The R107 used several transmissions over its 18-year run. Knowing which one you have matters for fluid, parts and diagnosis.
Transmission by model and year
| Model | Typical transmission |
|---|---|
| 350SL / 450SL (US, 1972–1980) | 3-speed automatic, 722.0 family |
| 280SL (Euro) | 4-speed automatic (722.1 family) or manual |
| 380SL (US, 1981–1985) | 4-speed automatic, 722.3 family |
| 560SL (US, 1986–1989) | 4-speed automatic, 722.3 family |
| 500SL, 420SL, 300SL (Euro) | 4-speed automatic, manual available on some |
Gearbox fitments changed by market and year; confirm with your data card. See also did the R107 come with a manual.
3-speed vs 4-speed
The three-speed in the 450SL has a tall first gear and no overdrive-style top gear, so it revs higher on the highway. The four-speed in the 380SL and 560SL gives better acceleration from rest and lower cruising rpm. The four-speed may start in second; see why it starts in second.
How to identify yours
- Data card: lists the transmission code.
- Transmission tag or stamp: on the transmission case, often on the left side or near the rear. The number begins with 722.
- Selector: a four-speed selector usually shows P-R-N-D-3-2 (or similar); a three-speed shows P-R-N-D-S-L or P-R-N-D-2-1, depending on year.
Fluid and filter differences
All use ATF of the type listed in the Mercedes fluid specs for your year; many owners now use modern Dexron-type fluids approved for these transmissions. The pan, filter and capacity differ between three- and four-speed units, and some have a torque converter drain plug. Buy the filter kit for your transmission code. Details in transmission fluid.
Manual options outside the US
European 280SL, 350SL, 500SL and later 300SL cars could be ordered with a four- or five-speed manual depending on year. US cars were automatic only.
Quick answers
- Can I swap a four-speed into a 450SL? It has been done, but it requires matching parts and adjustment; plan carefully.
- Is the 722.3 reliable? Yes, when the fluid is maintained and the modulator and cable are adjusted.
- Where is the transmission number stamped? On the transmission case or a tag; it starts with 722.
- Do 3-speed and 4-speed cars use the same filter? No, buy the filter for your transmission code.
- Is the manual-transmission R107 rare in the US? Very; US cars were sold as automatics.
- Does the 4-speed improve economy? Yes, together with taller axle ratios on later cars.
