Transmission fluid service
Proper drain and fill, or fluid exchange where the manufacturer calls for it. Correct fluid spec every time.
Transmissions
Transmission Repair and Service in Boulder, CO
Slipping, hard shifting, or transmission warning light? We diagnose, service, and repair automatic, manual, and CVT transmissions.
Full transmission service for automatic, manual, and CVT vehicles. Fluid service done the right way for the right transmissions, slip and shift diagnosis, valve body and solenoid work, manual clutch service, and rebuild or replacement coordination when the case calls for it.
Every transmission, the right way.
Not every transmission should be flushed. Not every shift problem is internal. We diagnose before we recommend.
Slip and shift diagnosis
Live data, road test, and pressure testing to isolate the cause before parts get involved.
Valve body service
Cleaning, repair, or replacement when the data points to hydraulic control problems.
Solenoid replacement
Shift and pressure control solenoids replaced individually when fault data isolates them.
CVT service
CVT-specific fluids, belts, and adaptations. Done by techs who know CVTs are not regular automatics.
Manual clutch and flywheel
Clutch replacement, flywheel resurfacing or replacement, pilot bearing, and hydraulic service.
Rebuild and replacement coordination
When the transmission needs to come out, we manage the job with trusted rebuild partners or factory replacements.
How to tell something is wrong.
If you notice any of the following, do not wait. Small issues become expensive ones quickly.
- Slipping under load or between shifts
- Hard, harsh, or delayed shifts
- Shudder or vibration during light acceleration
- Visible transmission fluid leak under the vehicle
- Transmission warning light on the dash
- Burning smell from the transmission
- Gear hunting or constant downshifts on hills
How we work a transmission.
Diagnostic scan and live data
Codes, freeze frame, and live transmission data captured before any parts conversation.
Fluid condition check
Color, smell, and metal content. The fluid tells the story of what is happening internally.
Isolate internal vs external
Sometimes it is a wiring fault, a sensor, or an engine issue masquerading as a transmission problem.
Repair with quality parts
OEM-spec or premium aftermarket. Proper torque, fresh seals, no shortcuts.
Verify under load
Road test under real conditions. Highway, hills, stop-and-go. Confirm the fix holds.
Why transmission work belongs here.
We do not flush transmissions that should not be flushed
Some transmissions need a drain and fill. Others a flush. We follow the manufacturer, not a service menu.
Diagnose before we sell service
A fluid service does not fix a slipping transmission. We tell you what is actually wrong, then what to do.
Photo documentation
You see the burnt fluid, the metal on the magnet, the leak point. No mystery, no guessing.
Warranty backed
Three-year, thirty-six-thousand-mile NAPA warranty on qualifying transmission repairs.
Mile-high roads ask more of every vehicle.
Boulder vehicles work harder. Thinner air, hard freezes, dust, sun, and steep grades all wear parts faster than the manufacturer schedules assume. We tune our service intervals to how your vehicle actually lives at altitude.
Altitude
Lean-running engines, harder-working turbos, and drivetrains that climb every commute.
Freeze cycles
Repeated thaw and refreeze chews through seals, hoses, batteries, and brake hardware.
UV and dust
High-altitude sun and grit accelerate paint, plastics, glass, and intake fouling.
Frequently Asked Questions
It depends on the transmission. Some manufacturers call for a fluid exchange at specific intervals. Others specify drain and fill only. A flush on a high-mileage transmission that has never been serviced can sometimes do more harm than good. We check your specific vehicle's spec and condition before we recommend anything.
You may also need
Oil Change Service
Pair with an oil change for one streamlined visit.
Drivetrain
Differentials, axles, and transfer cases work with the transmission.
Engine Diagnostics
Engine performance issues sometimes show up as shift problems.
Computer Diagnostics
TCM scan and adaptations are part of modern transmission work.
Boulder talks. We listen.
“These guys are honest, transparent, and clearly know what they are doing. They walked me through everything with photos before doing the work.”
Sarah K.
2019 Subaru Outback
“Best shop in Boulder. Free loaner, fair pricing, and they actually care about doing the job right. Will not take my truck anywhere else.”
Marcus T.
2017 Toyota 4Runner
“I am picky about who touches my EV. Legacy was the only shop locally that I trusted with the work, and they delivered.”
Priya N.
2022 Tesla Model Y
“These guys are honest, transparent, and clearly know what they are doing. They walked me through everything with photos before doing the work.”
Sarah K.
2019 Subaru Outback
“Best shop in Boulder. Free loaner, fair pricing, and they actually care about doing the job right. Will not take my truck anywhere else.”
Marcus T.
2017 Toyota 4Runner
“I am picky about who touches my EV. Legacy was the only shop locally that I trusted with the work, and they delivered.”
Priya N.
2022 Tesla Model Y
Ready to Book?
Schedule your transmission repair and service today.
Free loaner vehicles for qualifying repairs. Photo and video documentation on every job. Three-year, 36,000-mile NAPA warranty.