2018 Ram ProMaster 2500 Conversion
A self-directed engineering project transforming a high-roof cargo shell into a fully livable, four-season mobile home.
The Finished Build
Build Through Time
Placeholder images — filter by build phase. Real photos coming soon.
- Vehicle Platform
- 2018 Ram ProMaster 2500 High Roof
- Battery Bank
- ~200 Ah LiFePO₄
- Solar Array
- 400W (4× 100W Panels)
- Climate Control
- MaxxAir Fan + 12V Diesel Heater
- Controller Logic
- Custom ESP32 w/ Web UI
- Water System
- 6 gal Fresh / Gray, Foot Pump
Scope & Structural Build
Purchased as a blank slate with ~800 miles, this project was executed primarily outdoors during the 2020 COVID shutdowns. The build required converting a bare metal shell into a livable space within a strict 4-month deadline before starting a full-time engineering role in Ohio.
- Framing & Insulation: Designed wooden structural framing attached via sheet metal screws and construction adhesive for vibration damping. Insulated with 1–2" sheep wool for moisture management and sound deadening.
- Fabrication: Cut chassis openings for a roof fan and sliding window. Constructed integrated cabinetry, a fixed bed platform, and under-bed storage in a highly space-constrained volume.
- Repurposed Materials: Reworked timber from deconstructed kitchen cabinets into custom van cabinetry. Implemented compliant, friction-based catch latches to ensure doors remained closed under road loads.
Electrical Grid (12 VDC)
Designed a robust off-grid power system anchored by ~200 Ah of LiFePO₄ batteries. All conductors and fuses were sized based on current draw and run length to mitigate voltage drop and overheating risks.
- Solar Array: Fabricated a custom roof rack using McMaster-Carr L-brackets and marine-grade hardware (nylon insert lock nuts) to mount a 400W array. Validated aerodynamic stability by instrumenting the roof with a GoPro at highway speeds (80 mph).
- Power Management: Integrated an MPPT solar charge controller and a user-switchable 12V-to-12V DC-DC alternator charger for redundancy while driving.
- Safety: Utilized corrugated loom for abrasion protection in corner regions and centralized fusing to isolate faults.
Engineering Deep Dive: Embedded Heater Control
The 12V diesel heater stock remote offered poor UX and no automation. I iteratively engineered a custom control system to solve this, moving from mechanical actuation to a fully digital solution.
Servo-Based (Arduino)
Used hobby servos to physically press buttons on the stock remote. Validated the UX concept but suffered from mechanical alignment issues and hot-glue failures.
Relay-Based PCB
Soldered leads directly to the remote PCB, using relays to emulate button presses electrically. Improved reliability but encountered intermittent relay contact faults.
RF Decoding & ESP32
Sniffed and decoded the 433MHz RF protocol. Built a transmitter-only system on an ESP32 with a local Web UI for smartphone control, temperature thresholds, and status monitoring.
Systems & Iterative Design
Water & Plumbing
Implemented a 6-gallon fresh/gray water system via foot pump. Root Cause Analysis: After noticing contamination in the original single-piece jug, redesigned the system with quick-disconnect components for full disassembly and drying to improve hygiene.
Thermal Management
Retrofitted a diesel heater for winter living. Addressed rear-door drafts by diagnosing seal failure caused by debris build-up. For summer, improvised a cooling solution ducting cab A/C to the living area via a thermal barrier.
3D Printed Additions
Designed functional components including a sliding-bolt lock for the fridge rail (preventing extension during braking) and custom waterproof enclosures for the ESP32 control electronics.
"Achieved a reliable 'home on wheels' capable of supporting extended travel to remote parks... and iteratively refined the build over multiple trips home."