4L70E Pump, new other (see details) and ready to install. Fits the 4L70E. Ships fast from the USA.
If your 4L70E, 4L65E or 4L60E pump came apart with a cracked rotor, or you are building a towing or high-horsepower unit and do not want to trust another powdered-metal rotor, this is the part you are shopping for. It is a single 10-vane pump rotor machined from heat-treated 416 stainless billet, new old stock that has never been installed. It is not a complete pump assembly: it replaces the rotor that sits inside your existing pump body, between the slide and the vane rings.
The 4L70E uses a variable-displacement vane pump driven by the converter hub. The rotor is splined to the hub, and the vanes riding in its slots sweep fluid around the inside of the slide. The pressure regulator moves the slide to change how much oil the pump moves, which is how line pressure stays where the transmission control module wants it. Every clutch apply, the 2-4 band and converter lockup all depend on this one rotating group. When the rotor cracks, pressure collapses or turns erratic and debris goes straight into the pump pockets.
GM built these pumps with 10-vane rotors originally, then moved to a 13-vane rotor in 1997 to quiet pump whine and pressure regulator buzz. ATSG's Wayne Colonna notes that the extra slots leave less material between vanes, which makes the factory powder-metal 13-vane rotor more prone to breaking. A solid billet 10-vane rotor keeps more metal between the pockets, which is why rebuilders choose it for towing and performance builds.
The 4L70E's known weak points, burned 3-4 clutches and TCC apply complaints with P0741, often trace back to pressure problems, so a tired pump can be part of the story.
A rotor fault is confirmed on the bench, not in the driveway. Start with fluid level, a line pressure gauge and a look in the pan. Then pull the pump, unbolt the cover and inspect the rotor, vanes, slide, pivot pin and pocket. Our 4L70E pump failure guide walks through the test order, and the delayed engagement guide covers the cases where the pump is innocent. Before you install a new rotor, find out why the old one broke. Colonna lists high line pressure from a stuck regulator valve or a failed pressure control solenoid, air drawn in past the filter, a restricted filter, shallow converter engagement and misalignment as the usual causes.
This rotor is listed for 4L60E, 4L65E and 4L70E front pumps, plus 200-4R, 700R4 and 4L60 pumps set up with matching 10-vane parts. That last condition matters. If your pump currently runs 13 vanes, as most 1997 and later units do, you need 10 vanes and a compatible slide and rings to go with this rotor. Measure your pump pocket and compare it to the rotor before assembly, and send us your year and VIN if you are unsure what pump you have. Browse the full 4L70E parts collection for the rest of the build. If you would rather keep the factory 13-vane layout, the 13-vane replacement rotor and the 13-vane rotor kit are the stock-style choices.
Because a cracked rotor is often a pressure problem in disguise, pair it with the parts that control pressure: a fresh 4L70E pressure control solenoid and, for a full rebuild, the 2004-2013 overhaul kit.
| Fits | 4L70E |
| Part type | Pump |
| Condition | New Other (See Details) |
| 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.
No. It is the pump rotor only, a billet steel 10-vane rotor. You reuse your pump body, cover and slide or supply matching 10-vane components.
Only if you convert the rotating group. You need 10 vanes and a slide and vane rings that match this rotor. If you want to keep the factory 13-vane setup, use a 13-vane rotor instead.
Common causes are high line pressure from a stuck pressure regulator or failed pressure control solenoid, air ingestion, a restricted filter, shallow converter engagement and misalignment. Fix the cause or the new rotor is at risk too.
At minimum the front seal, pump bushing, pump seals and filter. Inspect the slide, pivot pin and pocket. For a high-mileage unit an overhaul kit and a new pressure control solenoid are worth adding.
GM specifies Dexron VI automatic transmission fluid for 4L70E applications. Prime the pump with fluid before the first start.
