E88 · 2008–2010
From April 2008 to February 2010 the 135i Convertible uses the same N54 twin-turbo six as the Coupé. Its maintenance adds two body-specific items: the rollover bar test and the hydraulic top.
Figures apply to the cited configuration and market; equipment and transmissions may vary by production date.
Specification source : [3] BMW Group
2,979 cc twin-turbo with High Precision Injection: 225 kW at 5,800 rpm, 400 Nm from 1,300 to 5,000 rpm. Six-speed manual or six-speed automatic. BMW quotes 0–100 km/h in 5.6 s; BMW Austria’s 03/2008 price list gives 9.4 l/100 km. Euro 4.
Oil change with filter: 6.5 l according to TIS data for the N54 B30, the same figure as BMW’s press table. Longlife-04 oils are approved for petrol engines only in the EU, Switzerland, Norway and Liechtenstein; outside that area, use the approval BMW specifies for the country.
The oil due date is calculated from the fuel used. BMW starts from 25,000 km for petrol engines and encodes 30,000 km for the ECE N54 from 09/2008. At every oil service: oil and filter, handbrake check, microfilter. Every third oil service: air filter and spark plugs. Front and rear pads, brake fluid and the vehicle check each have their own service.
At the vehicle check, the workshop triggers the rollover protection system via the diagnosis interface, with the top opened first. The top’s hydraulic system is filled for life: no fluid change is scheduled, and only the approved fluid is used if it leaks.
Chain-driven. The N54 TIS describes chain replacement, but no chain item appears among the maintenance operations: it is a repair, not scheduled maintenance.
In the United States, BMW of North America started a voluntary emissions recall in October 2010 covering model year 2008–2010 135i cars: the high-pressure fuel pump may fail, with long cranking, the engine warning light on and sometimes reduced power. The remedy was a new pump and/or a software update, depending on the car’s history. Following a US court-approved settlement, BMW then extended the emissions warranty of the turbocharger wastegate to 8 years or 82,000 miles for model year 2008–2010 E82 and E88 135i cars. BMW states that a slight wastegate rattle is normal, but a clank repeated up to six or seven times when decelerating from about 3,500 rpm should be diagnosed. Both measures cover US cars; the sources consulted show no equivalent action in Europe. In practice: unusually long cranking with the engine light on, or clanking from the turbos, warrants a prompt diagnosis. Also ask a BMW workshop to check open campaigns against your VIN.
Have the engine code read to confirm the N54. If the vehicle check is due, the rollover bar test is part of it; also report any slow movement or leak of the top. Brakes by axle: 338 mm vented discs at the front, 324 mm at the rear.
CBS: starting value 25,000 km
The CBS calculates the due date from the fuel used: 25,000 km is only a starting value. From 09/2008 BMW encodes 30,000 km for several ECE petrol engines, including the N54; the list does not name the N52K.
Source [2]CBS due date per axle
Two separate services. Pads replaced, brake air ducts cleaned, discs checked (surface, thickness) and replaced below minimum thickness; at the rear the handbrake is checked too.
Source [10]At every oil service
With air conditioning: microfilter replaced at every oil service, per BMW’s operation list for petrol models built from 03/2007.
Source [17]Every third oil service
Replaced at every third oil service, so they follow the oil interval calculated by the CBS.
Source [17]Every third oil service
Filter element replaced at every third oil service; BMW asks for shorter intervals in dusty regions.
Source [17]Due date shown by the CBS
A separate service: brake fluid replaced, then the CBS display reset. The documents consulted for the Coupé and Convertible do not state the interval.
Source [11]Due date shown by the CBS
Same scope as the Coupé plus one Convertible item: the workshop triggers the rollover protection system via the diagnosis interface, after opening the top first.
Source [12]No scheduled change
The system is filled with lifetime fluid. If it leaks, only the approved fluid may be used; the system bleeds itself through repeated operation of the top.
Source [13]Read the engine code. ADAC dates the N54 135i Convertible from April 2008 to February 2010; BMW announced the new single-turbo six for spring 2010.
At the vehicle check it triggers them via the diagnosis interface, after opening the top. This test is in BMW’s vehicle check list for the Convertible.
Source : [12]
Yes, TIS describes an emergency procedure: front doors open, rear windows fully lowered, top compartment lid unlocked from the luggage compartment, then the top lock released with the hexagon socket from the on-board tool kit. BMW requires two people and even force on both sides so the frame does not bend.
Source : [14]
6.5 l including the filter, according to TIS for the N54 B30.
Source : [7]
It was run by BMW of North America for US cars of model years 2008 to 2010. The sources consulted show no equivalent European campaign: have a BMW workshop check your VIN.
Source : [15]
BMW AG — TIS (archive) · EN · Europe · SI 11 03 04 (156) · revision 09/2005 · Accessed 08/10/2026
BMW AG — TIS (archive) · EN · ECE · SI 00 13 07 (391) · 10/2007 · launch 09/2008 · Accessed 08/10/2026
BMW Group · EN · Europe · Word attachments: Brief description · long version (soft top, rollover protection) · Technical Data 118i, 120i, 125i, 135i, 120d · Accessed 08/10/2026
BMW Group · DE · Germany · Presse-Information (PDF attachment), pp. 1–3 · Accessed 08/10/2026
BMW Austria · DE · Austria · “BMW 1er Reihe Coupé E82” and “BMW 1er Reihe Cabrio E88” · kW/PS, consumption, type keys · Accessed 08/10/2026
ADAC · DE · Germany · Technische Daten: Motorcode, Modellstart/-ende (Automatic: ID 211726) · Accessed 08/10/2026
BMW AG — TIS (archive) · EN · Europe · TD 11 40 · oil change volume with oil filter; E82 archive · Accessed 08/10/2026
BMW AG — TIS (archive) · EN · Europe · RA 11 31 051 · E82 archive · Accessed 08/10/2026
BMW AG — TIS (archive) · EN · Europe · RA 00 00 610 · E88 archive copy · Accessed 08/10/2026
BMW AG — TIS (archive) · EN · Europe · RA 00 00 612 (front) and RA 00 00 614 (rear, next document) · E82 archive · Accessed 08/10/2026
BMW AG — TIS (archive) · EN · Europe · RA 00 00 618 · E82 archive · Accessed 08/10/2026
BMW AG — TIS (archive) · EN · Europe · RA 00 00 625 · E88 archive: “Trigger rollover protection system (Convertible) via diagnosis interface” · Accessed 08/10/2026
BMW AG — TIS (archive) · EN · Europe · RA 54 34 · “No changing of the hydraulic fluid necessary” · Accessed 08/10/2026
BMW AG — TIS (archive) · EN · Europe · RA 54 34 · E88 archive · Accessed 08/10/2026
BMW of North America (NHTSA file) · EN · United States · Dealer message of 26 Oct 2010, pp. 1–2: model year 2008–2010 135i · Accessed 08/10/2026
BMW of North America (NHTSA file) · EN · United States · June 2013 revision (supersedes July 2012), pp. 1–3: E82, E88 MY 2008–2010 135i · Accessed 08/10/2026
BMW AG — TIS (archive) · EN · Europe · RA 00 00 610 · E82 archive copy · Accessed 08/10/2026