4X4 Freightliner Off Grid Ambulance Build With Tesla Batteries

Hello Everyone!

We've been traveling full time in our modified truck camper for 18 months. Now we've begun building our dream rig for travel into Central and South America (whenever the current crisis is over and we can travel again!).

The Rig: 2002 Freightliner FL60, 8.3 Cummins and Allison transmission, 109k miles, factory 4x4, 14ft long box by Wheeled Coach.
We had been searching for a 4x4 ambulance for months and actually found this one through a post on expedition portal. We bought it sight unseen while quarantining in Mexico and it was 2 months before we got back to the state to see it in person. Very happy with our purchase so far.

Screen Shot 2020-03-31 at 5.00.00 PM.png. Screen Shot 2020-03-31 at 5.00.12 PM.png

The Floor Plan: We're good friends with Tom of @the_lost_box and we've spent a lot of time inside his ambulance conversion. Like him, this will be a total GUT. We are taking everything out and reusing almost nothing. We're trying to make this as 4 season capable as possible so we'll be splurging on closed cell spray foam insulation with another 1 inch of rigid foam over it. We'll have a shower and composting toilet, full kitchen and separate dinette and sleeping space. The shower pan will be recessed into the floor between the frame rails - that should be fun :p If you're interested in the floor plan, here's a YouTube video we just posted:
Build Materials: In a perfect world, we wouldn't use any wood in this rig. But alas, this world is far from perfect and our budget (see below) doesn't allow for a non-wood build. As a compromise, we won't be using any wood behind or on the exterior walls. These will all be skinned with HDPE sheets so if there ever is a leak behind the wall, we don't have to worry about mold. Hopefully the closed cell spray foam will create such a great barrier that it'll never leak but we've always gone with the adage of "it's not IF it will leak, but when". The inside structures will, begrudgingly, be wood, except for the shower area, of course.

Solar/Electrical Plan: Like our current rig, we will be 100% solar powered, no propane and no generator (we'll even have a mini split a/c running off solar). We'll start with 1200 watts of solar on the roof and we'll be using 2 Tesla Model S battery packs for the equivalent of 932 amp hrs on 12 volts. We'll be using all Victron components which is a splurge but this is hopefully our final rig so go big or go home! We'll be gutting as much wiring after demo as possible and plan to reuse it. We'll also be completely moving the electrical panel as our whole design depends on it.

Water Plan: 90 gallons of fresh water, 20 gallon grey tank with 12v remote release valve.

Heat/Hot Water: In our current rig we have a diesel Espar hydronic heater which heats the cabin and provides on demand hot water. We love it but the system is costly and so in order to reduce the budget (see below), we're going with an off brand airtronic diesel heater for cabin air and a Kuuma electric hot water heater. The water won't be instant hot which will be a change for us.

Truck Upgrades: For sure we'll be going with Continental MPT 81's all around. After talking with many overlanders we think the MPT's are the best tire for us. Not sure what wheels we're going with yet, still researching and open to suggestions! We'll be fabricating a custom rack for the back that will hold our spare tire, outside unit for the mini split and bikes. Right now we don't have any other truck upgrades planned. Once we're back on the road we can see how things are handling and go from there. I do know we have a leak in the air suspension that will need to be addressed.

The Budget: Eeekkkk.... everyone has one, right? LOL. Our budget for materials for the build is $33,000. We spent our months quarantining in Mexico building a spreadsheet of expenses for the entire build. Since we gutted and re-did our current truck camper with many of the same systems, we feel somewhat confident in our ability to budget :oops: but this is pretty nerve wracking!

The Timeline: We're driving in and working on this in every available hour we have. We only work part time so this leaves us with plenty of build time. We're hoping to have it "live-able" in 4 months.

We'll update this thread as we go. We do have a YouTube channel (Driven To Adventures) and Instagram (@DrivenToAdventures) as well.

Happy building, everyone!

Ginger & Greg
 
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Well... demo has been fun :p. If you'd like to see the whole demo video, it's here:
It took about 2 weeks to gut and clean up the wiring enough to move on. We removed so much wiring but at least we shouldn't need to buy any! Didn't take a ton of pictures but we took a lot of video.

IMG_20200701_164212_596.jpg. . IMG_0152 2.JPG
 

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Have you been looking into smaller-than-the-usual rooftop DC air conditioners? I have been doing just that recently.
A standard RV AC run off a 120v inverter will quickly draw down the batteries below the level that even 1200w solar (you do know that really means ~850w) can recover the next day if it is sunny.
PM me if you like.
 
Have you been looking into smaller-than-the-usual rooftop DC air conditioners? I have been doing just that recently.
A standard RV AC run off a 120v inverter will quickly draw down the batteries below the level that even 1200w solar (you do know that really means ~850w) can recover the next day if it is sunny.
PM me if you like.


Yes the RV a/c's are so inefficient which is why we were going with a mini split. I'm interested in the DC air conditioners you mentioned. Do you have any links?
 
Our entire floor plan revolved around moving this electrical panel. The weeks that Greg spent removing unnecessary wiring has paid off because not only was he able to move the panel, he reduced it to about 1/3 of its original size.
IMG_20200714_173223_870.jpg

Screenshot_20200714_171953.jpg

IMG_20200714_173223_867.jpg


Our new electrical closet (obviously still in progress) is now taking shape and our toilet will fit perfectly on the other side.

IMG_20200714_173223_868.jpg

Posted a floor plan video on YouTube last week if you're interested in the overall plan:
 

morbis

New member
I found this via your for-sale posting. Your last truck was really well done, especially for a truck camper.

This is epic! Good luck with the build.
 

mog

Kodiak Buckaroo
Yes the RV a/c's are so inefficient which is why we were going with a mini split. I'm interested in the DC air conditioners you mentioned. Do you have any links?
I just stumbled on this thread, congratulation on the truck!
My friends from Germany use this on their Mercedes with a 17-foot box and are very happy with it. They report no issues with running it off batteries overnight. Theirs is of course a 24 VDC unit, but I believe there are also 12 VDC units.

Split outside unit on the back of the cabin (under the cover)
eber3.jpg

eber1.jpgeber2.jpg
 

ohiobenz

Member
I just stumbled on this thread, congratulation on the truck!
My friends from Germany use this on their Mercedes with a 17-foot box and are very happy with it. They report no issues with running it off batteries overnight. Theirs is of course a 24 VDC unit, but I believe there are also 12 VDC units.

Split outside unit on the back of the cabin (under the cover)
View attachment 607988

View attachment 607989View attachment 607990
I'm surprised that 2200 BTU can cool a 17ft box.
 

ohiobenz

Member
Hello Everyone!

We've been traveling full time in our modified truck camper for 18 months. Now we've begun building our dream rig for travel into Central and South America (whenever the current crisis is over and we can travel again!).

The Rig: 2002 Freightliner FL60, 8.3 Cummins and Allison transmission, 109k miles, factory 4x4, 14ft long box by Wheeled Coach.
We had been searching for a 4x4 ambulance for months and actually found this one through a post on expedition portal. We bought it sight unseen while quarantining in Mexico and it was 2 months before we got back to the state to see it in person. Very happy with our purchase so far.

View attachment 597497. View attachment 597498

The Floor Plan: We're good friends with Tom of @the_lost_box and we've spent a lot of time inside his ambulance conversion. Like him, this will be a total GUT. We are taking everything out and reusing almost nothing. We're trying to make this as 4 season capable as possible so we'll be splurging on closed cell spray foam insulation with another 1 inch of rigid foam over it. We'll have a shower and composting toilet, full kitchen and separate dinette and sleeping space. The shower pan will be recessed into the floor between the frame rails - that should be fun :p If you're interested in the floor plan, here's a YouTube video we just posted:
Build Materials: In a perfect world, we wouldn't use any wood in this rig. But alas, this world is far from perfect and our budget (see below) doesn't allow for a non-wood build. As a compromise, we won't be using any wood behind or on the exterior walls. These will all be skinned with HDPE sheets so if there ever is a leak behind the wall, we don't have to worry about mold. Hopefully the closed cell spray foam will create such a great barrier that it'll never leak but we've always gone with the adage of "it's not IF it will leak, but when". The inside structures will, begrudgingly, be wood, except for the shower area, of course.

Solar/Electrical Plan: Like our current rig, we will be 100% solar powered, no propane and no generator (we'll even have a mini split a/c running off solar). We'll start with 1200 watts of solar on the roof and we'll be using 2 Tesla Model S battery packs for the equivalent of 932 amp hrs on 12 volts. We'll be using all Victron components which is a splurge but this is hopefully our final rig so go big or go home! We'll be gutting as much wiring after demo as possible and plan to reuse it. We'll also be completely moving the electrical panel as our whole design depends on it.

Water Plan: 90 gallons of fresh water, 20 gallon grey tank with 12v remote release valve.

Heat/Hot Water: In our current rig we have a diesel Espar hydronic heater which heats the cabin and provides on demand hot water. We love it but the system is costly and so in order to reduce the budget (see below), we're going with an off brand airtronic diesel heater for cabin air and a Kuuma electric hot water heater. The water won't be instant hot which will be a change for us.

Truck Upgrades: For sure we'll be going with Continental MPT 81's all around. After talking with many overlanders we think the MPT's are the best tire for us. Not sure what wheels we're going with yet, still researching and open to suggestions! We'll be fabricating a custom rack for the back that will hold our spare tire, outside unit for the mini split and bikes. Right now we don't have any other truck upgrades planned. Once we're back on the road we can see how things are handling and go from there. I do know we have a leak in the air suspension that will need to be addressed.

The Budget: Eeekkkk.... everyone has one, right? LOL. Our budget for materials for the build is $33,000. We spent our months quarantining in Mexico building a spreadsheet of expenses for the entire build. Since we gutted and re-did our current truck camper with many of the same systems, we feel somewhat confident in our ability to budget :oops: but this is pretty nerve wracking!

The Timeline: We're driving in and working on this in every available hour we have. We only work part time so this leaves us with plenty of build time. We're hoping to have it "live-able" in 4 months.

We'll update this thread as we go. We do have a YouTube channel (Driven To Adventures) and Instagram (@DrivenToAdventures) as well.

Happy building, everyone!

Ginger & Greg

Sounds very similar to my plans for the LMTV; 1340W 48v PV, 3.5k 28vdc backup genny, 2 slabs of Tesla S.
What are your BMS plans? Using the Tesla cooling/heating coils or not?
 

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