RoamIt -
I have driven various FMTV derivatives in many countries on 4 or 5 Continents (do Canada and New Zealand count as Continents?).
And by driven, I mean having lived in (and under) these vehicles for weeks if not months at a time in hot/cold/dry/wet places.
Hands down the BEST riding leaf sprung vehicles I've ever used (and the 4-wheeled models rival MOST coil sprung vehicles as well).
As far as the basic layout/drivetrain goes the FMTV has MUCH more going for it than MOST other 4x4 "expeditionary" vehicles.
Short overhangs, relatively long wheelbases and wide tracks make for a comfortable and stable vehicle in most conditions/terrains.
The earlier CAT 3116 engine is MUCH more tolerant of "third world" operation and servicing than the later CAT 3126 engine.
However, in my experience additional fuel filtration using CAT 2-micron filters & water separators should be used for both engines.
Ungoverned, low geared models are quite capable of speeds in excess of 75 mph without exceeding any design parameters.
Built like the proverbial tank – the 4x4 M1078 weighs around 16,500 lbs, and the 6x6 M1083 weighs around 19,600 lbs.
The FMTV was designed to withstand rough usage – imposed by the environment/terrain AND by the occupants/usage.
No fancy high strength steel (which can complicate welding repairs) – just REAL thick, straightforward carbon steel structural pieces.
I've NEVER been left stranded by a PROPERLY maintained FMTV – and therein lies the main issue with these trucks.
They were designed to be maintained in a workshop environment with access to the necessary technical documentation/tools.
Main issues in military usage are primarily caused by –
Operator error – I observed the Peter Principle in operation all too frequently
Operational expediencies – necessity dictating doing things/going places not designed for
Readiness pressures – damaged units returned to operational status WITHOUT proper repairs being completed (or undertaken)
As far as actual breakdowns go, the VAST majority I saw (or experienced) were due to the Allison transmission wiring harness.
And most of these were caused by broken wiring and/or moisture ingress into theoretically waterproof connectors.
Fortunately, dielectric grease will remedy virtually all of the potential connector issues (in the transmission and elsewhere).
And conductive grease will remedy most of the remaining electrical issues around the vehicle.
Note: WD-40 IS NOT an acceptable substitute for either of these lubricants!
Spraying Fluid Film on the chassis/running gear will help to GREATLY decrease the propensity for mud/water to affect components.
Yes, keeping an FMTV running in rough conditions, is MUCH easier if you are mechanically inclined AND understand its systems.
Have a sufficiently comprehensive tool kit to cope with remote servicing, AND learn how to use the tools BEFORE departing.
Obtain ALL the military maintenance manuals and take a printed copy (on waterproof paper) on any long-distance trip.
Take 2 hydraulic jacks AND 2 adjustable height axle stands (ideally with screw threads NOT pins/teeth) – with load spreaders for all.
Take 2 tarps – one to use as a rain/sun canopy during servicing, and the other as a ground cloth/dirty part wrapper/fluids collector.
So; would I choose an FMTV as an expedition vehicle today?
It wouldn't be my first (or second) choice, but I might be willing to IF I could –
Replace the complete braking system with hydraulic disc brakes (I HATE air and air over hydraulic brakes with a passion!).
Replace the Allison automatic transmission with a 10 to 13 speed manual Roadranger (I HATE automatic transmissions equally)
However, when all is said and done, the FMTV is simply too bloated for my liking, and its load capacity really SUCKS!
The M1078 has a payload capacity of 5,000 lbs and a towing capacity of just over 10,000 lbs.
The M1083 has a payload capacity of 10,000 lbs and a towing capacity of 21,000 lbs.
ABSOLUTELY pathetic for both variants in both usage categories.
Granted, I look at vehicles like the FMTV as WORKING/TOWING trucks first, and as "camper haulers" a distant second.
But, having driven the length and breadth of Africa more than a few times (long ago) in flatbed Unimog's that were regularly used to help families/villages I encountered on my travels, my view of vehicle suitability is likely MUCH different than most westerners.
When the going gets REALLY rough, an "old skool" Unimog with its integrated torque tube drivetrain/suspension has NO equal!
Shame that all the Unimog models have too short of a wheelbase to be OPTIMALLY effective as an expeditionary vehicle IMO.
