Best 68RFE Transmission Upgrades: 2007-2018 Ram Cummins

If you own a 2007.5-2018 Ram 2500 or 3500 with the 6.7L Cummins, the smartest money you can spend is on 68RFE transmission upgrades — before the factory transmission lets you down. The 68RFE is a strong six-speed automatic at stock power, but the moment you add a tuner, bigger injectors, or a heavy trailer, its overdrive clutch pack and torque converter lockup clutch become the first things to fail. At our Tampa, FL shop we see twisted input shafts and burned overdrive clutches roll in every week on tuned Cummins trucks. This guide breaks down the five best 68RFE upgrades we sell and install, with real specs, line-pressure data, holding power, and pricing so you can match the right kit to your power level and budget.

What Is the 68RFE and Why Does It Fail?

The 68RFE is a six-speed automatic transmission built by Chrysler for 2007.5-2018 Ram 2500 and 3500 trucks equipped with the 6.7L Cummins diesel. It is fully electronically controlled, rear-wheel-drive, and was engineered around the factory engine’s 650 lb-ft of torque. Its gear ratios are 3.231 (1st), 1.837 (2nd), 1.410 (3rd), 1.000 (4th), 0.816 (5th), 0.625 (6th), and 4.444 reverse. From the factory it is rated to tow roughly 10,000-12,000 lb for about 150,000 miles at stock power — a great daily-driver and tow box, but one with a thin margin for modification.

A 68RFE transmission upgrade strengthens the unit’s weakest links so it can survive the extra torque of a tuned Cummins. The most common 68RFE failure is the overdrive clutch pack: the factory uses thin, single-sided 0.034-inch clutches that distort under heat and added torque, which takes the clearance out of spec and burns the overdrive clutch. The second most common failure is the torque converter lockup clutch, which slips and shudders under load, dumping heat and metal debris into the fluid. Underneath both problems is line pressure — the stock 68RFE caps pressure near 160 PSI, which is not enough to clamp the clutches above roughly 400 hp. Push hard enough and the input or output shaft itself will twist or snap. Every upgrade below attacks one or more of these failure points.

How We Picked These 68RFE Upgrades

We chose these five upgrades based on what actually keeps Cummins trucks on the road, not on marketing claims. Every product below fits the 2007.5-2018 Ram 2500/3500 6.7L Cummins, comes from a proven diesel brand (ATS Diesel, BD Diesel, and aFe), and is in stock at NLP Performance. We ranked them by the real-world problem each one solves — line pressure, clutch capacity, converter lockup, and shift quality — and by the power level they support, from a stock-power shift tuner to a 700 hp built transmission. Our recommendations come from installing and servicing these exact parts on customer trucks in Tampa, where towing in Florida heat is the harshest test a 68RFE will ever see.

The 5 Best 68RFE Transmission Upgrades

Below are our top five 68RFE upgrades, ordered from the best all-around value to the strongest full replacement. Pick based on your power goals and how much of the work you want to do yourself.

1. ATS Diesel 68RFE Billet Transmission Upgrade Kit — Best Overall

This kit is our top pick because it solves the 68RFE’s root problem — line pressure — without pulling the transmission. It pairs an ATS billet valve body with the ATS Co-Pilot controller, a 24-pin plug-and-play module that reads boost and throttle position and raises line pressure from the stock 160 PSI up to 270+ PSI using closed-loop control. That extra clamping force keeps the overdrive clutches and converter lockup from slipping under a tune, and the Co-Pilot applies the converter clutch more aggressively to kill shudder. Installed on a healthy core, it reliably supports 600+ hp Cummins builds.

2. BD Diesel Roadmaster 68RFE Transmission & Pro Force Converter — Best Full Replacement

When the factory 68RFE is already cooked — or you are running far past 500 hp — a complete built transmission is the right call. The BD Diesel Roadmaster is a fully remanufactured 68RFE with upgraded clutches and a matched Pro Force triple-disc torque converter, and it is rated to safely hold 700 hp and 1,300 lb-ft. As a daily-driven tow rig it comfortably lives in the 500-700 hp range. Because it ships as a complete unit with the converter, it removes the guesswork of building a core and is the closest thing to a bolt-in solution at this power level.

3. BD Diesel Built-It Stage 4 Master Rebuild Kit — Best for DIY Builders

If you or your builder are rebuilding the 68RFE yourself, this Stage 4 Master Rebuild Kit is the best value way to do it right. It replaces the failure-prone factory friction stack with upgraded clutches and includes the BD ProTect 68 pressure-control kit, which addresses the line-pressure shortfall at the valve body level. At $1,538.50 it costs a fraction of a complete built unit, but it assumes you have the tools, space, and skill to tear down and reassemble the transmission. Note that it does not include a torque converter, so budget for an upgraded converter separately if your power demands one.

4. ATS Diesel 68RFE Performance Valve Body — Best Budget Reliability Fix

For owners who want a reliability upgrade without the full kit price, the ATS Performance Valve Body is the smart entry point at $889.99. It reworks the factory valve body to enable full line pressure, which is what stops the overdrive and converter clutches from slipping on a mildly tuned truck. It pairs naturally with a line-pressure controller down the road, so it is also a logical first step on a staged build. Plan on dropping the transmission pan to install it, and replacing the fluid and filter while you are in there.

5. aFe Power Shift Logic Transmission Module — Best Bolt-On Insurance

At $410, the aFe Shift Logic module is the cheapest meaningful insurance you can add to a stock or lightly tuned 68RFE. It modifies transmission line pressure to firm up shifts, reduce clutch slippage, and lower fluid temperature — all of which extend transmission life. A single button toggles three modes (Stock, Stage 1, Stage 2) so you can dial in shift feel for towing versus daily driving. It will not rescue worn-out clutches, but on a healthy transmission it is the best $410 you can spend to slow the wear that kills these units.

68RFE Upgrade Comparison Chart

Here is how the five 68RFE upgrades stack up by upgrade type, power capacity, and price. Use it to match the right part to your build.

Which 68RFE Upgrade Path Is Right for You?

Match the upgrade to your power level and how you use the truck. For a stock or near-stock truck that you simply want to last, start with the aFe Shift Logic module ($410) and fresh fluid — firmer shifts and lower temps buy you years. For a mildly tuned daily driver under roughly 400-450 hp, the ATS Performance Valve Body ($889.99) restores full line pressure where the factory falls short.

Once you are tuning hard, deleting EGT headroom, and pushing 450-600 hp while keeping the original case, the ATS Billet Upgrade Kit ($3,687.52) is the sweet spot — 270+ PSI of line pressure and aggressive converter lockup are exactly what a tuned Cummins needs. And if the transmission is already slipping, or you have crossed 600 hp, stop patching and install the BD Roadmaster ($5,802.73), a complete 700 hp / 1,300 lb-ft unit. DIYers with the tools and a tired core can rebuild it themselves with the BD Built-It Stage 4 kit ($1,538.50) for the best dollar-per-clutch value of the group.

Supporting Mods That Make Any 68RFE Last Longer

Heat is the 68RFE’s silent killer, and every upgrade above lasts longer when the fluid stays cool and clean. A deep-sump transmission pan is the simplest insurance: the BD Diesel Deep Sump Pan adds about 4.5 quarts of extra capacity (roughly 11 quarts total) in a cast-aluminum housing with a drain plug, dropping fluid temperatures and extending fluid life. Pair it with fresh ATF+4, an upgraded torque converter when your power calls for it, and a service interval you actually keep.