Who this guide is for
This guide is for an experienced heavy-duty or diesel technician who wants to work for themselves, bringing repairs to trucks instead of waiting for trucks to come to a bay. If you are planning a lighter, one-truck diesel mechanic service, see also how to start a mobile diesel mechanic business. This page focuses on building a business that serves fleets and roadside customers with medium and heavy trucks and trailers.
Step 1: Decide what you will fix, and for whom
Mobile truck repair covers very different kinds of work. Decide early, because it drives your tools, your truck and your prices.
- Roadside and emergency repair: tires, air leaks, brake chambers, belts, hoses, lighting, electrical faults and jump starts. Calls come at any hour and speed matters.
- Scheduled fleet service: preventive maintenance, DOT annual inspections, DVIR defect repairs and recall work at a customer's yard.
- Trailer and reefer work: brakes, lights, landing gear, doors and refrigeration units at distribution centers and yards.
- Heavy equipment: construction and agricultural machines on job sites.
Most new shops start with one or two of these and add more once they have steady customers. Scheduled fleet work makes cash flow predictable. Roadside work pays well per hour but is uneven.
Step 2: Study your market
Before you buy anything, find out who will call you:
- Truck stops, distribution centers, industrial parks and highway corridors within your service radius.
- Local fleets with 5 to 100 trucks that do not have their own shop.
- Fleets that have a shop but need overflow, after-hours or yard service.
- Towing companies and dealers that refer work they cannot handle.
Call or visit fleet managers and ask what they need, what they pay now, and what frustrates them about their current vendors. Slow response and poor paperwork are common complaints, and both are things a new business can do better from day one.
Step 3: Set up the legal business
The U.S. Small Business Administration lists the basic launch steps: choose a location, pick a business structure, choose a name, register the business, get federal and state tax IDs, apply for licenses and permits, open a business bank account, and get business insurance.
- Structure: many owners choose an LLC to separate personal and business liability. Talk with an accountant about taxes before you decide.
- EIN: the IRS issues an employer identification number free of charge, and online applications receive the number immediately. You need one to hire employees, and banks and fleet customers usually ask for it.
- Bank account: keep business money separate from day one. It makes taxes and loans easier.
Step 4: Check licenses, permits and DOT rules
Licensing depends on your state, county and city. SBA notes that most small businesses need a mix of federal and state licenses and permits, and that requirements and fees vary by activity and location. Common items for mobile repair include a general business license, a sales tax permit if you sell parts, and environmental permits for waste fluids. Some states also register or license repair businesses. See mobile mechanic licensing by state.
Your own service truck may bring federal rules too. Under 49 CFR 390.5, a vehicle used in interstate commerce with a gross vehicle weight rating of 10,001 pounds or more is a commercial motor vehicle. If your service truck meets that definition and crosses state lines, review the USDOT registration rules in 49 CFR 390.201 and the inspection and maintenance rules that come with them.
If you carry compressed gas cylinders, such as oxygen and acetylene, or packaged fluids that are hazardous materials, review the materials of trade exception in 49 CFR 173.6. It limits package sizes, for example cylinders of 220 pounds gross weight or less for Division 2.1 and 2.2 gases, and caps the total weight of materials of trade on a vehicle at 440 pounds, with some exceptions.
Step 5: Get insured
SBA says the federal government requires every business with employees to have workers' compensation, unemployment and disability insurance, and that some states require more. Beyond that, ask a commercial agent about general liability, commercial auto for your service truck, coverage for tools and equipment, and coverage for customer vehicles in your care. Fleet customers often require proof of insurance and may ask to be named as additional insured. See repair shop insurance for mobile mechanics.
Step 6: Build the service truck
Your truck is your shop. Plan it around the work you chose in Step 1:
- Air compressor and air lines.
- Generator or inverter, lighting for night work.
- Crane, if you will handle heavy components.
- Tire tools and, for roadside work, common tire sizes.
- Diagnostic laptop and adapters for the makes your customers run.
- Shelving and bins for parts you use every week.
- Fluid storage and spill kit.
Start with what your first customers need, and add equipment as revenue proves the demand. See how to set up a mobile service truck.
Step 7: Set your prices
Price so that every billable hour covers the truck, fuel, insurance, tools, software, and your own pay, with profit left over. Most mobile shops charge an hourly labor rate plus a service call or travel charge, a parts markup, and higher rates after hours. Write your rates down and print them on estimates and invoices so customers know them in advance.
For context, the U.S. Bureau of Labor Statistics reports a median annual wage of $61,770 for bus and truck mechanics and diesel engine specialists. That is employee pay, not a shop rate. Your rate has to cover far more than wages. See how much should I charge as a mobile mechanic and how to price mobile mechanic jobs.
Step 8: Win your first customers
- Visit fleets in person with a simple one-page rate sheet and proof of insurance.
- Offer a first PM or annual inspection so they can judge your work.
- Make it easy to reach you: one phone number answered live, with a fast quote and a clear arrival time.
- Ask truck stops and towing companies for referrals.
Fleets look for speed, clean paperwork and consistent pricing. See how to get fleet accounts.
Step 9: Put systems in place before you get busy
What works with one truck breaks at three. From the start, set up:
- A way to take calls, create jobs and assign them.
- Estimates the customer approves before work begins.
- Repair lines written as complaint, cause and correction. See 3 Cs.
- Invoices sent the same day, with photos.
- Records of inspections and repairs your fleet customers can use for their own files, which carriers must keep under 49 CFR 396.3.
- Bookkeeping that matches every payment to an invoice.
Step 10: Hiring your first technician
When you turn work away every week, it may be time to hire. Remember that employees bring payroll taxes, insurance and overtime rules. Under the Fair Labor Standards Act, covered nonexempt employees must receive overtime pay of at least one and one-half times their regular rate for hours worked over 40 in a workweek, according to the U.S. Department of Labor. Build that into after-hours pricing.
Common mistakes
- Buying a fully built truck before you know what customers need.
- Pricing below what the truck actually costs to run.
- Giving net 30 terms to every fleet without a credit check. See how to handle net 30 fleet terms.
- Keeping paperwork in text messages and notebooks.
- Skipping insurance details that fleets will ask for.
How MetaFleet helps
MetaFleet is shop software for mobile and in-shop diesel and heavy-equipment repair. It covers dispatch, estimates, digital inspections and DVIRs, preventive maintenance, invoicing, payments and service truck inventory. To see it on your own work, get a walkthrough.