2450 L RV Conversion Advice

Good Day

I am looking for some advice on converting this former wildland firefighting unit into a RV. I am working with a truck builder to have the base body built and then I will complete the interior. The base box or body will be around 14' L 8' w with a interior head clearance of 7'. Any thoughts I should go to a longer body?
Brian IMG_5121.jpg IMG_5120.jpg


Adventurer Wannabe
Nice truck
Will you mount the box or will the truck builder? I ask because mounting on a Unimog is different to almost any other truck and you will end up with problems unless the builder knows what he's doing.
Have a look in the forum for mounting threads.
How much rear overhang will you have with a 14" box (is it the same as the existing equipment shelf?). The main factor limiting the length is overhang and what that will do to your exit angle.
Also 7' head clearance sounds a little high (but I don't know how tall you are:) ). In most parts of the world it's good to try to stay under 3.5m.


As ianc said, pay particular attention to the way the body is to be mounted as Mogs have a huge amount of chassis flex... If you can get the mounts sat in the center and on the outside of the chassis then you can keep the body low. Re length, the back of that rack that is already on there looks to be a sensible amount of overhang.. It 'looks right', so I'd be going with that length. If the chassis will allow it, hang your twin spare wheels off the rear of the chassis and not the body. It makes for a lighter less stressed body. Re height, you want standing room inside + 50/100mm. No more.. No need. The lower you can keep it the better the center of gravity. Lastly, weight.... Be very mindful of it at all times throughout the build... 2 spares, 4+ batteries, fuel, water, food, clothes, gas, cookers, fridges, windows etc etc etc all mounts up. You can soon have an 8+ tonne Mog.. I'm playing safe and starting with a 12 tonner, but even with that I want it to end up under 8 tonnes finished. Great looking Mog you have and what looks to be an ideal wheelbase too! Good luck, and ask lots of questions... I know I will be once I have a shed to put the truck in!! :)
That looks like the Unimog that is/was for sale in Alberta It sold at auction for 45k from the military then popped up on Kijiji for 85k, now it's down to 65k. Still 20k over the auction sale price. If it's indeed the same truck.

Mercedes has a body builder's site that says what you can and cannot do on a Unimog, it includes things like where you can and can't drill into the frame, how much room is needed between the box and the cab for flex, how much overhang you can have on the frame, mounting points, etc.
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Hello Uppercrust

I am looking at a body built by ITB here in Coaldale Alberta. I will then finish the inside with custom cabinets. How has your project turned out? I'm interested in any advice you have.

If you are planning on having a company build a body for the back, be sure to get ahold of the Mercedes Benz Body builder manuals. Unimog frames are designed to flex and if you compromise that system you risk damaging the Unimog or more likely, tearing your body apart.
Nice truck!

Are those fold down steps on the outside of the rear box? That would be cool.

The rear should hopefully already have been mounted with Merc's three point flexing torsion free design so you could just build up from that. Redesigning, rebuilding and lowering is a lot of work and cost for a small amount of gain IMHO, and it will still be a big truck that will obviously still be too big for some places.

Too much weight too far back and the rear axle acts as a pivot unloading the front and eventually overloading the back. Keep it all as light as possible!

Add the overdrive for about £5K GBP plus fitting if it hasn't already (for reducing the gap between 7th and 8th which annoyed me and was a bit big, not to increase cruising speed), an exhaust brake and ideally working gears. New 14.00R20 or 395 85R20 Michelin XZLs if getting towards ten years old (they're date stamped), or just for peace of mind. Fire trucks tyres may get a lot of abuse!

When I first bought our Mog camper in about 2008 from Atkinson Vos in the UK I was concerned about its height at 3.9m. Someone with travel experience in Africa said you roughly spend one third of your time travelling, one third waiting, and one third living in the box. So too big and you compromise the Mog while driving, too small and you drive each other nuts while living. Our taller than most height was because it had the double bed over the cab which with a good map (to avoid low bridges etc) was almost never a problem. When we did get on each others nerves one of us could escape to the "bedroom", so that extra truck height meant we could stay sane more often than if it was a more confined box. The 3.5m max comes from http://www.silkroute.org.uk/equipment/choosevan.htm but it's that one man's opinion from his experience. Someone on this site said the one bridge in an Ex Soviet country he came across at 3.5m they allowed him to drive across the train line instead.

Draw out the minimum size you want the bathroom, kitchen worktop, dining table (2,3 or 4 seats?), fixed or convertible or raising beds, and see how small a box you can squeeze it into. Look on Unicat, Action Mobil and Blissmobil's websites for what they think works, and the first two at least have been doing it for a long time. Or this one for a family of five but aiming to live mostly outside. Quite compromised I would think but worked for them for a long time;



We sold our Mog when we went from two to three and a dog. Our new non-Mog camper box length is almost as small as one single, one double bed and a dinette (all fixed) I think would fit into and ended up 5.8m long.

Because of the torsion free mounting plus clearance to allow for the twist plus long travel coils plus big tyres a Mog will never be a low profile camper without an elevating roof. So I wouldn't get too hung up on the height other than with the same as length, weight, width, extras, battery, fuel and water capacity- as big as needed as small as possible. Which should definitely end up within Mercedes guidelines (probably :))
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