4L60-E Series Input Shaft, Stator & Pump Cover Compatibility: Three Easy Checks

If the stator is misaligned or if the incorrect stator is used, it may cause no movement, converter charge concerns, input shaft failure and even converter damage in GM 4L60-E, 4L65-E and 4L70-E transmissions. Verifying the correct stator for your application can be broken down into three easy checks that look at the shaft, pump cover and stator itself.

1. Identify Shaft Type

It is extremely important to take note of sealing ring location because there are a few variations of shafts out there (Figure 1). You may find a pump cover that does not have the ISS hole drilled, but has a reluctor-style stator with no reluctor on the input shaft (see “Anomaly” in Figure 1). This situation will require the use of an ISS stator.

Figure 1 – 300mm Shaft Sealing Ring Locations

2. Identify Early vs. Late Pump Style

Using a ruler or straightedge, draw a line through the center of the pump bolt holes. Make note of whether the converter feed hole is positioned slightly off to the right or left of the line (Figure 2).

Figure 2 – Pump Cover: Converter Feed Hole in Relation to Bolt Holes

3. Identify Early vs. Late Stator Style

To determine which stator will work in the pump, look at the converter feed and lube holes in the stator. Make note of whether they are directly in line with one another or if the converter feed hole is positioned to the right of the lube hole (Figure 3).

Figure 3 – Stator: Converter Feed Hole in Relation to Lube Hole

As you can see with these three quick checks, you can easily determine which stator best fits your application. In earlier pumps, the converter feed hole will be just to the right of the line while — in the stator — the converter feed and lube holes will be directly in line. In later-model or GM’s most recent pumps, the converter feed hole will be just to the left of your line while — in the stator — the converter feed hole will be to the right of the lube hole.

Caleb Perham is a Sonnax product support representative. He is a member of the Sonnax TASC Force (Technical Automotive Specialties Committee), a group of recognized industry technical specialists, transmission rebuilders and Sonnax Transmission Company technicians.