Transit Diesel Engine Preventive Maintenance develops the competencies required to inspect, service, and maintain the diesel engines used in transit vehicles — engine systems and their operation, scheduled servicing, fuel and air systems, emissions aftertreatment, cooling and lubrication, and the diagnosis of common engine faults at the maintenance level.
Within the SCNS taxonomy, DIM is the Diesel Mechanics prefix, and the 0-level number identifies this as postsecondary adult vocational (PSAV) coursework — zero college credits, 120 clock hours. It appears at approximately three Florida institutions.
Transit diesel engines work harder than almost any other application: constant stop-and-go duty, extended idling, heavy loads, and high annual mileage. That duty cycle drives the maintenance requirements, and it is why transit engine work is a specialization rather than general diesel work with a different badge.
These are PSAV clock-hour courses within Florida's Transit Maintenance programme, structured as a series of occupational completion points (OCPs) — each a discrete, employable competency block rather than a term of general study. A student may complete one OCP and go to work, or stack several. Colleges commonly package them as Bus Transit Technician I and II certificates.
| Course | Title | Clock hours |
|---|---|---|
| DIM0810 | Transit Equipment Preventive Maintenance Technician | 200 |
| DIM0811 | Transit Basic Electrical Systems Technician | 120 |
| DIM0812 | Transit Wheelchair Lift/Ramp Technician | 60 |
| DIM0813 | Transit Diesel Engine Preventive Maintenance Technician | 120 |
| DIM0814 | Transit Steering and Suspension Technician | 120 |
| DIM0820 | Transit Hydraulics Technician | 60 |
⚠ These hour values are derived, not quoted from a fetched framework. The FLDOE curriculum frameworks are the authoritative source, and fldoe.org currently refuses automated retrieval — the values above were assembled from search results reporting the OCP structure, cross-checked against the Hillsborough Community College programme listing. They are internally consistent, but verify against your own institution's published framework before relying on the exact number, and note that FLDOE frameworks are revised on a published cycle.
Note also that DIM0812 (Wheelchair Lift/Ramp) is part of the series but is not currently in this repository's queue, and that the transit series is distinct from the general diesel series this repository already carries — DIM0101C, DIM0102C, DIM0104C, and DIM0105C — which run at 150 to 300 hours per block. Same prefix, different programme. SCNS equivalency does not cross numbers.
The most operationally important content in this course, and the reason transit engine work differs from over-the-road diesel work.
Modern diesel emissions control depends on heat. The diesel particulate filter accumulates soot and must periodically regenerate — burning the soot off at high exhaust temperature — and selective catalytic reduction requires adequate temperature to convert NOx using diesel exhaust fluid. Both assume the engine spends meaningful time under load.
Transit duty violates that assumption. Stop-and-go service and extended idling produce low exhaust temperatures, incomplete regeneration, soot accumulation, and the derates and forced regenerations that take buses out of service. It is one of the most common transit maintenance complaints and it is a duty-cycle problem rather than a component failure.
What a technician needs to know: the difference between passive, active, and parked regeneration and when each is appropriate; that DEF quality and contamination matter — it is a specified fluid, it degrades with heat and age, and contaminated DEF damages the SCR system expensively; and that a derate is a protective response, not a fault to be bypassed. Tampering with or disabling emissions control is a federal violation, and enforcement against delete devices and their installers has been substantial.
Worth highlighting because it is the technique that separates reactive shops from well-run fleets. Oil analysis — sampling engine oil and having it laboratory-tested — reports wear metals, contamination, coolant intrusion, fuel dilution, and additive depletion, and it does so before the failure those things predict.
The value is in the trend, not the single sample: a rising copper or iron level over successive samples indicates a developing wear problem while there is still time to plan the repair rather than recover a bus from a route. Fleets that sample systematically also use the data to extend or shorten drain intervals with evidence rather than by guess.
For a technician, the practical skills are taking a representative sample correctly — same point, same conditions, clean equipment — and reading the report in context rather than reacting to a single flagged value.
The single most important current safety content, and one that older training material does not cover adequately.
Transit fleets are electrifying. Battery-electric and hybrid buses are in service across Florida agencies, and they operate at voltages that are lethal — traction battery systems run at hundreds of volts DC, far beyond anything in a conventional diesel bus. The hazards are different in kind from 12- or 24-volt work:
Conventional hazards remain and are also serious: lifting and jacking a vehicle of this mass, compressed air systems that store substantial energy, diesel exhaust in an enclosed shop requiring ventilation, hot surfaces and coolant under pressure, and working under a raised vehicle, where the discipline is that a jack is a lifting device and a stand is a supporting device. Verify current manufacturer procedures rather than relying on general guidance.
A practical requirement students frequently do not anticipate. Transit maintenance technicians move buses — into and out of bays, onto lifts, and on road tests — and most transit agencies therefore require or strongly prefer a commercial driver's licence with a passenger endorsement.
Three things to know. The CDL is obtained through the Florida Department of Highway Safety and Motor Vehicles, not through the college, and federal Entry-Level Driver Training requirements apply to new applicants for a Class A or B CDL and certain endorsements — training must be delivered by a provider listed on the FMCSA Training Provider Registry. It carries a DOT medical certification requirement, which is a genuine disqualifier for some conditions and is worth checking early. And transit agencies operate under federal drug and alcohol testing rules for safety-sensitive positions, including pre-employment, random, and post-accident testing.
Rule 11 applies — CDL and ELDT requirements have changed and continue to; verify current requirements with FLHSMV and FMCSA rather than relying on this guide. The practical advice: find out what the agency you want to work for requires before you finish the programme, because the CDL takes time.
The PSAV certificate demonstrates training; ASE certification demonstrates verified competence, and it is what transfers between employers and frequently what determines pay grade.
The relevant series for this work is the ASE Transit Bus (H-series) certification — H1 through H8, covering compressed natural gas engines, diesel engines, drive train, brakes, suspension and steering, electrical/electronic systems, heating and air conditioning, and preventive maintenance and inspection. Certification requires passing the examination and documenting relevant hands-on work experience, and certifications must be renewed periodically.
Two practical points. Employers frequently pay for testing and offer certification pay differentials, so ask. And begin documenting work experience from the first job, because reconstructing it later is difficult — the same advice this repository gives for PMI credentials and for Florida addiction counselling hours.
Worth stating plainly because it is the most attractive feature of this pathway and students often do not know it.
Transit maintenance technicians typically work for public transit agencies — county and regional authorities — or for the contractors that operate service for them. That produces a set of employment characteristics unusual among skilled trades:
Florida-specific: agencies including Miami-Dade Transit, HART in Tampa, LYNX in Orlando, Broward County Transit, JTA in Jacksonville, and Votran in Volusia County maintain substantial fleets, and the statewide technician workforce has an ageing profile — which is the underlying reason these programmes exist. Note also that transit maintenance is federally funded in part, which brings FTA requirements and a documentation culture with it.
DIM0813C is 120 clock hours of combined classroom and shop instruction. Assessment is by demonstrated service performed to specification and by written assessment on systems and emissions. Expect the aftertreatment content to be the part that most requires current material — emissions systems have changed substantially across engine model years, and a section using an older engine will not cover what is in a current fleet. Confirm what your programme's shop vehicles actually are.
The 0-level SCNS number identifies this as postsecondary adult vocational coursework, measured in clock hours with zero college credit. PSAV coursework does not transfer into a college-credit programme the way a 1000- or 2000-level course does. What exists instead is articulation — Florida's Gold Standard Career Pathways and local agreements may award credit toward a related A.S. for completing an entire programme or occupational completion point, not for individual courses, and never automatically. Get a written evaluation from the receiving institution before assuming.
In this trade the certificate matters less than what an employer can verify you can do. ASE certification, a CDL, and demonstrable diagnostic ability are the currency — see below.
The first digit of an SCNS number denotes the year of offering, not transferability. Courses at the 1000 and 2000 levels transfer transparently between Florida public institutions; the boundary that matters is 2000 to 3000. A 0-level number sits outside that system entirely — it is PSAV clock-hour coursework carrying no college credit.
Generated September 2, 2026 · Updated September 2, 2026