Diesel Repairs & More in Lone Rock, WI
GJ’s Service in Lone Rock, WI, offers expert diesel diagnostics, brakes, oil changes, engine work, and more. Founded by truckers for truckers, we deliver honest, high-quality repairs on all makes and models. Call 608-583-2200 to schedule service you can trust.

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About Us
Gordy Poad-owner started trucking in 1976( P&p carriers/ P&p grain) driving and wrenching himself and grew his trucking company to the point he needed his own mechanics to keep up the maintenance on his trucks and trailers. In 1990 the shop(Gj's service) started taking on outside work and has not looked back since, taking on any outside work while also still managing Gordy's fleet to this day. Gordy's mechanics also help maintain his farm( Triple p farm) equipment
Diesel Services in Lone Rock, WI
Diesel-powered equipment is built to work hard—and that’s exactly how we treat every service call here at GJ’s Service. From routine maintenance to complex diagnostics and repairs, we provide thorough diesel services designed to keep your truck performing the way it should.
Parts
Visit our store to browse available parts

News & Articles
Here, you'll find regular articles covering a wide range of topics related to diesel repair, maintenance, and troubleshooting.
Don't Take our word for it.
Read Customer Testimonials.
"Awesome crew! Had a tire leaking 1 of the mechanics was waiting for me when I got there and went straight to work on it. If I have a problem in that area again I know right where I'm going."
"Nicest friendliest hard-working bunch of folks I ever met. They got me in and out so fast. Highly recommend coming here if you need anything for your trucking business."
"Awesome shop, I'm from out of town and needed help with a check engine light. They got me in right this morning at opening checked it out for. Thanks for the help guys"
Trucks we specialize in
Frequently Asked Questions
Find detailed responses to some of our most frequently asked questions.
We are located at 420 East Forest Street, near the intersection of US Highway 14 and County Road JJ in Lone Rock, WI. In addition to serving Lone Rock, we also assist customers in Spring Green, WI; Gotham, WI; Madison, WI; Wisconsin Dells, WI; Lancaster, WI; Dodgeville, WI; Platteville, WI; Monroe, WI; and Richland Center, WI. If you’re within 50 miles, we’re your trusted local shop for diesel work.
Diesel preventive maintenance should typically be scheduled every 10,000–15,000 miles or according to your manufacturer’s guidelines. This ensures that vital systems like the engine, cooling, and fuel system are working at peak efficiency. Regular checks also prevent costly breakdowns and extend the life of your vehicle.
A knocking sound often points to abnormal combustion or worn internal components. It could be caused by faulty fuel injectors, improper fuel timing, or low-quality fuel. It’s important to have it inspected promptly, as continued operation can cause severe damage.
Common signs include grinding noises, longer stopping distances, or a soft or spongy pedal. You may also see the brake warning light come on or feel vibrations when braking. These issues indicate that components like brake shoes or air lines may need attention.
Contact Us
Let us know what is going on with your vehicle, and we will get back to you soon with a quote.