8L90 Pump, new and ready to install. Fits the 8L90. Ships fast from the USA.
This is a brand-new, genuine GM stator support assembly with its shaft for the 8L90 eight-speed, sold in GM packaging under part number 24288793. GM lists it with the pump hardware, which is why it is catalogued here as an 8L90 pump part, but it is specifically the front stator support and shaft, not the off-axis pump rotor set or the drive chain. It suits 2015 and later 8L90 units in V8 Silverado and Sierra pickups, Tahoe, Yukon and Escalade SUVs, Camaro SS and ZL1, Corvette and CTS-V. Buyers usually land here with a scored stator shaft, a cracked or damaged support after a converter failure, or a unit that drops out of gear at a stop and will not hold a C5 clutch adapt.
The stator support bolts to the front of the case and its splined shaft holds the torque converter stator still, so the stator one-way clutch can redirect fluid and multiply torque at launch. The input shaft runs through the middle of it, and the passages machined into the support and its cover carry converter feed, converter release and clutch apply oil from the valve body to the front of the transmission. On the 8L90 the pump itself sits off-axis and is driven by a chain, so the support is not where pressure is made, but a leak in its passages or seal-ring bores wastes the pressure the pump does make.
GEARS Magazine documents two details that matter when replacing this part. Early 8L units could trap air in the stator cover passages, causing delayed engagement or dropping out of gear at a stop; GM updated the 8L90 support and cover with an extra check ball and revised passages so the C5 circuit purges air and stays charged. GM also built two stator and input shaft designs: the standard design with a stator bushing for gas engines without Dynamic Fuel Management, and a shorter, bushing-free stator shaft paired with a longer input shaft for CPA torque converters used on DFM and diesel applications. The two cannot be converted into each other.
Rule out the cheap causes first: correct fluid level, a completed fast learn and the pressure regulator and pump prime issues covered in our 8L90 pump failure guide. If engagement complaints persist, inspect the stator support with the unit apart. Look for scoring in the seal-ring bores, wear on the stator splines and the converter-side bushing, and cracks around the bolt bosses. Our 8L90 common problems guide sorts converter shudder from true hydraulic leaks so you do not replace the wrong part.
This listing is a new GM 24288793 stator assembly with shaft for 2015 and later 8L90 transmissions. It is not an 8L45 part. Before ordering, compare it with your old support: match the stator shaft length and whether your shaft has a converter-side bushing, because CPA and non-CPA units take different stators and input shafts. Aftermarket catalogs also cross this assembly to 334520B, D334520B and 154520B. If you are unsure, send us your year and VIN and we will check it. All 8L90 parts are on the 8L90 collection page.
| Fits | 8L90 |
| Part type | Pump |
| Condition | New |
| Brand | GM |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. It is the new GM 24288793 stator support assembly with shaft. The 8L90 pump rotor set is off-axis and chain driven, and the chain and sprockets are separate parts.
No. GM uses a different stator support for the 8L45. This assembly is for the 8L90 only.
Look at your old stator shaft. The standard design has a bushing on the converter side and the input shaft has a land where it rides. CPA units used with Dynamic Fuel Management and diesel engines have a shorter stator shaft with no bushing. Match what you have, or send us your VIN.
DEXRON HP. GM states the 8L90 uses DEXRON HP only, and a fluid change is about 7.4 quarts per GM's capacity chart.
Yes. Air trapped in the stator cover passages on early 8L units was a known cause of delayed engagement and dropping out of gear, and GM revised the support and cover to purge it.
