Diesel & truck repair · Arlington, WA · Diesel work since 1985
Your diesel runs because somebody here knows it cold.
Full-service diesel and truck repair in Arlington — diagnostics, engine, transmission, brakes and exhaust. We tell you why a repair is needed, not just what it costs, and we back the work.
4.8★ across 221 reviews · 12-month / 24,000-mile warranty
- Since 1985diesel-industry experience behind the shop
- 4.8★ / 221verified reviews on SureCritic
- 12 mo / 24kwarranty on repair work
- BPD InstallerBullet Proof Diesel Preferred Installer in WA
What we take in
The work order
Bay 01
Ten lines of diesel and truck work, run the way a shop writes them up — plain scope, no padding. Tell us which one brought you in.
Diesel engine service
Performance checks, engine repair and replacement, fuel injection, cooling and radiator, belts and hoses.
Bullet Proof Diesel upgrades
Preferred Installer of Bullet Proof Diesel in Washington State — upgrades that take out the common failure points and extend engine life.
Transmission service
Repair, overhaul and preventative maintenance by techs who work diesel drivetrains every day.
Brakes & suspension
Brake repair and replacement, wheel alignment, struts, shocks and suspension work.
Exhaust & muffler
Exhaust repair, muffler repair and replacement, and tailpipe work.
Electrical service
Alternators and starters, lighting, power locks and windows, and full electrical diagnostics.
Heating & air conditioning
A/C and heater repair, compressor replacement, and climate-control diagnostics.
Fleet services
Preventative maintenance, brake service, engine diagnostics and emergency repairs to keep commercial vehicles road-ready.
Towing & roadside
Local towing and roadside assistance throughout Snohomish County.
Oil & routine maintenance
30k/60k/90k/120k scheduled service, oil changes, filters, tune-ups and multi-point inspections.
What sets the shop apart
One of the only Bullet Proof Diesel Preferred Installers in Washington.
Bullet Proof Diesel upgrades go after the parts that take a hard-worked diesel out of service — the places a stock engine fails first — and replace them before they strand you. In Washington State, the shops approved to install them are few, and The Diesel Doctor is one of them.
It is the kind of work that pays back over years on a truck you plan to keep, and every repair we do is backed in writing.
12 mo / 24kwarranty on repair work, in writing
Who you are handing the keys to
A diesel shop with roots that go back to 1985.
The Diesel Doctor draws on diesel-industry experience going back to 1985, working out of Arlington in the Cascade foothills and farmland north of Seattle. Owner Mark Upthegrove runs the shop the way the trade used to be run: plain language, honest estimates, and the job done when it was said it would be done.
The crew — Mark, Larry and the techs alongside them — take the time to explain why a repair is needed, not just what it costs. We pride ourselves on educating our customers, and we think that is what has earned us a loyal, friendly family of customers. We love what we do, and that basic fact fuels the business.
— Mark Upthegrove, owner
- BBB Accredited · A+ rating
- ASE Certified technicians
- AAA · AC Delco · Bosch · NAPA
- Family owned & operated
In the bay
The trucks that come through
Our own shop — diesel pickups and duallies up on the lifts, semis and fleet rigs in for work, and our tow truck out on the road.
Silverado up on the lift, hood open 
Ram dually in for driveline work 
Semi tractor opened up for the engine 
A full shop — fleet, trucks and an F-350 
Our flatbed, out on a Snohomish County call
What customers say
In their own words
Great business. They do what they say when they say it will be done and for the quoted amount. Wish more businesses were like that
We were in a big hurry late for a trip the crew at diesel doctor, got right after our problem and had us on our way the next day, highly recommend them for any diesel work!
Henry M. Larry called me to tell me it was done at around 11:30! The Diesel Doctor saved the day.
Travis M. Had my truck in for some issues I couldn’t figure out, Larry and the crew had my truck back to me by the afternoon with the issue resolved, my first experience with the Diesel Dr and it was a good one.
John M.
Before you call
The things people ask first
Do you service gas-powered vehicles as well?
We specialise in diesel and truck repair, but our service list — brakes, electrical, A/C, exhaust and routine maintenance — applies to both diesel and gas-powered trucks. Call and we will tell you whether yours is something we take.
Do you offer a warranty on repairs?
Yes. We back our repair work with a 12-month / 24,000-mile warranty.
Do you offer fleet services?
Yes. We handle fleet preventative maintenance, brake service, engine diagnostics and emergency repairs to keep commercial vehicles road-ready.
Do you offer towing?
Yes. Local towing and roadside assistance is available throughout Snohomish County.
Where we work
Arlington & Snohomish County.
We are on 67th Avenue NE in Arlington, in the Cascade foothills north of Seattle, and we work on trucks from across the county.
Get in touch
Bring us the truck
Call the shop or send an email and you reach the people who do the work. We will talk through what is going on before anything is scheduled.
Opening hours
- Monday – Friday
- 8:00 AM – 5:00 PM
- Saturday – Sunday
- Closed
Waiting on your truck? There is free WiFi and complimentary coffee and snacks in the shop.