5L40E Clutch Drum, used and ready to install. Fits the 5L40E. Ships fast from the USA.
If your 5L40E slips on the 2-3 shift, flares into fifth, or sets a fifth-gear ratio code that keeps coming back, the overdrive and intermediate clutch housing belongs on your inspection list. This is a used OEM 5L40E/5L50E overdrive and intermediate clutch drum, interchange number 144550C, built for the 2003-up design with a 2-clutch overdrive pack and a 3-clutch intermediate pack that use internal-tooth frictions. It is the housing found in BMW 3 Series, 5 Series, X5 and Z3 models and in GM cars such as the Cadillac CTS, STS and SRX, Pontiac Solstice and G8, and Saturn Sky.
GM's 5L40E stacks two clutches in one housing here. The intermediate clutch comes on for the 2-3 shift and the overdrive clutch comes on for the 4-5 shift; the Sonnax 5L40E/5L50E test guide ties the intermediate clutch accumulator to 2-3 slip or harshness and the overdrive clutch accumulator to 4-5 slip or harshness. The drum carries both pistons and is fed from the case through a seal sleeve between the valve body and the housing, so a worn sleeve, a cracked piston bore or a damaged ring groove robs both clutches of apply pressure. The housing is held in place by a selective retaining ring that GM sizes from a measured gap, which is why this part has to be set up, not just dropped in.
Several valve body faults mimic a bad drum. Transmission Digest lists the overdrive accumulator, the case seal sleeve feeding the overdrive/intermediate housing and the number 12 checkball as known causes of a fifth-gear ratio code, and Sonnax notes that a worn AFL valve can cause overdrive clutch distress and gear ratio codes. Start with fluid condition and a line pressure check, then use our flare vs slip guide to judge which shift is affected. With the unit apart, air-check both pistons separately. A housing with a scored bore, cracked piston cavity or cut ring land is the reason to buy this part.
This drum is listed for 2003-up 5L40E and 5L50E units. The earlier design is different: if your transmission is a 1999-2002 BMW unit, look at our 5L40E 2000-up drum instead and compare. Because this is a used part from a running unit, count the clutches your old drum held (2 overdrive, 3 intermediate on this one), compare the hub and the photo, and check the ID tag on the left rear of the case. If you are unsure, send us your year, model and VIN before ordering. More parts for this family are on the 5L50E and 5L40E parts page.
| Fits | 5L40E |
| Part type | Clutch Drum |
| Condition | Used |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
It is the overdrive and intermediate clutch drum (interchange 144550C), with a 2-clutch overdrive pack and a 3-clutch intermediate pack. The forward and coast drum with the long shaft is a different part.
This drum is listed for 2003-up units. Earlier units may use a different design, so compare your old drum to the photo and count the clutches, or send us your VIN and we will check it.
The intermediate clutch applies on the 2-3 shift and the overdrive clutch on the 4-5 shift, so a leaking drum shows up as 2-3 or 4-5 slip, no fifth gear, or a fifth-gear ratio code such as P0735.
Yes. Plan on new piston seals, sealing rings and any burnt frictions, then set piston travel to GM spec with the plates you install.
Use the fluid your vehicle maker specifies. GM lists Dexron III for its 5L50E applications; BMW cars use the fluid BMW specifies for that transmission.
