8L90 Tcc Solenoid 2017, new and ready to install. Fits the 8L90. Ships fast from the USA.
This is a new torque converter clutch (TCC) lock-up solenoid for the GM 8L90 eight-speed, listed under GM number 24272280 for 2017 and later units. The 8L90 sits behind the V8 engines in Silverado and Sierra pickups, Tahoe, Suburban, Yukon and Escalade SUVs, and the Camaro and Corvette. Owners usually find this part while chasing a converter that will not lock, a TCC code, or the well-known 8L90 shudder at highway speed. Before you order, read the diagnosis section below: on this transmission the shudder is usually a fluid problem, and the solenoid is the fix only when the lock-up circuit itself has failed.
The 8L90 valve body carries nine solenoids. Seven are variable force pressure control solenoids and two are on/off units. GEARS Magazine identifies the TCC pressure control solenoid as S7, a high-pressure, normally low design: with no current it sends no signal, and as the TCM raises current it builds signal pressure that strokes the TCC control valve and applies the converter clutch. Because it is a variable force unit rather than a simple on/off switch, the TCM can hold the converter in controlled slip at light load and full lock at cruise. Every pressure control solenoid in this unit measures 4.5 to 5.5 ohms, and each position has its own part number and flow rate, so solenoids must go back in their original locations.
Start with the fluid. GM Service Bulletin 18-NA-355 lists a 25 to 80 mph shudder on 8L45 and 8L90 vehicles and calls for a complete flush with Mobil 1 Synthetic LV ATF HP. GEARS Magazine reports the original fluid absorbed moisture and changed its friction behavior, and that the flush cures true TCC shudder in almost every case, though it can take up to 400 miles to settle. If the truck shudders but sets no codes, do that first. If you have a TCC code, measure solenoid resistance at the case connector and compare commanded versus actual slip on a scan tool. Our 8L90 solenoid symptoms guide covers the electrical tests, and 8L90 common problems and fixes explains the shudder bulletin in detail.
The listing describes this solenoid as the 8L90 TCC lock-up solenoid for 2017-up GM, OEM 24272280. The 8L90 and 8L45 share the solenoid family, but GM revised valve body parts over the years, including a 2019 change to the S4 control valve and solenoid. Pull your old solenoid and compare the part number on it to 24272280, or send us your year and VIN before ordering. If you prefer a remanufactured unit carrying the same reference number, see our remanufactured 8L90 TCC solenoid, and browse the full 8L90 parts collection.
Since the pan is down, replace the 8L90 filter kit with gasket. If the fluid ran hot, check the 8L90 thermal bypass valve as well, since a stuck valve limits cooler flow and cooks the new fluid.
| Fits | 8L90 2017 |
| Part type | Tcc Solenoid |
| Condition | New |
| Brand | OEM |
| Reference | 24272280 |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
Usually not on its own. GM traced most 8L90 shudder to moisture-contaminated fluid and fixes it with a full flush to Mobil 1 Synthetic LV ATF HP. Replace the solenoid when you have a TCC code or a failed resistance test, or when shudder continues after a proper flush.
Yes. The 8L90 TCM stores characterization data for each solenoid. After replacing a solenoid, the TCM must be updated with the new part unique number through GM service programming.
The 8L45 and 8L90 share this solenoid family, and the same GM number is listed for both. Compare the number on your old solenoid to 24272280 before ordering.
GEARS Magazine lists 4.5 to 5.5 ohms for all 8L90 pressure control solenoids, including the TCC solenoid. A reading well outside that range, or an open circuit, confirms an electrical fault.
Use Mobil 1 Synthetic LV ATF HP or another DEXRON HP licensed fluid. Avoid older black-bottle or gray-label fluid, which GEARS Magazine flags as earlier formulations.
