What changes when you quote a semi-truck
A tractor is not an engine with wheels. It is five systems with different owners, and each has its own ruling data point. Whoever quotes off the chassis brand gets four of the five wrong.
- The chassis does not define the part. A Kenworth T680 can carry a PACCAR MX-13 or a Cummins X15; a Freightliner Cascadia, a Detroit DD15 or a Cummins; an International LT, a Cummins or Navistar's own. The cab brand says little about what is underneath.
- Each system has its own number. Engine: the serial on the plate. Transmission: the gearbox model (Eaton Fuller, Allison) on its plate. Axles: the differential model (Meritor, Dana). Air brakes: chamber type and brake shoe size. Suspension: whether it runs leaf springs or air bags.
Maintenance and urgency
- Maintenance runs by mileage, not by whim. Every service brings the same list: oil, fuel, air and coolant filters plus the water separator. The number arrives in whatever brand the fleet uses and your counter crosses it to the one you stock. Crossing filters without getting it wrong is a trade of its own.
- Whoever is asking is out on the road. They send a photo of the plate, the stamped number or a voice note in trade slang. They almost never type a clean part number.
Want to see how Victoria quotes a part like this? Message us on WhatsApp and we show you live.
Message us on WhatsApp →The driver's words and what your catalog calls them
Trucking has its own language. If the counter does not speak it, the quote comes out wrong or does not come out at all.
| They ask for | Your catalog calls it | The data point you need |
|---|---|---|
| "the ratchet" | Brake slack adjuster | Manual or automatic, spline count and arm length |
| "the cross" | Driveshaft universal joint | Driveshaft series (1710, 1760, 1810) |
| "the bag" | Suspension air bag | Suspension brand and position (front axle, rear, cab) |
| "the can" | Brake chamber | Type (30/30, 24/30, 20/24) and whether it is service or parking |
| "the fifth" | Fifth wheel | Brand (Holland, Jost, Fontaine) and height |
| "the cable" | Clutch, throttle or parking brake cable | Gearbox model and chassis year |
What gets quoted most on a tractor, and with which data point
| System | What gets asked for | The data point that rules |
|---|---|---|
| Engine | Filters, injectors, turbo, water pump, belts | Engine serial. Cummins ISX, X15, Detroit DD15 and the rest each have their own guide |
| Transmission and clutch | Clutch, throwout bearing, cable, synchronizers | The gearbox model on its plate, for example Eaton Fuller RTLO or Allison |
| Axles and differential | Bearings, seals, u-joints, ring gears | Axle model (Meritor, Dana) and ratio |
| Air brakes | Shoes, drums, chambers, slack adjusters, valves | Chamber type, shoe size and valve brand (Bendix, Wabco) |
| Suspension | Air bags, shock absorbers, spring bushings | Suspension type and position |
| Cab and electrical | Lights, mirrors, sensors, windshield | Chassis make, model and year, with the 17-digit VIN |
Catalog examples: what gets asked for every day
Numbers exactly as they appear in the supplier catalogs Suplifai has already standardized. The price and the stock are always the ones in your catalog.
| Number | Part | Fits |
|---|---|---|
| LF9080 | Fleetguard oil filter | Cummins ISX; Freightliner Cascadia |
| LF3000 | Fleetguard oil filter | Cummins N14 and M11 |
| FF5488 | Fleetguard fuel filter | Crosses to WIX 33697 and Donaldson P550774 |
| FS1000 | Fleetguard water separator | Cummins N14 and M11; crosses to Donaldson P551000 |
| AF25139M | Fleetguard primary air filter | Freightliner Columbia |
| 4707Q | Relined brake shoe kit with hardware | Meritor tractor axle |
| 4515Q | Minor hardware kit for 4515 and 4524 shoes | Meritor brakes |
Look at the last column: the filter is defined by the engine, the shoe by the axle and the brake by the system brand. None of them by the cab brand.
How an AI quoting tool solves it
The flow, with Suplifai's Victoria as the example:
- The request comes in over WhatsApp: a number, a photo of the engine or gearbox plate, a voice note asking for "the ratchet on the rear axle" or the full service list.
- The AI identifies the system and the ruling data point: it knows "the cross" is the driveshaft joint and that it needs the series, not the chassis brand. If the data point is missing, it asks for it in a single question.
- It crosses against YOUR catalog: real inventory and the crosses your business already documented. The price and the SKU come from your catalog, they are never invented; if a line has no price, it escalates to a person.
- It answers line by line: part, price, stock by branch and that fleet's contract price if they have one.
The trucker's math
💡 The carrier's math: a parked tractor is not a lost sale, it is a load that never gets billed. At a real counter we measured the chat replying in 2 minutes and the price taking a median of 16. In those 14 minutes your people search and key in data instead of selling.
Quoting semi-trucks by hand vs with AI
| By hand | AI quoting tool | |
|---|---|---|
| "The ratchet on the T680" | Three questions over the phone | Asks for the missing data point and quotes |
| Photo of the engine or gearbox plate | Depends on who reads it | It reads and crosses it on its own |
| A 12-line service list | Hours from the best counter | Minutes, line by line |
| Filter cross-references | Three printed catalogs | The ones your catalog documents, instantly |
| Hours | Counter hours | 24/7: tractors roll at night |
How to test it on your operation
Send the quoting tool the last service list a fleet sent you, or a photo of an engine plate somebody asked about this week, and measure how many lines it resolved and how fast. The diesel parts quoting tool guide covers the engine side and quoting for fleets covers contracts and volume. The other vehicle types are in quoting parts by vehicle type.
Engines that go in tractors
The quoting rules for each engine: Cummins X15 · Cummins ISX · Cummins ISM · Detroit DD15 · Detroit DD13 · Detroit Series 60 · Caterpillar C15 · Navistar MaxxForce.
Frequently asked questions
Is the tractor's make and model enough to quote?
No. The chassis brand (Kenworth, Freightliner, International, Volvo) does not define the engine, the transmission or the axles. For the engine you need the serial; for the transmission, the gearbox model; for brakes, the chamber type and the size. The 17-digit VIN covers cab and electrical.
Where are the transmission and engine numbers?
The engine carries its plate with the serial on the block; the Eaton Fuller or Allison gearbox carries its own plate with model and serial. A photo of each plate over WhatsApp is enough for the quoting tool to read it.
Does the quoting tool understand trucking slang?
Yes. It understands trucking words and crosses them to the name your catalog uses. If the ruling data point is missing (slack adjuster splines, driveshaft series, air bag position), it asks for it in a single question.
Does it quote in the middle of the night?
Yes, 24/7. Tractors roll at night and a breakdown does not wait for counter hours: the quote goes out at whatever hour the driver asks for it, with the price and stock from your catalog.