Transmission Diagnostics & Repair in Louisville | Auto & Heavy Duty Transmission
Slipping, hard shifts, sensor faults, fluid issues, and electronic transmission diagnostics for all vehicles.
Common Transmission Problems We Diagnose
| Problem | What You'll Notice | What Could Be Wrong |
|---|---|---|
| Slipping | Engine revs but vehicle doesn't accelerate properly | Low fluid, worn clutches, torque converter failure, valve body issue |
| Delayed engagement | Pause before transmission engages when shifting to Drive or Reverse | Low pressure, worn seals, solenoid failure |
| Hard shifting | Abrupt, jerky shifts between gears | Solenoid stuck, valve body contamination, TCM calibration issue |
| Transmission warning light | Check engine light or transmission temp light on | Electronic fault — needs code scan + live data |
| Torque converter shudder | Vibration at highway speeds, especially under light load | Torque converter failing, low fluid, TCC solenoid issue |
| Fluid leaks | Red fluid under the vehicle | Pan gasket, cooler line, front/rear seal |
| No reverse | Vehicle moves forward but won't reverse | Valve body failure, worn reverse clutch, low pressure |
| Burning smell | Sharp odor, especially after hard driving | Overheating, burnt fluid, worn clutches |
Bring the vehicle in when symptoms start. Early diagnosis gives you more repair options and helps prevent internal damage.
Our Transmission Diagnostic Process
Every transmission service starts with testing, not parts replacement:
- Code Scan & Live Data — We read transmission codes and monitor gear ratios, solenoid commands, pressure control values, temperature, and TCC lock-up.
- Fluid Level & Condition Check — We inspect level, color, smell, and contamination. Burnt fluid or metal particles indicate internal wear.
- Line Pressure Test — We compare actual hydraulic pressure against target pressure to check the pump, valve body, and seals.
- Solenoid Resistance Test — We test shift solenoids and pressure control solenoids for resistance and function.
- Torque Converter Lock-Up Test — We verify TCC engagement and release to separate converter issues from valve body faults.
- Road Test — We reproduce the symptom while monitoring live transmission data.
- Diagnostic Report — You get the cause, repair recommendation, and cost before work begins.
Transmission Repair & Rebuild Services
After diagnosis, we explain the repair options clearly.
Minor Repairs
Not every transmission problem needs a rebuild. We perform:
- Solenoid pack replacement — For hard shifting, shift timing issues, and electrical solenoid faults.
- Valve body replacement or rebuild — For worn bores, stuck valves, or contamination.
- Torque converter replacement — For TCC or converter failure without a full rebuild.
- Seal and gasket replacement — For leaks or delayed engagement caused by worn seals.
- TCM reprogramming or replacement — For software-related shifting issues. See our ECM programming page for details.
Full Rebuild
A rebuild is the right repair when internal wear is confirmed: burnt clutches, worn drums, failed planetary gears, or heavy contamination.
What a rebuild includes:
- Complete disassembly and inspection
- Replacement of clutches, steels, seals, and gaskets
- Valve body inspection and rebuild if needed
- Torque converter replacement when recommended
- New filter and fluid
- TCM calibration and adaptive learning reset
We rebuild transmissions from: Passenger cars, light trucks, heavy-duty trucks, and semi trucks.
Transmission Replacement
Replacement may make more sense when the case is damaged, rebuild cost is too high, or turnaround time matters.
Options include:
- New OEM transmission — Factory new, full warranty
- Remanufactured transmission — Professionally rebuilt with balanced cost and quality
- Used / low-mileage transmission — Budget option with limited warranty
We help you compare cost, warranty, vehicle value, and how long you plan to keep the vehicle.
Heavy Duty & Semi Truck Transmission
Heavy-duty transmission work requires the right tools and platform knowledge.
Allison Transmissions — Found in Ram 3500 (68RFE, Aisin AS69RC), GMC/Chevy HD trucks, and commercial vehicles. We diagnose and repair:
- Allison 1000 / 2000 series
- Torque converter lock-up issues
- Shift quality complaints
- TCM communication problems
Aisin Transmissions — The Aisin AS69RC (Ram 3500 2019+) is a heavy-duty 6-speed with specific diagnostic requirements.
Eaton Fuller 10-Speed / 13-Speed / 18-Speed — Manual and automated manual transmissions found in Class 8 trucks. We diagnose and repair:
- Shift fork wear
- Synchronizer failure
- Air system issues
- Clutch actuation problems
Note: Heavy-duty transmission service is TRANSMISSION service, not fleet management. Fleet maintenance clients will find our transmission services linked from the fleet page, but all transmission work is performed and quoted from this page.
Frequently Asked Questions
How do I know if my transmission is failing?
Common warning signs include slipping, delayed engagement, hard shifts, whining, clunking, grinding, fluid leaks, or a burning smell. Schedule a diagnostic early to avoid more internal damage.
Can you rebuild my transmission, or do I need a replacement?
It depends on the damage. Most transmissions can be rebuilt, but replacement may be better if the housing is damaged, rebuild cost is too high, or you need the vehicle back faster.
How long does a transmission rebuild take?
Most rebuilds take 2-5 business days depending on parts and transmission type. Fleet vehicles can receive priority scheduling to reduce downtime.
Do you work on semi truck transmissions?
Yes. We service Eaton Fuller manual and automated manual transmissions, plus heavy-duty automatic transmissions used in commercial trucks.
Will a tune-up fix my transmission problems?
A transmission tune-up usually means fluid and filter service. It may help minor shift concerns, but it will not fix worn clutches, torque converter failure, or internal mechanical damage.
How much does a transmission diagnostic cost?
Contact us for current diagnostic fees.. This covers the diagnostic process and is typically applied to the repair if you authorize the work with us.