Nine-piece 2003-2006 GM 4L60E solenoid kit: shift A and B, 3-2, TCC, TCC PWM and EPC solenoids, harness with pressure switch, filter and pan gasket.
This is the most complete electrical kit we carry for the 2003-2006 GM 4L60E. Beyond the solenoids, it includes the internal harness with the pressure switch manifold already attached, which matters when your scan tool shows range or pressure switch codes along with shift, EPC or lockup faults. Drivers usually find it while chasing a harsh or missing upshift, a truck stuck in one gear, a converter that will not lock, or a mix of P0753, P0758, P0748, P0741 and P0742 codes on a high-mileage Silverado, Sierra, Tahoe, Suburban or Yukon.
Six solenoids run this transmission. Shift solenoids A and B are simple on-off valves that together select all four gears. The EPC solenoid is a variable-force valve that sets line pressure; ATRA lists its resistance far lower than the shift solenoids, around 3.5-8.0 ohms, because it is driven differently. The TCC solenoid enables lockup and the TCC PWM solenoid feathers the converter clutch on so it applies smoothly. The 3-2 solenoid controls downshift timing. All of them are fed by the AFL valve, which Sonnax describes as regulating line pressure to about 115 psi before it reaches the solenoids. The pressure switch manifold bolted to the valve body is not a solenoid at all. It is a set of hydraulic switches that tell the computer which range the manual valve is in, and a leaking or failed manifold confuses the computer about what gear it should be commanding.
Check codes, then do a resistance test at the case connector with the harness unplugged. Each circuit should fall within its listed range and stay steady while you flex the connector. A reading that only fails when hot, or several circuits failing together, points to the harness. GM has gone further than most on this: service bulletin PIP5009G tells technicians to replace the internal harness and TCC enable solenoid any time transmission repairs are done on later 4L60E family trucks. Our 4L60E shift solenoid testing guide gives the pin map, and our P0748 pressure control solenoid guide explains the EPC side. If a P0741 slip code remains after electrical checks pass, valve body bore wear is a known cause and should be checked before you buy more parts.
This kit is listed for the GM 4L60E from 2003-2006. Manufacturer part number SNTS4L60E-N01HS, with cross-references including 10478112, 10478120, 10478131, 24230298, 24220158, 24219581 and 24215111. The earlier 1993-2002 harness and pressure switch manifold are different, and GM changed parts within these years too, so match the new manifold, harness connectors and solenoid styles against what comes off your valve body. If you are unsure, send us your year and VIN. The full lineup is on our 4L60E transmission parts page.
Drop the pan, remove the filter, then unplug and unbolt the old harness and pressure switch manifold together. Remove each solenoid clip, fit new solenoids with their O-rings lubed in ATF, and lay the new harness in the same path as the old one so it cannot chafe on the case or valve body. The manifold seals directly against the valve body, so run its bolts down evenly in steps and do not overtighten them. Install the new filter and the cork pan gasket, refill with Dexron VI and check level hot. Clear codes and road test through all four gears and lockup. If the valve body has to come off, a GM 24241783 spacer plate with gaskets is worth having on hand, and a spare TCC PWM solenoid covers lockup feel issues later on.
| Transmission | GM 4L60E (2003-2006) |
| Includes | Shift solenoids A and B, 3-2 solenoid, TCC solenoid, TCC PWM solenoid, EPC solenoid, internal harness with pressure switch manifold, filter, pan gasket |
| Cross-reference | 10478112, 10478120, 10478131, 24230298, 24220158, 24219581, 24215111 |
| Manufacturer part number | SNTS4L60E-N01HS |
| Kit weight | 3 lb |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
This kit adds the internal harness with the pressure switch manifold attached, plus a filter and pan gasket. If you have pressure switch or range codes, or the old manifold is leaking, this is the kit to use.
It is listed for 2003-2006 4L60E units. Compare the manifold and connectors with your old parts, or send us the VIN to confirm before installing.
The manifold is already on the harness in this kit, so you replace it as part of the job. On a high-mileage unit it is cheap insurance, since the switches see the same heat and fluid as the solenoids.
ATRA lists the 4L60E pressure control solenoid at about 3.5-8.0 ohms across its two pins, much lower than the shift solenoids. Check the exact value for your year in the service information.
Dexron VI ATF. Refill, then check the level hot with the engine running in Park.
