey water limit is based on how many showers you take but normally we could go a week or so between grey water dumping. No limit if you can dump where you are boondocked. We typically are traveling enough to dump the cassette and grey water in pit toilets or dump stations. If you boondock in an area where you could dig a hole and bury the cassette contents and could dump grey water there would no time limit.

Food as a limit would depend on what type of food you carry and whether it requires refrigeration or not (we don’t hunt or fish so no option to obtain food while boondocking). The standard Vitrifrigo fridge/freezer used in GXV trucks is pretty good sized and you could easily add a chest fridge/freezer to get more capacity or select a larger unit to start with. If we planned to boondock for an extended period I think we could carry enough food to not have it limit our stay but there is a limit I suppose of maybe a month or so (longer if not as much food needing refrigeration).

Bottom line, if we planned to boondock in one place for a month we could do it without much effort and probably longer if we could get more water or work harder at conserving water or selecting the right food (not too much fresh food or frozen food) and having a way to dump the cassette and grey tank. In reality, we have never thought about this very much since we have tended to be moving enough to limit our stays in one spot to about 2-3 weeks in places with access to a pit toilet and then being close to places to get supplies. We could probably go longer than a month if we planned ahead and maybe made some changes to the truck configuration. In reality, our major travel for the first two years has been to Alaska where we have not done extended boondocking away from access to water and dump options.

And again, these are some rough estimates, maybe even WAG’s...

Greg thank you for taking the time to respond to these questions your answers are well thought out and very enlightening to those of us who are interested in these big vehicles. There are not many of you who take the time to respond. Cheers.
 

Zuri

New member
Depends on lots of factors with your truck configuration and how you use your resources, here are some estimates based on our way of doing things (these are quick rough estimates)...

<snip>

Thank you so much for being so generous with your time and effort. Two weeks is plenty for us so the truck is a good fit.

We are thinking about 2 months a year in the summer in BC / the Yukon / Alaska and three months a year in the desert South West and Mexico in the winter so not full timing. We live on Vancouver Island.
 

gregmchugh

Observer
Keep in mind that there are options that make the truck more suited for longer boondocking periods such as composting toilets or other toilet options.
 

wfv56

Active member
Greg I see your spending time in a cold climate. It appears that GXV places the lithium batteries in a unheated space. Any problems with cold weather charging?
 

38snubby

Active member
Greg I see your spending time in a cold climate. It appears that GXV places the lithium batteries in a unheated space. Any problems with cold weather charging?

That is incorrect. The batteries are contained within the actual box that GXV builds so they are in a heated place the same as the water tanks. @gregmchugh however is far better equipped to explain this as I do not own one of these rigs.
 
Last edited:

gregmchugh

Observer
So the “garage” slash rear storage area is heated?

Not necessarily actively heated...

The answers to all the issues of cold weather capabilities are dependent on the specific truck. GXV is not building a standard design as you would get from EarthCruiser (for instance) where each truck is designed with specific cold weather capabilities. While there are general designs for the systems, each GXV truck can have variations which will effect cold weather capabilities.

I am most familiar with the Kenworth Patagonias so I can discuss some of the differences.

All the trucks I have seen have a cassette toilet or some other type of self contained toilet in the heated area of the cabin so that is not an issue. The grey tank is generally located in a lower outside compartment so it does need to be considered in the cold weather capabilities. The fresh water tank is located under the bed and while this is not an actively heated area it should not get cold enough to freeze even at the floor level which would be the place where the greatest heat loss would occur.

The rear storage area can have active heating or just passive heating through the walls from the actively heated cabin area.

There are two standard heating systems, the Webasto Dual Top (hot air and water heating) and the Webasto Thermo 90 (hydronic heating using radiators and a heat exchanger for hot water heating).

Our truck, for instance, has a Webasto Dual Top located under a front bench seat in the cabin area with two hot air outlets along the baseboard on the driver side of the floor. Ours has no active heating in the rear storage which does limit our cold weather capability compared to trucks with active heating in that area. Another truck has the Webasto Dual Top located in the rear storage area with ducts up to the cabin for cold air input and hot air return. In this design, the rear storage area gets active heating from the Dual Top itself and the hot air ducts exiting the Dual Top. The ducts can be insulated to control the amount of heat given off in the rear storage area.

The Webasto Thermo 90 system allows a lot more options on heating various areas using radiators and you will see radiators in the bath area to heat it and to use to dry clothes/towels. Our truck has no Dual Top heat outlets in the bath so we need to keep the door open if we want to keep it warm sometimes. The Thermo 90 is usually located in a lower outside compartment along with the grey tank in the compartment (heat from the Thermo 90 keeps the grey tank from freezing, our truck with the Dual Top has an electric heating pad under the grey tank to prevent freezing).

So, as part of the design process it would be necessary to understand what type of cold weather capability you desire and make sure that the truck is designed to meet that need. If you want extreme cold capability then you would probably want active heating in any area where there is the possibility of freezing the water lines or lithium batteries at the temperatures you are designing for.

So, lithium batteries and water lines are the two items that are going to be effected by cold temperatures.
  1. The Lithium batteries are generally located in the rear storage area on the wall that separates the rear storage from the fresh water tank under the bed. The batteries, inverter, and solar controller are usually next to each other along with lots of other Mastervolt stuff. Assuming you are living in the truck, the heat given off by the inverter, solar controller, and the lithium cells will keep the batteries above freezing since the wall they are mounted on does get heated somewhat from the cabin heat. I have seen batteries mounted on the side wall which could result in more heat loss through the wall though. I think the issue of lithium battery temperature is probably not something that is a concern even for rear storage areas that are not actively heated but at extreme cold temps it may be something to address.
  2. The issue of water lines freezing is something that needs to be addressed since they generally run along the floor in the cabin and back to the water tank under the bed and to the water pump which is located in the rear storage area along with a water filter. Without active heating in the area where the water lines run along the floor outside the active heating in the cabin you will have a lower temperature limit set by the loss of heat through the floor resulting in a frozen water line. Again, something to address as part of the design process with GXV based on your cold weather requirements.
These trucks can be made as cold proof as you want but you do need to address it as part of the design process.
 

waveslider

Outdoorsman
As a contrast to Greg's (excellent) outline, our truck is a little different in that our Webasto Dual Top is located in the rear compartment - otherwise called the 'underbed storage' area and has ducts that snake up to the front cabin area.

The main reason we had the heating unit installed into the rear area is (again) due to my height and the fact that our shower pan sits directly on the floor (vs a subfloor that lines could run under) it had to go in the back.

Not only does the webasto unit itself put off a fair bit of heat through its metal case - we also discovered that the ducting also put off a lot of heat as it carried the warm air to the front of the cabin. A little heat back there is good - a lot of heat isn't great. There was enough heat radiating from the ducts that we worked with GXV to have some insulated ducts sent over and we re-threaded the ductwork with insulation and now it's basically perfect with zero risk of things getting too cold in the storage area which is where the plumbing/water lines as well as the lithium battery is housed.

Our grey water tank is located as Greg described - in an outside storage cabinet- but since we virtually never camp in organized campsites, we pretty much always have our grey water valve open so no real risk of it freezing and having an issue. But it does have a heating pad under the tank to prevent freezing if we need it.

Probably the coldest we've been is zero degree weather for a short period of time and didn't have any issues but as Greg mentions, if you intend to be in sub-zero temps for extended periods you should take that into consideration and discuss with the folks at GXV to make the right choices. A perfect example of that is we chose NOT to get the dual-pane glass windows which are more thermally efficient than the plastic dual pane windows we got but we wanted some larger window options (and more windows) that would have made that choice a considerable investment that we didn't see the value. However, if we were going to spend long time periods in extreme weather conditions, I would recommend the high end windows for sure.

The way we look at it, if the weather is that crappy, we're just going to go somewhere the weather is nicer. Isn't that the point of having one of these?
 

gregmchugh

Observer
As a contrast to Greg's (excellent) outline, our truck is a little different in that our Webasto Dual Top is located in the rear compartment - otherwise called the 'underbed storage' area and has ducts that snake up to the front cabin area.

The main reason we had the heating unit installed into the rear area is (again) due to my height and the fact that our shower pan sits directly on the floor (vs a subfloor that lines could run under) it had to go in the back.

Not only does the webasto unit itself put off a fair bit of heat through its metal case - we also discovered that the ducting also put off a lot of heat as it carried the warm air to the front of the cabin. A little heat back there is good - a lot of heat isn't great. There was enough heat radiating from the ducts that we worked with GXV to have some insulated ducts sent over and we re-threaded the ductwork with insulation and now it's basically perfect with zero risk of things getting too cold in the storage area which is where the plumbing/water lines as well as the lithium battery is housed.

Our grey water tank is located as Greg described - in an outside storage cabinet- but since we virtually never camp in organized campsites, we pretty much always have our grey water valve open so no real risk of it freezing and having an issue. But it does have a heating pad under the tank to prevent freezing if we need it.

Probably the coldest we've been is zero degree weather for a short period of time and didn't have any issues but as Greg mentions, if you intend to be in sub-zero temps for extended periods you should take that into consideration and discuss with the folks at GXV to make the right choices. A perfect example of that is we chose NOT to get the dual-pane glass windows which are more thermally efficient than the plastic dual pane windows we got but we wanted some larger window options (and more windows) that would have made that choice a considerable investment that we didn't see the value. However, if we were going to spend long time periods in extreme weather conditions, I would recommend the high end windows for sure.

The way we look at it, if the weather is that crappy, we're just going to go somewhere the weather is nicer. Isn't that the point of having one of these?
The move to someplace warmer is also our usual approach to dealing with cold and snow but our daughter had a baby in BC in January so we have been here for awhile. :)
 

wfv56

Active member
Thanks guys. I have been pondering a change to lithium in my rig. The only thing that gave me pause was the warnings not to charge below freezing. I view Mastervolt as a leader in this field and had been curious how this was addressed. Thanks so much for the detailed response. I have really appreciated the time Waveslider and Greg have donated to these threads
 

Forum statistics

Threads
185,812
Messages
2,878,459
Members
225,352
Latest member
ritabooke
Top