Diamond, Illinois — small community, serious freight corridor. When a truck goes down in Diamond, J&A Fleet is the call.
J&A Fleet Maintenance provides mobile diesel repair and emergency roadside service in Diamond and the surrounding Grundy County. When your truck can’t move, we come to you — roadside, yard, or dock — with a quoted rate and a certified tech.
Diamond fleets also fall inside our Coal City and Braidwood coverage, with full-shop backup from both our Morris and Gardner locations.
Our Services
- Diesel & Engine Repair — Root-cause diagnostics and repair for all Class 6–8 diesel engines — no guesswork, no unnecessary parts.
- Semi-Truck Roadside Assistance — 24/7 mobile dispatch across northeastern Illinois — certified techs come to your truck, not the other way around.
- Air Brake Repair — Chambers, valves, compressors, and frozen lines — complete air brake system service and DOT compliance.
- Electrical & Alternator — Advanced diagnostics trace electrical faults to the source — wiring, batteries, alternators, and charging systems.
- Cooling, Radiator & A/C — Radiator, coolant system, and cab A/C repair — keeping engines and drivers running at the right temperature.
- Transmission Repair — Automatic and manual transmissions, differentials, and clutches — diagnosed before a single part is ordered.
- Welding & Fabrication — Certified welders for frame repair, trailer structural work, and custom fabrication — shop or roadside.
Pricing — Same Rate Whether You’re Stranded or Not
J&A Fleet quotes our hourly rate, minimum, and any surcharges before we dispatch. The price doesn’t change because you’re stranded. Overcharging a customer in a tough spot is something you’ll never experience with J&A Fleet.
Shop Work — Morris and Gardner shops
For repairs requiring a full shop facility — transmission rebuild, major engine work, welding and fabrication, DOT inspections — our Morris and Gardner shops handle the work. We coordinate transport if needed.
Fleet Maintenance Programs in Diamond
Running a fleet through the Diamond / Route 113 corridor? Ask about our mobile maintenance program. We come to your yard on a schedule, keep your units DOT-compliant, and reduce the unplanned downtime that eats into margins.
Diamond is small enough that a lot of shops skip it. We don’t. See a J&A truck rolling through this stretch of Grundy County and need help? Just ask — that’s coverage, not a coincidence.
Most calls into our Diamond coverage area break down into a handful of repeat problems: a dead alternator or a parasitic draw that leaves a truck no-start at a dock, a low-air buzzer tripping on the shoulder, or a coolant leak that turns into an overheat call in stop-and-go traffic. Whatever brings a Grundy County fleet to a stop, the process is the same — diagnose to the root, quote the rate, fix it once. Our mobile techs carry the diagnostic tools and common parts to close out most of these calls on the first visit, instead of sending a driver back out for a second trip.
Whether it’s an emergency call or a routine visit, a stop in Diamond is also a chance to catch what a driver hasn’t noticed yet — worn linings, a slow air leak, a marker light that’s about to fail an inspection. Our techs flag it instead of just fixing what you called about. For fleets running Grundy County on a repeat basis, a standing maintenance schedule usually costs less over a year than a string of one-off roadside calls billed separately, one truck at a time.
Down in Diamond?
Tell us where the truck is and what it’s doing. We’ll give you an ETA and a quoted rate — then get a certified tech moving toward you.
