A chassis sold into Costa Rica is a promise rather than a product, the promise that whatever body a local workshop bolts behind the cab will be carried honestly to the weighbridge, and the BJ1186VLPHK-1 is a promise the record writes in full numbers. This Aumark EST-M from the H2 heavy-truck line is an 18-tonne class chassis cab sold for Costa Rica in bare-chassis status, left-hand drive with a row-and-a-half flat-roof cab for two, a 5150 mm wheelbase inside an 8800 by 2320 by 2750 mm envelope, a 2200 mm body width, and the record's own line for the load it is built to carry, a stated cargo weight of 12 tonnes on a gross vehicle weight of 18000 kg. The applicable superstructure is dimensioned internally at 6800 by 2300 by 600 mm, and behind the cab the engineering is the one Central American fleets already know, a 6700 ml Dongfeng Cummins Euro III, a Shaanxi Fast eight-speed, 4.2 and 9 tonne axles at 4.556, air drums under ABS, tubeless 11R22.5 wheels with a spare, 200 litres of fuel and a wind deflector above the cab.
Buying a truck chassis instead of a completed vehicle is a deliberate strategy, and it changes what a specification sheet is for. The factory supplies the cab, the powertrain, the frame stations and the wheelbase, and the Costa Rican bodybuilder supplies the working end, the van box, the drop-side, the tanker or the refrigerated shell, sized to the customer's cargo rather than an import container's convenience, and the record supports that division honestly by publishing the applicable body footprint, 6800 by 2300 mm of deck with the board height the factory expects, which is 15.6 square metres of floor. The economics are real in every Central American market, because local bodybuilding keeps the steelwork wage-cheap, the repair loop short and the second body swap on the same chassis routine, a truck rebuilt around a new box instead of replaced. What the chassis buyer must therefore verify is not the body but the interface, the frame stations, the coupling points and the masses, and this listing's job is to make those numbers visible before the order.
The engine is the ISDe245 30 from Dongfeng Cummins, a 6700 ml in-line six calibrated to Euro III, recorded at 180 in a column headed kW/PS without a unit applied and 950 N·m with no engine-speed anchor published. The technology level is the point of the purchase, because a mechanical-era Euro III six carries no urea tank, no dosing module and no catalyst to poison, which suits a market where diesel quality varies between the port of Moín and the interior and where every taller workshop has rebuilt these engines from hand, and the 950 N·m figure sits squarely in the band that a loaded Costa Rican box body needs to pull away on the Central Valley ramps. The two blanks are commercial cautions rather than defects, since the certified unit of the 180 figure and the rpm window of the torque plateau belong to the engine nameplate and certificate, and a bodybuilder quoting payload economics on an inferred curve rather than the real one is guessing with someone else's freight.
The driveline continues the logic of torque survival over catalogue speed. A Shaanxi Fast 8JS118TA-B, the eleven-hundred-class eight-speed manual, carries visible headroom over the engine's published 950 N·m, which is the pairing that lets a clutch survive years of laden starts instead of months, and the 9 tonne rear axle geared at 4.556 is the mountain stepping of the family, busy enough that the turbocharged six stays inside its pull band on the West Valley climbs and sedate enough on the Panamericana straightaways. The front axle is rated 4.2 tonnes to carry the cab, engine and a loaded box's nose weight honestly, giving an installed axle sum of 13.2 tonnes, and a medium duty truck sold in chassis form should have its final mass numbers read from the certificate of the completed build, since body and payload share the remaining allowance and the road registration follows the finished machine rather than the bare frame.
Under the promised body, the structure is medium-duty engineering with a highway accent. The frame records a 234 mm section depth, suspension is leaf springs with three leaves forward and a four-plus-three progressive pack at the rear, and the wheels are tubeless 11R22.5 radials, seven including the spare, the modern fleet size with plug-repair speed, retread economics and stocking depth in every Costa Rican tyre shop from San José to Limón. The wind deflector is fitted rather than optional, which reads as a statement about the truck's working life, a box body on a sealed national network rather than a site machine on mud, and the 200 litre fuel tank with no larger unit listed sets the same sentence, a day-radius workhorse fuelled from the depot schedule. For the box body truck that most Costa Rican buyers will ultimately build behind this cab, the deflector and the tubeless specification are the two factory decisions that most directly cut the operating ledger.
The brake and control line is the work standard stated plainly, full air onto drums front and rear under an ABS control system, the combination that regional workshops machine cheaply and that grit, rain and Caribbean spray tolerate better than disc hardware in this duty, with drums protecting the price of the rebuild and ABS protecting the wet-season stop. What the record does not list is an auxiliary brake, no exhaust brake, retarder or engine brake anywhere in the fields, and on a chassis sold into a country of sustained gradients that omission belongs in the operator's training plan rather than the brochure, because descending energy in a laden box body must then be absorbed by gear selection and linings, which is a teachable discipline and a budgetable wear item but not a choice. The steering box is not named on this record either, and the type that ships belongs on the order confirmation so the local workshop knows what its shelves should hold.
Rolling stock, fuel and the mass fields deserve one careful paragraph because a chassis purchase is a mass-contract negotiation in disguise. The record states a gross vehicle weight of 18000 kg and a cargo weight of 12 tonnes, and the installed axles sum to 13.2 tonnes, so the honest reading for a fleet is that the certified payload of the completed vehicle is whatever the finished machine's certificate grants inside those published numbers once the bodybuilder's steel and the cab and fuel are weighed, and the wise sequence is to build the body on paper first, weigh the chassis once at delivery, and write the door payload from the certificate rather than from any header. The 200 litre tank, the long service logic of a rebodyable frame and the 234 mm rails all say the same thing, buy the interface right and the chassis will outlive three bodies, which is the arithmetic that makes a truck chassis cheaper per tonne-kilometre than the completed import it replaces.
The cab sits between the working cab and the crew cab, a row-and-a-half flat-roof body with two seats, and its stated equipment is the powered baseline rather than the stripped one, central locking and electric windows as standard, manual air conditioning on the standard line, MP3 entertainment and the deflector already counted above. The 2200 mm body width keeps the machine inside the regional envelope while the 8800 mm overall and 5150 mm wheelbase keep it turning through San José's older streets and Limón's port congestion, the geometry that makes a chassis cab genuinely buildable in a market rather than merely importable. Fleets ordering in volume will want the option ladder of this platform, electric air conditioning, MP5 head units and mirror packages, priced at quotation, because the Costa Rica specification on this record lists only the standard line and the buyer's comfort budget should be spent deliberately.
Three businesses fit this chassis and one reading does not. The primary case is the completed box, the insulated or dry van that Costa Rican bodybuilders mount on frames like this for produce, manufactured goods and retail replenishment between the Central Valley and both coasts, the natural life of a box body truck built on 15.6 square metres of certified floor. The second is the drop-side and stake body for construction supply, coffee and feed distribution, where the stated 600 mm board geometry is the starting drawing rather than the finish. The third is the tanker and service-body platform, because a chassis with published frame stations and a deflected, tubeless specification is the sane base for water, fuel and sanitation work for municipalities and contractors. What does not fit is expecting a completed vehicle's answered questions from a bare frame, since the body, the final masses and the certificate belong to the build that follows, and buyers who treat the chassis as the whole product will learn the difference at their own weighbridge rather than this record's.
Ownership economics for a bodybuilder-led market are exactly where this configuration is strongest, because the expensive parts, the Cummins-calibrated torque, the Fast gearbox, the air brakes and the tubeless wheels, are factory-fitted and regionally understood, while the variable part, the body, is local steel at local wages and can be renewed without renewing the truck. The watch items are the same three every Central American fleet already tracks, lining intervals on gradient routes fitted with no auxiliary brake on this record, fuel logistics honest to the 200 litre day, and driver discipline on descent speed taught before the first rainy season. State what this record does not contain, since a chassis is a contract about the future: no completed-vehicle tare, no axle weights at build, no torque rpm window, no certified power unit, no gradeability, top speed or consumption figure, no steering box type, no option ladder lines and no warranty or after-sales terms appear on this sheet, and none of it is claimed here, with the stated 18000 kg gross and 12 tonne cargo to be reconciled on the certificate of the finished machine. Send the body drawing, the cargo density and the route profile, and this medium duty truck frame can be confirmed at quotation as the platform that earns its keep on Costa Rican roads rather than admired as a picture of one.
