Shop Aisin Parts →
The Aisin AS68RC is the 6-speed automatic Chrysler bolted behind the 6.7L Cummins in Ram 2500/3500 (and the earlier 3500/4500/5500 cab-and-chassis) from roughly 2007 onward, as the heavier-duty alternative to the 68RFE. It is a stout unit, but the torque converter is its recognized weak point. The lockup clutch and the converter internals do not love the combination of diesel torque, towing heat, and long service intervals, and when the converter starts to come apart it can send debris through the whole transmission — which is exactly why you do not ignore the early symptoms.
This page covers what the AS68RC torque converter job costs in 2026, how to recognize a dying converter before it grenades, the labor reality of dropping this transmission, and whether the billet upgrade is worth it.
Symptoms of a Failing AS68RC Torque Converter
- Shudder on lockup — a vibration or rhythmic shake, usually felt at 40-55 mph under light throttle as the converter clutch tries to engage. Often the very first sign.
- Slipping under load, especially towing or on a grade: engine RPM climbs but road speed does not follow.
- Rising transmission temperature beyond normal when towing, because an unlocked or slipping converter dumps heat into the fluid.
- Burnt-smelling, dark ATF and metallic glitter on the pan magnet — converter clutch material breaking down.
- Torque converter clutch (TCC) codes such as P0740 (TCC circuit malfunction), P0741 (TCC stuck off / performance), P0742 (TCC stuck on), and related lockup-slip codes.
- Stalling at stops if the converter clutch sticks applied, or a shudder that worsens as the trans warms up.
A scan tool that reads live TCC slip RPM is the fastest way to confirm it. A healthy locked converter shows near-zero slip; a failing one shows slip creeping up under load. Catch it here and you replace a converter. Ignore it and the debris takes out the pump and clutches too.
Diesel-capable scan tools
The Labor Reality: You Have to Drop the Transmission
This is where AS68RC converter cost separates from a passenger-car job. The torque converter sits between the engine and the transmission, so there is no shortcut — the entire transmission has to come out of the truck to reach it. On a 6.7 Cummins Ram that means:
- Supporting and unbolting a heavy-duty transmission (these units are around 250+ lbs dry, more with fluid) on a transmission jack rated for the weight.
- Disconnecting the transfer case on 4x4 trucks, driveshafts, crossmember, exhaust clearance, cooler lines, wiring, and the flexplate-to-converter bolts.
- Careful reinstallation so the converter is fully seated on the pump before the bellhousing bolts up — get this wrong and you destroy the new converter and the pump on first start.
Book labor to drop and reinstall the AS68RC typically runs 8 to 12 hours depending on 2WD vs 4x4 and how rusty the truck is. At 2026 diesel-shop rates of $150 to $200 an hour, labor alone lands between roughly $1,200 and $2,400. That is the number that shocks people, and it is why most shops recommend doing the converter and a full fluid-and-filter service, and inspecting the transmission, all in the same drop.
2026 Replacement Cost: Total Ranges
| Scope | Parts | Total (parts + labor) |
|---|---|---|
| Stock-replacement converter, shop install | $350 - $700 | $1,600 - $3,000 |
| Billet / upgraded converter, shop install | $700 - $1,400 | $2,200 - $4,000 |
| Converter + reman transmission (if debris spread) | $3,000 - $5,500 | $5,000 - $8,500 |
| DIY converter (you drop the trans) | $350 - $1,400 + fluid | $450 - $1,600 all-in |
The spread is enormous because so much rides on labor and on whether the failing converter already contaminated the rest of the unit. If you catch the shudder early and the fluid is still relatively clean, you get out at the low end. If you drove it until it was slipping badly and the pan is full of metal, you are into a rebuild and the converter is the cheap part of the bill.
The Billet Converter Upgrade
Given that the biggest cost of this job is the labor to get in there, most experienced diesel owners upgrade the converter while the transmission is out rather than reinstalling another stock-style unit that may fail the same way. A billet torque converter uses a forged, single-piece front cover (the "billet" part) instead of a stamped/welded one, plus an upgraded, larger-capacity lockup clutch and often a higher stall tuned for the truck's use.
Worth it if: you tow heavy, run a tuner or added power, or simply do not want to pay 8-12 hours of labor twice. The upgraded lockup clutch is far more resistant to the shudder-and-slip failure that killed the original.
Skip it if: the truck is bone-stock, lightly used, and you just want it back to factory at the lowest parts cost — a quality reman stock converter is fine for that duty.
AS68RC torque converters
Parts and Fluid You'll Need
- The torque converter (stock-replacement or billet) matched to the AS68RC.
- Transmission filter and pan gasket kit — always replace while the unit is out and drained.
- The correct ATF. The AS68RC calls for a specific Aisin-spec fluid (a Ram/Mopar ATF+4-superseding spec on these applications). Verify the exact spec for your year and use the correct fluid; a full converter-and-trans fill is a large volume, often 15-18+ quarts once the empty converter is filled.
- A transmission jack rated for the unit's weight if you are doing it yourself — do not attempt this on an underrated jack.
AS68RC filter and gasket kits
AS68RC-spec transmission fluid
DIY vs Diesel Shop
This is not a beginner job. It is a heavy transmission over your head, on a jack, with a transfer case and driveshafts to manage on a 4x4. That said, a well-equipped DIYer with a lift, a proper transmission jack, and the patience to seat the converter correctly can do it and save the four-figure labor charge. The single most important step is verifying the converter is fully engaged with the pump before mating the bellhousing — measure the depth per the service data and confirm it turns freely with the trans. A converter that is not fully seated will destroy the pump the instant you start the engine.
Hand it to a diesel shop if you do not have the equipment to safely support the transmission, if the fluid came out full of metal (you likely need more than a converter), or if the truck is heavily rusted underneath. Whatever route you take, replace the fluid and filter, and prime and fill the new converter before install so you are not running it dry on startup.
Need a Converter, Filter Kit, or Fluid? Ships Same-Day
Gearbox Insider stocks AS68RC torque converters, filter and gasket kits, and the correct spec ATF so you can do this heavy job once. Same-day ship before 2pm Eastern.
Shop Gearbox Insider →FAQ
Can I keep driving with converter shudder?
Not for long. Early shudder is your warning window to fix it as a converter-only job. Keep driving and the clutch material sheds into the fluid, contaminates the whole transmission, and turns a converter replacement into a full rebuild.
Should I flush the transmission cooler when I replace the converter?
Absolutely. A failing converter sends debris into the cooler and lines. If you install a fresh converter and leave contaminated fluid trapped in the cooler, it circulates right back into the new parts. Flush the cooler and lines every time.
Is the AS68RC converter the same as a 68RFE?
No. The AS68RC is the Aisin-built heavy-duty unit and uses its own converter; do not cross-shop 68RFE parts. Match parts to the AS68RC specifically.
How long should the new converter last?
A quality billet converter with an upgraded lockup clutch, clean fluid, and a properly flushed cooler should outlast the original by a wide margin, especially on a towing truck. Fluid maintenance is what determines its real lifespan.