Smart Fortwo Engine Oil Change — 450, 451, 453
Service interval: Every 10,000 mi or 12 months (NA petrol and 453) · Every 6,000 mi or 12 months (Brabus and CDI turbo)
Tools you'll need
- Jack and a pair of jack stands (or ramps)
- Wheel chocks
- Drain pan (4L+)
- Oil filter wrench (cap-style for the 451 cartridge filter)
- Socket set with the right hex/Torx for your drain plug
- Torque wrench
- New crush washer for the drain plug
- Funnel
- Nitrile gloves and shop rags
Fluids & specs
| Fluid | Spec | Capacity |
|---|---|---|
| Engine oil — 450 (gasoline 0.6 / 0.7L) | 5W-40 semi-synthetic; mineral 5W-40 was original | ~3.0L with filter |
| Engine oil — 451 NA / Brabus (M132 1.0L petrol) | 5W-30 ACEA C3, MB 229.51 approval | ~3.4L with filter |
| Engine oil — 451 CDI (diesel) | 5W-30 low-SAPS, MB 229.51 or equivalent | ~3.7L with filter |
| Engine oil — 453 (H4Bt 0.9L turbo or B4D 1.0L NA) | 5W-30 Renault RN0700 (NA) / RN0710 (turbo) | ~3.5L with filter |
What this is and why it matters
Engine oil is the cheapest, easiest job that has the biggest payoff on a Smart. The M132 petrol in the 451 and the H4Bt turbo in the 453 are both small, hot-running engines that punish stretched intervals and the wrong oil spec. Doing it yourself once a year takes under an hour and saves a shop visit.
The procedure is the same shape across all variants: warm the engine, drain the old oil, swap the filter, refill, check the level, run it, recheck. The differences are oil spec, capacity, drain plug location, and filter type. Get those right and the rest is just turning bolts.
What you'll need
The tools and fluid specs are listed in the tables above. A few notes:
- A cap-style oil filter wrench sized for your filter housing is worth the $15. Strap wrenches slip on hot housings.
- Buy a fresh crush washer every change. Reusing them is how owners end up with a slow drip on the floor.
- For the 453, a small funnel with a long neck makes the fill a lot easier than freehanding from the jug.
Step by step
This is the generic procedure. See the model-specific notes in Common gotchas for variant differences.
- Warm the engine. Five minutes of idle, or a short drive. Warm oil drains faster and pulls more grit out with it. Don't run it long enough that the drain plug is dangerous to touch.
- Lift and secure the car. Jack stands on the rated lift points, or solid ramps. Always chock the wheels. Never crawl under a Smart sitting on a jack alone.
- Find the drain plug and the filter. On the 450 and 451 the plug is in the steel sump under the engine, and the M132 filter is a cartridge in a plastic housing on top of the engine — accessed through the rear hatch with the plastic engine cover off. On the 453 the plug and the spin-on filter are both accessed from underneath.
- Drain the old oil. Position the pan, crack the plug loose with a socket, then back it out by hand the last few turns. Let it drain for at least ten minutes — most of the volume comes out in the first minute, but the last bit is where the suspended dirt lives.
- Swap the filter. On the 451 cartridge, unscrew the housing cap, pull the old element, replace the O-rings that come with the new filter kit, drop the new element in, and torque the cap to spec (workshop manual; typically around 25 Nm, but verify for your year). On the 453, spin off the old filter, smear a film of fresh oil on the new gasket, and hand-tighten plus about three-quarters of a turn.
- Reinstall the drain plug with a new crush washer. Snug, then torque to the spec for your engine. Don't gorilla it — these threads are aluminium on most variants and they will strip.
- Refill with the correct oil and capacity. Pour in roughly 0.3L less than the listed capacity, then check the dipstick before topping off. Overfilling a small engine is worse than running it half a quart light.
- Run the engine and recheck. Start it, watch the oil pressure light go out within a couple of seconds, then idle for a minute. Shut it off, wait five minutes for the oil to settle, and check the dipstick. Top off as needed. Look under the car for any drips at the plug or filter.
- Reset the service indicator if your variant has one. The 453 in particular wants the service reminder reset through the menu — not strictly required, but it stops the dash nag.
Common gotchas
- Oil spec is not negotiable on the 451 M132. It's a Mercedes engine and it wants MB 229.51 approval on the bottle. Generic 5W-30 without the approval will work short-term but it's not what the spec sheet calls for. Same goes for the CDI on the diesel side.
- The 453 takes Renault spec, not Mercedes spec. The 453 was built on the Renault Twingo platform and the engine wants RN0700 (1.0L NA) or RN0710 (0.9L turbo). Don't buy MB 229.51 by reflex if you've owned a 451.
- Drain plug location varies. The 450 and 451 petrol have the plug at the rear of the sump under the engine. The 451 CDI plug sits in a different spot on the diesel sump. The 453 plug is on the underside, more forward. Crawl under and look before you assume.
- Brabus and turbo intervals are shorter. Turbocharged variants run hotter and shear oil faster. 6,000 miles is a sane interval for a Brabus 451 daily driver. Track use, even shorter.
- The 451 cartridge filter has multiple O-rings. When the kit comes with three rings, all three go on. Owners who skip the small inner ring get a leak that looks like a main seal failure.
- Don't over-torque the drain plug. Smart sumps are aluminium. A heli-coil repair is a $200 job that started with someone leaning on a 3/8" ratchet too hard.
When to skip DIY
If you don't have a way to lift the car safely — proper jack stands, a lift, or solid ramps — this is a job to outsource. Working under any car on a single jack is how people get killed. The same goes if your driveway is on a slope, if you can't dispose of used oil locally, or if you're not confident reading a torque wrench. A shop oil change on a Smart runs $80-150 depending on whether they use the right oil, which is the other reason a lot of owners do it themselves: a quick-lube place that grabs whatever bulk 5W-30 is on the rack is not doing your M132 any favours.
Parts & typical prices
| Part | Typical price | Search |
|---|---|---|
| Oil filter cartridge (451 M132) | $8-18 | Search Google |
| Oil filter (453 H4Bt / B4D) | $10-20 | Search Google |
| Drain plug crush washer | $1-3 | Search Google |
| 5L jug of MB 229.51 5W-30 | $35-60 | Search Google |
| 5L jug of RN0700 / RN0710 5W-30 | $35-55 | Search Google |
Prices are rough community-reported ranges, not quotes. Aftermarket vs. genuine Mercedes parts swing the spread.
Manual references
- Browse Smart workshop manuals on smartcarmanuals.com — model-specific reference manuals on the home page; pick your chassis code section for torque specs and detailed procedures.
