About Ryan’s Diesel Service
Since 2010, Ryan’s Diesel Service has been providing customers with A+ customer service on performance diesel repairs and maintenance in Southeastern Wisconsin. Ryan’s Diesel Service has over a 9000 sqft facility to perform diesel repair and service; stocking many diesel performance products on hand. In addition to online sales, Ryan’s Diesel Service also has an 8-bay service center, with the expertise to handle any service or repair needed on your truck.
Diesel Performance Shop & Truck Repair
The light-duty truck repair: we work on anything from daily drivers to competition vehicles; we can handle any of your truck’s needs. Many repairs include head gaskets, injectors, turbochargers, emissions issues, transmissions, drivetrain, electrical and more.
Our medium and heavy-duty repair: we can service; engine repair/ major overhaul, clutches/transmissions, brakes/hubs, emissions/DEF issues, forced regens, DOTs. While some trucks aren’t driveable we do have a mobile service truck to come onsite to insure your truck will safely make it to our shop for repair.
Engines/transmissions we service include Duramax Diesel, Powerstroke Diesel, Cummins Diesel, PACCAR, Allison Transmission, Eaton/Fuller.
Dealer-level software we have includes GM SPS/TIS2Web, Cummins Insite/Quickserve, JPRO, Allison DOC, Meritor WABCO and more.
When you are searching for the best diesel performance shops near me, look no further than the experts at Ryan’s Diesel.
Custom Diesel Machine and Manufacturing
Ryan’s Diesel Service is no stranger when it comes to the manufacturing of high-end diesel products. Ryan believes all products should be manufactured in-house to maintain high levels of quality control.
We currently have a HAAS VF4 5-axis machining center which runs a fair majority of our products. We also have a HAAS TL-1 lathe.
Turbo balancing is all done in-house on either our West Coast Balancer WCB30 or CWT industries balancer.
In addition to diesel turbos being manufactured in-house, we also offer cylinder head machining for diesel and gas engines. In the summer of 2021, Ryan purchased the remaining machines from a closed local machine shop to bring these services in-house. This means all head gasket jobs done by Ryan’s Diesel Service are completed in-house with zero outsourcing. From being washed in our 220f parts washer, to pressure tested and milled they never leave our building. If you are a local customer you can also bring your cylinder heads into the shop for machining and cleaning.
Testimonials
64 mm turbo I just got installed in the truck sounds amazing and appreciate all the answers I received when I called or messaged. Thank you
Outstanding service contact them on a Saturday afternoon with an incoming snow storm in need of a TCM. they were more than willing and happy to help me out. They... read more had it ready for me and waiting before I got to the shop. Called lot of other shops and dealers and none was willing to help except for Ryans.
Great job cleaning and pressure checking the heads on my lb7. Super nice people, they know their stuff that's for sure
Great guys only wish they would rebuild transmission and send them out with I understand why they don’t but everyone is not dumb and not have their transmission system flush... read more before install
I spoke with Ryan about my truck and the problems it was having as well as additional things I wanted them to look at and he was super helpfull and... read more made sure to address all of my concerns. I left my truck with them and look forward to getting my diagnosis and options to get it fixed. I'll report back with updates.

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