4L70E Pressure Control Solenoid, new and ready to install. Fits the 4L70E. Ships fast from the USA.
If your 4L70E-equipped Silverado, Sierra, Tahoe, Yukon or Trailblazer SS has started banging into Drive, slurring the 1-2 and 2-3 shifts, or flaring when you pull a trailer up a grade, line pressure is the first thing to look at, and the pressure control solenoid is the part that sets it. This is a new replacement EPC solenoid that interchanges with GM 24248893, the late-style force motor used in the 4L60E family from 2003 on. It is a single solenoid with its O-rings, sold at a price that makes sense to replace while the pan is already off.
The 4L70E has no throttle cable. The computer reads engine load and throttle position, then sends a pulse-width-modulated current to this solenoid. Inside is a coil and a spool valve that bleeds control oil in proportion to that current, and the resulting signal goes to the pressure regulator and boost valve in the pump. The relationship is inverse: at idle the solenoid draws roughly 0.9 to 1.1 amps and line pressure sits low, and at wide-open throttle the command drops toward zero so line pressure rises to its maximum. Every clutch pack and the 2-4 band in the 4L70E is applied by that one pressure, so a solenoid that sticks, leaks internally or weakens shows up in every gear, not just one shift.
Watch the commanded and actual EPC current on a scan tool. A healthy command should swing from about an amp at idle down toward zero as you go to full throttle; if the current tracks but the shift feel does not change, the problem is hydraulic, not electrical. Then put a gauge on the line pressure port. Low pressure with a correct command points to a worn pressure regulator bore in the pump or worn actuator feed limit valve rather than the solenoid. Sonnax lists erratic line pressure, low line rise and 3-4 clutch failure as signs of regulator bore wear in 4L60-E, 4L65-E and 4L70-E pumps. Our 4L70E EPC solenoid symptoms guide walks through the amperage test step by step, and the 4L70E valve body testing guide covers the bores that mimic a bad solenoid.
This is the late-style EPC. GM ran two designs: an early style through 2002 and a late style from 2003 on, with different pin and connector layouts, so the two do not plug into each other's harness. Every 4L70E falls in the late-style period, including the 2006-2013 trucks and SUVs listed above, and the same solenoid interchanges into 2003-up 4L60E and 4L65E units. The listing does not carry a single model year, so compare the connector and body shape in the photo with the solenoid in your pan, or check the number stamped on your old part against 24248893. If you are unsure, send us your year and VIN. The rest of our parts for this transmission are on the 4L70E collection page, and the 4L60E, 4L65E and 4L70E interchange guide explains what crosses over between the three.
If the truck also has a converter shudder or lockup complaint, the 4L70E TCC solenoid sits a few inches away and comes out the same way. If the pan shows burnt frictions, step up to a 4L70E overhaul kit rather than hoping a new solenoid will bring a slipping 3-4 pack back.
| Fits | 4L70E |
| Part type | Pressure Control Solenoid |
| Condition | New |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It is the late-style EPC that interchanges with GM 24248893, which is the design every 4L70E uses. Compare the connector on your old solenoid with the photo, or send us your year and VIN to confirm.
Only in 2003-up units. 1993-2002 transmissions use the early-style EPC with a different connector and pin layout, so this solenoid will not plug into that harness.
P0748 is the circuit code. A solenoid that is mechanically sticking may set no code at all and only show as harsh or soft shifts, which is why an amperage and line pressure check is worth doing first.
Line pressure is also controlled by the pressure regulator and boost valve in the pump and the actuator feed limit valve in the valve body. Worn bores in either keep pressure wrong no matter how good the solenoid is.
Use Dexron VI and check the level hot. Clear codes after the repair; the computer adapts shift timing over the next several drives, so give it time before judging shift feel.
