This is the official build thread for the Just Differentials / Nitro Gear & Axle 2004 Ford F450 4x4 Motorhome. For more up to date photos, check our Facebook page album:
F450 4x4 Motorhome FB Album
We were in need of a tow / stay vehicle for traveling to national off road events. Travel in snow is also a bit of a concern. We needed something that could sleep 2-4 comfortable, and still tow 10k lbs. Options considered a Diesel Pusher (too big, 2wd), Truck with camper (too small), Class C (Van type too light duty, 2wd, gasser engine would not suffice), then we found the solution. Also we wanted a vehicle that would showcase the products that we offer. The F450 4x4 chassis fit the bill.
We started with a 2004 Xplorer Xcursion Motorhome This was already a good start. These are a rare 4x4 diesel RV which suits our needs well. Fortunately, Xplorer gave us a good headstart. the RV is a nice 1 piece fiberglass construction, has a slide out kitchen, and queen bed at the rear, and on the cabover. It's also fully set up for four seasons use. It came equipped with a nice Herd Alloy bumper and Alcoa alloy 19.5's:
Although it was 4wd, it didn't really look the part. the home portion of the RV keeps the rear wheels really tucked, and the factory 225/70r19.5 tires are only about 31", which look to small for our liking. Functionally we wanted the additional ground clearance of larger tires. Also a SRW conversion seemed ideal for winter traction and to avoid wedged rocks on the duals when off road.
To go single, we needed a tire with a high capacity. The loaded wet weight is about 14k (5k front 9k rear). The factory duals were rated at 3350 ea (13,400 lbs total rear axle). We contacted Rickson Wheels for some custom 22.5" bolt on steel wheels to run big rig tires. They actually had a full set ready to go that were take-offs from the Turtle V Expedition vehicle. This seemed like an obvious choice, but what about tires? Most of the 22.5 semi truck tires have a highway type tread. We wanted something aggressive. We ended up finding some Double Coin RLB800 11R22.5 tires. These have an aggressive tread, and rated at 6940 lb each. Sounds great, but they measure 42" tall. That's a big step from the factory 31" tires.
To clear the tires the truck was definately in need of some suspension. We wanted to keep it as low of COG as possible so didnt want a big lift. After consulting Bushwacker, we found their Cut-out fender flares would clear bout a 40" tire with a leveling kit on a Superduty. With the help of Ben at National Springs, we found are OE rear packs were only rated for 8750 lb, already too soft. We chose some 12,000 pound pair, and added a custom 1" full size block bolted into the leaf pack. The front we used std Leaveling mini pack. This yielded about 2.5" lift. To minimize body roll we also installed Hellwig 1.5" swaybars and extended front links. Since the rear is fiberglass, we removed the OEM flares and trimmed out about 5" around the arch. Since the singles are narrower we decided to run without flares on the rear.
Aaron & Robert at our local Les Schwab truck center, jumped at the oppertunity to try cramming 42" Big Rig Traction tires on a motorhome. Keeping it local helped out here as they offered to test fit them. To their surprise the tires fit great!
The Herd Alloy bumper looked nice before, but was going to require significant modifications to match the new fenderline and would not hold a winch. We contacted ASFIR 4x4 for their new modular front winch bumper, these are great as they can be shipped UPS due to the 3 piece construction. It housed the new Milemarker 15k lb winch nicely!
The timing was good, as we just started stocking a full line of ratios and traction devices for medium duty trucks. This means we have gears in stock for this S110 as well as S130 & S135. The Factory Dana Corporation 4.30 gears were fine with 31's but needed more for 42". We chose 5.38 gears, and a Eaton Corporation Truetrac LSD. This gives us near stock gearing. Actually just a few RPM's lower on the highway than stock. We used our part number DS110-538-OE ring & pinion, MK DS110 install kit, TT 504038 Truetrac LSD and DAN130647 ABS tone Ring. This Monster weighed 173 lbs!
Stay tuned for more to come.
-Rigid Industries Interior Lighting and Light bars
-Spyntech live spindle conversion w/ MileMarker hubs
-Nitro 35 spline Chromoly axles
-Nitro front 5.38 Ring & Pinion
-Nitro Xtreme Diff cover
-ARB Twin High Output compressor
-AMP Research PowerSteps
-Remote reservoir Shocks.