Your Diesel Deserves More Than a Guess.
Precision diagnostics. Honest repairs. No shortcuts — just mechanics who actually understand what makes your diesel run right.
Diesel Work Done Right the First Time
From routine maintenance to complex engine overhauls, we bring the expertise your diesel deserves — every single visit.
Engine Diagnostics
Advanced diagnostic tools to pinpoint exactly what's wrong — no guesswork, no unnecessary parts, no surprise bills.
Engine Repair & Rebuild
From minor fixes to full rebuilds — we restore your diesel to peak performance with quality parts and careful craftsmanship.
Performance Tuning
Unlock your diesel's true potential with custom tuning that improves power, torque, and fuel efficiency — safely and reliably.
Preventative Maintenance
Stay ahead of problems before they strand you. Scheduled service keeps your diesel running smooth and your downtime to zero.
Fuel System Service
Injectors, pumps, lines — we diagnose and repair fuel system issues that cause rough idles, poor mileage, and lost power.
Commercial Fleet Service
Keep your fleet on the road. We service Class 4–8 diesel trucks with the speed and thoroughness your business depends on.
Built on Hard Work, Kept Running on Trust
Vonderhaar Diesel Performance isn't a franchise or a chain. We're a local shop in New Paris, Ohio, built on the belief that diesel engines — whether in a pickup, a semi, or farm equipment — deserve attention from people who actually understand them.
We've spent years learning what makes these machines tick, and more importantly, what makes them fail. That experience shows up in every repair we do: thorough diagnostics, honest assessments, and work that stands the test of the road.
The Difference Is in the Details
There are plenty of places to get a diesel fixed. Here's why your neighbors keep coming back to us.
We Show Up on Time
Your diesel is your livelihood. We respect that by getting you back on the road fast — without cutting corners.
Real People, Real Answers
No call centers or automated scripts. Talk to someone who knows your truck and can explain what's actually going on.
Quality Parts, Every Time
We use reputable parts from trusted suppliers. If it's not good enough for our own trucks, it's not good enough for yours.
Straight-Talk Pricing
You'll know the cost before we start. No hidden fees, no "while we're at it" surprises — just honest, upfront pricing.
Don't Let a Diesel Problem Put You on the Sidelines
Whether it's a check engine light, a rough idle, or a breakdown you've been putting off — give us a call. We'll figure it out together.
Let's Talk About Your Diesel
Have a question or need to schedule service? Reach out — we're here to help.
Send Us a Message
Tell us what you need and we'll get back to you as soon as possible.
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