5L40E Pump, remanufactured and ready to install. Fits the 5L40E. Ships fast from the USA.
If your BMW with the 5L40E five-speed automatic (BMW calls it the A5S 360R) is slipping in every gear, taking a long time to pick up Drive or Reverse, or setting gear ratio codes after it warms up, the front pump is one of the first places to look. This is a remanufactured 5L40E pump and bell housing assembly for the BMW version of the transmission, the unit used behind the E46 3 Series, E39 5 Series and Z3.
On the 5L40E the pump body is machined into the front of the bell housing casting, which is why this part comes as one assembly instead of a separate pump you bolt into a case. The pump is driven by the torque converter hub and is a vane-and-slide design, so its output changes with engine speed and demand. It feeds every clutch, the torque converter and the cooler and lube circuits.
The main pressure regulator valve also lives in this pump body, not in the valve body. Sonnax notes that on the 5L40-E and 5L50-E this valve oscillates constantly and wears its own bore. Once that bore is worn, oil leaks past the valve and line pressure drops. A worn regulator bore and a worn slide or vanes both show up the same way from the driver's seat: the transmission cannot hold the clutches tight enough under load.
A pump fault affects all ranges at once. If only one gear slips, look at the clutch pack or the solenoid for that range first. Before you order a pump, check the fluid level and condition, read any stored codes, and if you can, put a gauge on the transmission and compare line pressure in Drive and Reverse at idle and under load. Our guide on checking transmission line pressure walks through the test, and the slipping diagnosis guide helps separate a pressure problem from a worn clutch. Low pressure across every range with good fluid points at the pump assembly or a stuck regulator. A slipping single gear with normal pressure does not.
This assembly is the BMW 5L40E version. The 5L40E was also built for GM cars such as the Cadillac CTS, STS and SRX, Pontiac Solstice and Saturn Sky, but those units bolt to GM engines, so this bell housing is not listed for them. To confirm you have the BMW unit, Transmission Digest says to look for a G or Z on the identification tag on the case. Match the tag, the bell housing shape and your car's year before you buy, or send us your year and VIN and we will check it. You can browse other 5L40E and 5L50E parts on our 5L50E and 5L40E collection page.
| Fits | 5L40E |
| Part type | Pump |
| Condition | Remanufactured |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
It is listed as the BMW pump and bell housing assembly. GM-car 5L40E units bolt to GM engines and use their own housing, so this part is not listed for them. Check your tag and send us your VIN if you are unsure.
On the 5L40E the pump body is cast into the front of the bell housing, so the pump is serviced as one assembly with the housing.
A pump or pressure regulator problem shows up in every gear and Reverse, usually worse when hot. A single slipping gear with normal line pressure points to that clutch or its solenoid instead.
A new front converter seal, the housing-to-case seal, a filter and pan gasket kit, and fresh fluid. If the pump wore out and left debris, flush the cooler and lines too.
Clear any stored codes and let the control module relearn its shift adaptations. Shift quality can feel off for the first drives until it does.
