Specs & Tips
Suggested specifications for a stock BMW 2002 (M10) — the period factory figures where BMW published them, and the products owners commonly use where they didn’t. Treat these as well-grounded suggestions, not gospel: your car, its year and any conversions it carries always win.
Engine oil & filter Period specification · owner practice
- Period oil spec: brand-name HD 20W-50 (SAE 20W-50 HD) — the figure in BMW’s handbook material for these cars.
- Today most owners still run 20W-50. The M10 was designed when motor oil carried more zinc (ZDDP) — modern oils carry less — so a high-zinc “classics” 20W-50 is the common choice; Valvoline VR1 20W-50 is the one Pelican Parts’ 2002 specialist names. More zinc is not always better, so use a formulated classics oil rather than heavy additive doses.
- Spin-on filter spec: Mann W 712/6 or Mahle OC 25 — BMW OE 11 42 1 258 039. Mahle also makes the OC 84, a higher-burst-strength version of the same filter (BMW 11 42 1 278 059) for colder climates; both are interchangeable on the M10.
- Brand guide — the safe defaults: Mann and Mahle are the OE-tier German makers, and what the marque vendors stock. Wix 51288 is the American-market equivalent (Wix is a Mann+Hummel brand, and NAPA Gold filters are Wix-made) and the one most often named by US owners.
- Fram, honestly: the “orange can of death” reputation targets the budget Extra Guard line — PH46A is the 2002 fitment — whose teardowns show fiber end caps and less media, though Fram’s engineers call the fiber caps a deliberate flex-with-the-pleats design. Their premium Ultra Synthetic line is a different, well-tested filter (full synthetic media on a wire screen, steel end caps) — but no Ultra part number is cataloged for the M10, so on a 2002 the Fram on the shelf is the orange can. Its 265-psi burst rating still clears the M10’s cold-start pressure comfortably; it’s a filter, not a time bomb.
- Two more names from the cross-reference charts: Hengst H90W04 (the other big German OE filter maker) and Bosch 72107 / 0 451 103 050 — the Bosch numbers appear in aftermarket crosses but couldn’t be verified in Bosch’s own catalog.
- Whatever brand you choose, mind the canister: the M10 sees 90–125 psi on a cold start, which is why BMW specified the 30-bar burst-pressure canister (...059 / OC 84). Don’t fit a light-duty filter here.
Spark plugs Period specification
- Plug: Bosch W7DC — the factory tuning-table specification; the current Bosch equivalent is WR7DC.
- Gap: 0.6–0.7 mm (0.024–0.028 in).
- At Major Service the factory renewed the plugs outright rather than cleaning and re-gapping them.
- W8DC (WR8DC) is one heat range hotter and widely documented in community use — W7DC/WR7DC is the spec.
- NGK alternative: the BPR6ES (NGK stock #7131) is the plug 2002 owners and parts guides pair with the WR7DC — 14 mm thread, 19 mm reach, resistor, copper. Reading the code: B = 14 mm thread, P = projected tip, R = resistor, 6 = heat range, E = 19 mm reach, S = standard copper.
- Resistor or not: W7DC is non-resistor (period), WR7DC and BPR6ES are resistor (modern). Either works on a stock points car — the resistor just suppresses radio interference; it matters more once you convert to electronic ignition.
- Denso: the stock-type copper equivalent of the NGK BPR6ES is the Denso W20EPR-U (cross-chart documented). Parts stores also list iridium/platinum Denso plugs (Iridium Power 5305 and the like) as upgrades. They’ll work, but stick with copper: it’s what the stock ignition was designed around, and at Major-Service change intervals you don’t need long-life alloys.
Points, cap/rotor & timing (stock ignition) Period specification
- Contact-breaker (points) gap: 0.4 mm (0.016 in).
- Dwell angle: 59–65° (factory tuning tables).
- Ignition timing marks and test speeds varied by year and distributor — set the timing with a strobe lamp to the figures in your car’s handbook.
- Cars converted to electronic ignition have no points to set — you can remove this item from your schedule.
Valve clearances Period specification
- Clearance, intake and exhaust: 0.15–0.20 mm (0.006–0.008 in) — the owner’s handbook figure, checked with the engine cold.
- A performance cam may call for different clearances — if your engine has one, the cam card wins.
Air filter Manufacturer catalog
- Stock element for the later/larger round air cleaner: Mann C 3260 (Mahle/Knecht LX 210), BMW OE 13 71 1 265 624 — fits above chassis 2583405 (manual) / 2532752 (automatic).
- Earlier cars took a smaller element, so check the element in hand before ordering.
- If your car wears a different airbox or carburettors, match the element to what is actually fitted.
Gearbox, diff & steering-box oil levels Period specification
- Period spec — gearbox: SAE 80 gear oil, explicitly not hypoid gear oil (the handbook allows HD engine oil as a substitute); the steering box uses the same oil.
- Period spec — final drive (differential): SAE 90 hypoid gear oil.
- Major Service checked levels rather than changing the oil — the change interval in your schedule is a time-based owner-practice item.
Gearbox & differential oil Period specification · owner practice
- Gearbox: the period spec is SAE 80 gear oil (not hypoid). Most owners and specialists today use a GL-4 gear oil — Red Line MTL is the name that comes up most — because GL-4 is the safe class around the Getrag’s brass synchro rings; GL-5’s additives can attack them.
- Differential: the period spec is SAE 90 hypoid. A GL-5 75W-90 or 80W-90 is the common modern fill.
- Don’t swap them: GL-4 in the gearbox, GL-5 in the diff.
Brake fluid Owner practice
- The period manual specified DOT 3. Today DOT 4 is the standard fill — higher boiling points, fully compatible with a DOT 3 system, and what specialists use.
- Brake fluid is hygroscopic — it absorbs moisture over time, which is why it is renewed on a time interval even on a car that barely turns a wheel.
Fuel filter Period specification · owner practice
- Stock filtration on a carbureted car: a screen at the tank pickup plus a small filter element inside the mechanical fuel pump, BMW part 13 31 068 0125.
- The ubiquitous clear in-line filter in the engine bay is a later aftermarket addition, not original equipment. If one is fitted, replace it pointing the arrow with the flow direction.
- Only the fuel-injected 2002tii had a separate metal canister filter — don’t confuse the two.
Coolant Period guidance · owner practice
- Period guidance was plain soft water with anti-corrosion / antifreeze protection — no modern coolant specification existed for these cars.
- Modern practice: a 50/50 mix of aluminium-compatible ethylene-glycol antifreeze and water; distilled water is the kindest mixer.
- Pick one quality coolant and stay with it rather than mixing types.
Tires & pressures Period specification
- Stock tire size: 165 SR 13 (165 HR 13 on the 2002tii). 185/70 R 13 is the diameter-matched substitute owners commonly fit today; the often-suggested 175/70 R 13 runs slightly smaller in diameter and was not a factory size.
- Cold pressures, 165 SR 13 (1976 US owner’s manual): 26 psi front / 26 psi rear with up to 3 occupants; 26 front / 29 rear fully loaded.
- Cold pressures, 165 HR 13 (tii): 27 psi front / 27 psi rear; 29 front / 32 rear fully loaded.
- Factory figures varied by year and market — your car’s handbook or placard wins over any general table, this one included.
Sources: BMW period owner’s handbook and factory tuning tables (via BMW 2002 FAQ), the Mann, Mahle and Wix filter catalogs, NGK application data, aftermarket cross-reference charts, marque specialist guidance (Pelican Parts, Ireland Engineering), and owner/teardown discussion (BMW 2002 FAQ, BobIsTheOilGuy). Verified October 2026.
