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Find the failure first · Fontana, CA

Heavy Equipment Diagnostics

The most expensive repair is the wrong one. Our diagnostic work exists to prevent it: a structured teardown and inspection of the failed system, documented with photos and video, so the quote you approve is for the failure you actually have — not the one somebody guessed at over the phone.

Find the failure first · Fontana, CA

What a real diagnostic visit looks like

We start with the symptoms as the operator experienced them — the noise, the leak, the power loss, when it happens and when it does not. Then the machine or component is disassembled far enough to see the failure directly: wear patterns, scored surfaces, contamination, cracked housings, damaged gear teeth.

You get the findings the way we found them: photos, video, and a plain-language explanation of what failed, why it likely failed, and what the repair options are — from targeted repair to full rebuild — each with its own written quote.

Worn heavy equipment attachment inspected during diagnostics at LA Trucks and TractorsHeavy Equipment Diagnostics · Fontana, CA

Symptoms we chase down every week

Hydraulic drift and weak lift, overheating, grinding or whining from gearboxes and final drives, power loss under load, hard starting and no-start diesels, transmission slip, metal in the oil, and the mysterious intermittent fault that only appears under load. Intermittents are where documented, methodical diagnosis pays for itself.

Diagnostics are part of our standard process — inspection and the quote are free. Regular hours Monday–Friday 6 AM–5 PM; rush line 24 hours, every day of the year.

  • Engine and drivetrain fault isolation
  • Hydraulic pressure and contamination checks
  • Gearbox and final-drive failure analysis
  • Electrical-starting and charging faults
  • Pre-purchase and pre-sale machine evaluation

Our 8-step repair process

A clear path from the first call to a tested component or machine returned to work.

01

Pick-up

Coordinate free equipment or component pick-up when applicable.

02

Inspection

Disassemble and evaluate the complete failure.

03

Photos & video

Document condition and findings for a clear repair conversation.

04

Repair quote

Define the recommended work and quote before proceeding.

05

Approval

Confirm scope, urgency and the practical path forward.

06

Manufacturing

Machine, weld, rebuild or reverse engineer required components.

07

Testing

Verify operation and workmanship before release.

08

Shipment

Return the completed component or equipment to service.

Frequently asked questions

Does diagnosis cost anything?

Inspection and the repair quote are free. You approve the scope before any billable repair work proceeds.

What do I get from the inspection?

Photos and video of the failure, a plain explanation of what we found, and written options with quotes.

Can you diagnose a machine that only fails sometimes?

Yes — bring us the pattern: when it happens, under what load, hot or cold. Intermittent faults are a diagnosis specialty, not a nuisance.

Emergency breakdown? Call the 24-hour rush line.

(949) 400-2937

Schedule service or open a repair order

Request a service call.

Include the make, model, symptoms, location, urgency and preferred service time. Your details open in a text to John so you can review them before sending.

Schedule Service / Repair Order