What Ram Truck Owners Need to Know

If you drive a Dodge Ram 1500, you’re probably familiar with the smooth-shifting 8-speed automatic transmission, formally known as the ZF 8HP70. Used widely across Ram trucks from 2013 all the way to the latest 2025 models, this transmission is praised for its performance and efficiency.

But while it’s a solid unit, it’s not without issues.

At National Transmission, we’ve seen a growing number of Dodge Ram trucks in the shop with 8-speed transmission problems. In this article, we’ll break down the most common transmission failures, what causes them, and how to fix them before they lead to a complete rebuild.

1. A Clutch Pressure Plate Failure

One of the most common failures in the 8-speed Ram transmission is the A clutch pressure plate – a thin, stamped steel plate that’s prone to bending or breaking under pressure.

What’s going wrong?
When the A clutch engages, this pressure plate flexes slightly. Over time, repeated stress causes the plate to crack or break entirely. It’s a design flaw that’s shown up in trucks from 2013 onward.

The fix?
Aftermarket transmission parts manufacturers – like Sonnax – are already working on a heavier-duty pressure plate designed to eliminate this failure point. At National Transmission, we’ll be among the first to upgrade to this stronger component as soon as it’s released.

2. E Clutch Hub Spline Failure

The E clutch hub plays a crucial role in driving the ring gear in the 8-speed transmission. But here’s the problem: the splines can strip out, especially under load or aggressive driving.

Once these splines are worn or stripped, the hub can no longer properly engage, resulting in:

Slipping in certain gears
Grinding noises
Delayed or failed gear engagement

What causes it?
Usually, it’s a mix of torque load, wear over time, and the natural back-and-forth movement of clutch packs under throttle and deceleration.

What to look for:
You’ll often see wear grooves forming in the hub where the clutch engages repeatedly. These are early signs of failure that shouldn’t be ignored.

3. D Clutch Drum Shell Damage

Another failure point is the D clutch drum shell, which can wear out or even break over time. This isn’t just a cosmetic issue—damage here can affect internal fluid flow, gear engagement, and overall transmission performance.

Once the shell is compromised, you’re looking at:

Harsh or erratic shifting
Trouble staying in gear
Full transmission failure if left unchecked

4. Valve Body Issues

These 8-speed transmissions are fully electronic, so there are no bands or one-way clutches, and everything is controlled by solenoids inside the valve body.

Unfortunately, the valve body is prone to wear and can develop:

Solenoid failures
Hydraulic pressure leaks
Delayed shift engagement
Gear ratio errors that trigger warning lights

Why this matters:
The valve body is like the brain of your transmission. If it’s not functioning properly, even perfectly healthy internal components can’t do their job.

Diagnosing Dodge Ram 8-Speed Transmission Problems

If you’re experiencing any of the following symptoms in your Ram 1500 or other Dodge vehicle with the 8-speed automatic, it’s time to bring it in:

Hard or delayed shifts
Slipping between gears
Gear engagement issues (especially 2nd, 4th, or 6th)
Transmission warning lights
Grinding or whining noises during acceleration

At National Transmission, we use advanced diagnostic tools, live data monitoring, and physical inspections (like pan drops and clutch pack checks) to isolate the issue quickly and accurately.

The National Transmission Solution

We don’t just replace broken parts! We install updated, heavy-duty components designed to eliminate repeat failures. Whether it’s a pressure plate, hub, drum, or valve body, we’ll walk you through the best repair options for your vehicle and budget.

Our services include:

✅ Full diagnostic scan and road test
✅ Transmission fluid and debris inspection
✅ Replacement with updated Sonnax or OEM parts
✅ Precision rebuilds and torque converter checks
✅ Expert installation and testing

Don’t Wait for Your Transmission to Fail

The Dodge Ram 8-speed transmission is a high-performance unit, but that also means it needs expert care when things start to go wrong. Ignoring the early signs can lead to full transmission failure and a much bigger repair bill down the road.

If your Ram 1500 is acting up, don’t wait – book your inspection with National Transmission today.

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🛠️ Trusted transmission specialists since 1978