Truck Transmission & Clutch Repair — Concord, NC
A Class 8 transmission isn't something you want to fail on I-85 during the evening rush. CTR Repair in Concord has been rebuilding, overhauling, and diagnosing heavy-duty manual, automated manual, and automatic transmissions for Cabarrus County operators for more than 30 years. We work on Eaton Fuller manual and UltraShift, Allison 1000 through 4500 series, Volvo I-Shift, Freightliner DT12, and older Mack and Spicer units. Our shop sits at 2931 Armentrout Dr, directly off I-85 Exit 58 in Concord — right where most Cabarrus-based trucks are already passing.
Why Concord Operators Trust CTR for Transmission Work
Heavy-duty transmission repair requires OEM scan tools, brand-specific knowledge, and a shop that's done hundreds of rebuilds. CTR provides all three from our Concord shop at 2931 Armentrout Dr, right off I-85 Exit 58.
Every Major Brand, All in One Shop
Eaton Fuller, Allison, Volvo I-Shift, Freightliner DT12, older Mack T2000 / T310, Spicer — we work on all of them. You don't need one shop for your Peterbilt and a different shop for your Freightliner Cascadia.
OEM Scan Tools for Automated Units
Modern automated manual and automatic transmissions are computer-controlled. We use Eaton ServiceRanger, Allison DOC, Volvo VODIA, and Detroit DDDL to read codes, command tests, run clutch calibrations, and update software.
In-House Rebuilds
We do many transmission rebuilds in-house with OEM rebuild kits, proper bearing pre-loads, and torque specs. Major gear set replacements and case repairs are coordinated with specialty vendors when needed.
Clutch Jobs with Proper Alignment
Heavy-duty clutches need proper alignment and a clean pilot and input shaft. We pull the transmission, inspect the bellhousing alignment, replace the clutch with OEM or Eaton/Haldex components, adjust linkage, and bleed hydraulics (on hydraulic units).
Concord-Based, Known to Cabarrus Fleets
We've worked on transmissions from dozens of Cabarrus County fleets over three decades. Aggregate haulers, concrete mixers, waste trucks, race-industry transporters, regional freight, and owner-operators all come to us.
Transmission Services at Our Concord Shop
From Eaton Fuller manual rebuilds to Allison automatic overhauls, Volvo I-Shift diagnostics, and complete clutch replacement — CTR handles every major heavy-duty transmission brand and type at our Concord location.
9-, 10-, 13-, 15-, and 18-speed Eaton Fuller manual transmissions — the workhorse of the heavy-duty industry. We handle complete rebuilds, input shaft replacement, main shaft and countershaft work, synchronizer replacement, range and splitter repair, and case inspection. We use OEM Eaton rebuild kits.
Complete 9/10/13/15/18-speed Fuller manual rebuilds
Input shaft, main shaft, and countershaft replacement
Synchronizer replacement and range/splitter repair
Case inspection and bearing pre-load verification
OEM Eaton rebuild kits used on all rebuilds
Eaton's automated manual transmissions (AMTs) are mechanically similar to Fuller manuals but add electronic clutch actuators and shift motors. We diagnose electronic faults with ServiceRanger, replace actuators, calibrate clutch tables, and rebuild the gear box when needed.
ServiceRanger diagnostics for electronic fault codes
Clutch actuator and shift motor replacement
Clutch table calibration and software updates
Gear box rebuild when mechanical failure is confirmed
Cummins-Eaton SmartAdvantage integrated powertrain diagnostics
Allison automatics are widely used on ready-mix, vocational, airport ground support, and bus chassis. We service Allison TES fluid changes, filter replacement, valve body service, and complete rebuilds. We run Allison DOC for diagnostic and programming work.
Allison TES fluid changes and filter replacement
Valve body service and solenoid replacement
Complete Allison 1000-4500 series rebuilds
Allison DOC diagnostic and programming
Torque converter inspection and replacement
Volvo's AMT is standard on most modern VNL and VNR trucks. We diagnose I-Shift faults with VODIA, perform clutch and actuator service, run software updates, and rebuild the gear box when required.
VODIA diagnostic software for I-Shift fault codes
Clutch and actuator service and replacement
Software updates and parameter programming
Gear box rebuild for mechanical failures
Shift quality calibration and optimization
Detroit's DT12 AMT (found in Cascadia) shares architecture with the Mercedes PowerShift. We diagnose with DDDL/DLA, service the hydraulic actuation system, and handle clutch replacement and gear-box rebuilds.
DDDL/DLA diagnostics for DT12 fault codes
Hydraulic actuation system service and repair
Clutch replacement with proper calibration
Gear box rebuild and bearing replacement
Mercedes PowerShift architecture expertise
Older Mack transmissions (mDrive and the legacy manual T-series) are still common in aggregate fleets. We have the knowledge and parts sources to rebuild them properly.
Mack mDrive AMT diagnostics and service
Legacy T-series manual transmission rebuilds
Parts sourcing for discontinued Mack transmission components
Aggregate fleet and vocational truck specialists
Older 9- and 10-speed Fuller and Spicer transmissions from legacy fleet equipment still need service. We have the tools and experience.
Legacy 9- and 10-speed Fuller rebuilds
Spicer transmission overhaul and repair
Bearing, synchronizer, and gear set replacement
Vendor relationships for hard-to-find legacy parts
Heavy-duty 14", 15.5", 2-plate, and 15.5" 2-plate ceramic clutches from Eaton, Haldex, and other suppliers. We install with proper alignment, adjustment, and testing. Hydraulic release bearings and mechanical linkage both supported.
14" and 15.5" single and 2-plate clutch replacement
Ceramic and organic clutch disc options
Eaton, Haldex, and aftermarket supplier parts
Bellhousing alignment verification
Hydraulic release bearing and mechanical linkage service
Pilot bearing and input shaft inspection
Worn clutch brakes, sticky shifters, bent shift towers, and loose linkage components — we diagnose and repair the symptoms that waste your time and wear out drivers.
Clutch brake inspection and replacement
Shift tower repair and adjustment
Linkage component inspection and tightening
Shifter cable and rod replacement
Driver complaint diagnosis and resolution
Vibration, thunk, or binding in the driveline? We inspect U-joints, slip yokes, center bearings, and driveshafts for wear, replace components, and balance driveshafts for smoother operation.
U-joint inspection and replacement
Slip yoke and center bearing service
Driveshaft inspection for wear and damage
Driveshaft balancing for vibration elimination
Complete driveline diagnosis for noise and binding
Common Transmission Symptoms
If your truck is showing any of these symptoms, don't wait for a complete failure on the highway. Call CTR at (704) 786-0132 for a transmission diagnostic.
Hard shifting or grinding between gears
Automated manual stuck in a gear, dropping out of gear, or refusing to shift
Allison slipping, harsh shifting, or flaring
Burning smell or metal shavings in fluid
Driveline vibration at highway speeds
Clutch slipping under load
Clutch pedal going to the floor or spongy
Check engine / transmission warning lights
Transmission whine or bearing noise
Transmission Repair Cost Reference
Rebuild pricing varies significantly by model, core condition, and parts availability. We always provide a written estimate before work begins.
| Service | Typical Range |
|---|---|
| Transmission Diagnostic | $175 – $350 |
| Clutch Replacement (14"/15.5", single or 2-plate) | $2,500 – $5,500 |
| Eaton Fuller 10/13/18-Speed Rebuild | $6,000 – $12,000 |
| Eaton UltraShift Rebuild with Calibration | $8,000 – $15,000 |
| Allison 3000/4000/4500 Rebuild | $7,000 – $15,000+ |
| Volvo I-Shift or DT12 Clutch + Actuator | $3,500 – $7,500 |
| Driveshaft U-Joint Replacement | $250 – $700 each |
| Driveshaft Balance | $250 – $500 |
Rebuild vs. Replace: Many transmission problems are sensor, actuator, or clutch issues — not full rebuilds. A proper diagnostic with OEM scan tools often reveals a $500-$3,000 repair instead of a $10,000+ rebuild. CTR always diagnoses first.
Serving Cabarrus County & the I-85 Corridor
CTR Heavy Duty is located at 2931 Armentrout Drive in Concord, NC — directly off I-85 at Exit 58. Aggregate haulers, concrete mixers, waste trucks, race-industry transporters, regional freight operators, and independent owner-operators bring their transmission work here.
Frequently Asked Questions
Rebuilds require pulling the transmission. Clutch jobs also require removal. Some sensor and actuator work can be done with the transmission in place.
Typical Class 8 transmission rebuild runs 5-10 business days depending on core inspection findings, parts availability, and shop load. We set realistic timelines up front.
Yes. Most rebuilds carry a 12-month / unlimited-mile warranty on parts and workmanship.
If you're broken down on I-85 and near Concord, call (704) 786-0132. We coordinate towing and get the truck in as fast as possible.
Hard shifting on Allisons is often a valve body or programming issue, but can also come from low fluid, failing clutches, or electrical faults. We'll diagnose with Allison DOC.
Probably not. I-Shift faults are frequently clutch position sensor, air supply, or actuator issues — much less expensive than a full rebuild. We diagnose with VODIA before assuming the worst.
Yes. mDrive is based on Volvo I-Shift architecture. We service and diagnose them the same way.
Yes, if parts are available. Some older rebuild kits are hard to source, but we maintain vendor relationships for legacy parts.
Schedule Transmission Service Today
Whether it's a clutch replacement, a full Eaton rebuild, or an I-Shift that won't shift — CTR has the tools, the parts sources, and the experience to get it done right. Call now or drive in to our Concord shop.