Mercedes-Benz R107 SL Specs and Maintenance: Every Engine, the Brakes, and What to Service
The R107 ran for eighteen model years with eight US and Euro engine branches, three automatics, and two body styles — the R107 roadster and the C107 SLC coupe, which rides on a wheelbase 360 mm longer and was built 1972–1981. Everything below comes from the R107 guide's Stock Specs, Engine Maintenance, Brakes, Tires and Wheels, Differentials, Parts Interchange, and How-To Links tabs, as listed in the guide on October 18, 2026. Where the guide flags a conflict between sources, it is flagged here too.
1. Engines by era
| Model | Years | Engine | Power |
|---|---|---|---|
| 350SL (US, actually 4.5L) | 1972 | M117 V8, 4,520 cc, 8.0:1 | 190 hp @ 4,750 rpm, 240 lb-ft @ 3,000 rpm (SAE net) |
| 450SL / 450SLC (US) | 1973–1980 | M117 V8, 4,520 cc, 8.0:1 | 190 hp early, 180 hp later; 240 lb-ft early, 220 lb-ft later (SAE net) |
| 450SL / 450SLC (Euro) | 1973–1980 | M117 V8, 4,520 cc | 225 hp DIN; 0–100 km/h 8.8 s, top speed 215 km/h |
| 350SL / 350SLC (Euro) | 1971–1980 | M116 V8, 3,499 cc, iron block, 9.0:1 | 200 hp DIN |
| 280SL / 280SLC (Euro) | 1974–1985 | M110 DOHC inline-6, 2,746 cc | 185 hp DIN; 0–100 km/h 10.1 s, top speed 205 km/h |
| 450SLC 5.0 (Euro) | 1978–1980 | M117 V8, 5,025 cc | 240 hp DIN — WRC homologation special |
| 380SL / 380SLC (US) | 1981–1985 | M116 all-alloy V8, 3,839 cc, 8.3:1 | 155 hp @ 4,750 rpm, 196 lb-ft @ 2,750 rpm (SAE net) |
| 380SL / 380SLC (Euro) | 1980–1985 | M116 all-alloy V8, 3,839 cc | 218 hp DIN |
| 500SL / 500SLC (Euro) | 1980–1989 | M117 V8, 4,973 cc | 240–245 hp DIN, KE-Jetronic from Sept 1985; 0–60 mph 7.4 s, top speed 225 km/h (140 mph) |
| 420SL (Euro) | 1985–1989 | M116 V8, 4,196 cc | 215–218 hp DIN — replaced the 380SL |
| 300SL (Euro) | 1985–1989 | M103 SOHC inline-6, 2,962 cc | 185–188 hp DIN — replaced the 280SL |
| 560SL (US) | 1986–1989 | M117 V8, 5,547 cc, 9.0:1 | 227 hp @ 5,200 rpm, 287 lb-ft @ 3,500 rpm (SAE net); 0–60 mph ~7.1 s |
Two notes from the guide: the 380SL torque figure conflicts between sources — 196 lb-ft at 2,750 rpm in the spec table, with some sources quoting 232 lb-ft — and the US 350SL badge is a misnomer, since the 1972 US car carries the 4.5L M117 for emissions. Transmissions are all automatics: the 3-speed (W3A 040 / 722.0) on the 1972 350SL; the 3-speed auto (722.0/722.2) on 450SL cars with the 4-speed auto (722.3) phased in around 1977–1978; and the 4-speed automatic (722.3) on the 560SL. The roadster is a 2-seat convertible with a manual soft top and a removable hardtop, with optional rear jump seats on Euro cars; the SLC is a 2+2 fixed-roof coupe.
2. Rear-axle ratios and the limited-slip option
Ratios vary by model and year, and the guide's data is community-sourced — check the data card or the stamping on the diff housing rather than assuming. As listed in the guide: the 450SL runs 3.07:1 (US) or 3.06:1 (Euro), the Euro ratio slightly taller for better highway manners; the 380SL runs 2.47:1, tall economy gearing that cruises relaxed and is slower off the line; and the 560SL runs 2.65:1, the same ratio as the 6.9 and the best all-round compromise in the guide's words. A limited-slip differential was a factory option — check the data card for the LSD option code; it is rare and desirable, and AMG 6.0 conversions ran LSD. Rear-axle ratios for other models are not in the guide's data: the Differentials tab lists them as community data pending, so they are left out rather than guessed. Diff mounts wear and clunk on throttle lift — inspect at service and replace with the subframe bushings as a set.
3. Service intervals
These are the guide's maintenance intervals, as listed in the guide — several are recommendations from vintage-Mercedes mechanics rather than factory figures, and they are labeled as such:
- Timing chain and guides: inspect via the valve cover; replace upper guide rails if not done in the last 15 years. Single-row 380SL: every ~40,000 miles if not converted; general rule ~60,000 miles. A guides-only DIY kit runs about $80, as listed in the guide. MercedesSource calls the plastic guides the #1 V8 failure point.
- Valve adjustment (early V8, mechanical): every 10,000–12,000 miles, on M116/M117 engines through 1976 with ball adjusters. Shop cost about $200–400, as listed in the guide — and the most neglected service per MercedesSource.
- Engine oil: 3,000-mile changes recommended by vintage-MB mechanics. 15W-40 or 20W-50, high-zinc for flat-tappet V8s. About $60 DIY, as listed in the guide.
- Transmission fluid and filter (722.x): about every 30,000 miles. Check front pump seal leaks; delayed reverse means pump wear.
- Coolant: every 2–3 years. Poor coolant corrodes Chrysler-servo cars internally.
- Brake fluid: every 2 years. ABS units need clean fluid.
- Differential fluid: inspect/change about every 30,000 miles. Check the optional LSD.
- Fuel filter and K-Jet pressures: check control and system pressures at any drivability complaint. Replace the fuel filter regularly and check the rear fuel hoses for wetness.
4. Brakes and part numbers
Vented front discs and solid rear discs with 2-piston calipers, as listed in the guide. ABS was optional from 1980 — the first US car with electronic ABS — and standard on the 560SL. The documented big-brake upgrade path is the 560SL's 4-piston calipers and 284 mm rotors for earlier cars, but it is NOT a direct bolt-on: it requires 15-inch wheels minimum AND different steering knuckles. Part numbers, as listed in the guide's Brakes tab and How-To Links (SLSHOP fitment): early 2-piston front calipers, ATE A1074200283, fitting 280/350/450/380 SL/SLC up to the chassis break points; 560SL 4-piston front calipers, ATE A1073320401 (left) and A1073320402 (right), 560SL-specific, with steering knuckles that differ from the 450SL; Brembo front brake pads A0014209920, which cross-fit the R107 plus the W116, W123, and W126; late front rotors (300/420/500/560), OEM A1244211612, vented, fitting chassis 107.041/046/047/048; and the brake booster, ATE T52 (0024306830), fitting all R107 SL/SLC cars. Rear brake pads cross-list for the 280SL/450SL/380SL/560SL plus the W116, W123, and W126. Flush brake fluid every 2 years.
5. Wheels and tires
Factory fitment: 350SL/450SL and 280SL cars run 205/70VR14 on 6.5Jx14 bundt (baroque) alloy or steel wheels, 5x112 bolt pattern; the 560SL (1986–1989) runs 205/65VR15 on 15-inch alloys, at 30 psi front / 35 psi rear. The most popular period-correct upgrade is 15-inch wheels on an early car — 205/65R15 on 15-inch bundt or 560SL wheels — and it is also the upgrade needed for the 560SL brake swap. Period 16-inch AMG/Penta-style wheels are a sportier stance but need the offset checked against the arches. The 560SL "manhole cover" 15x7 alloys are a popular retrofit to earlier cars. The guide's owner recommendation for the early cars is the Blockley 205/70VR14 as the correct-pattern tire. Check tire age, not just tread: the guide notes 2001-dated tires seen on for-sale cars, and tires over 6–10 years old should be replaced regardless of tread. The spare is full-size, trunk-mounted, with a jack and tool kit — missing tools signal neglect.
6. Parts interchange: what swaps from other chassis
The R107 shares heavily with the sedans of its era, all at high confidence in the guide's Parts Interchange tab: timing chain kits, guides, mounts, and ignition parts from the W116 and W126 with the same M116/M117 engines; rear brake pads from the W116, W123, and W126 (same pad shape); the steering coupling from the W108/W114/W115/W116/W123/W126, fitting the 1968–1991 chassis range; and rear trailing-arm bushings from the W114/115/107/116/ 123/126, also 1968–1991. The 560SL brake swap onto earlier R107s is listed with its condition: 4-piston calipers and 284 mm rotors require 15-inch wheels and different steering knuckles. Euro bumpers, headlights, and taillights are direct-fit Euro parts and the most popular cosmetic conversion on US cars. One caution from the guide's How-To Links (PeachParts): 560SL versus earlier-car interchange differs for steering boxes, brakes, wheels, and tie rods, and SLC versus SL body parts differ — check before buying.
7. How-to links worth bookmarking
The guide's How-To Links tab collects the threads that match the jobs above: the Pelican Parts timing-chain and camshaft sprocket replacement (a 30-minute job covering tensioner, guides, and sprocket) and the crank-hub removal that is the prerequisite for guide-rail and chain work; the FCP Euro article on 107 subframe failure and the gusset fix; the BenzWorld/W116 forum thread on the 380SL single- vs double-row chain (1981–1983 single-row prone to snap, factory double-row from 1984, conversion about $2,500–3,000); the MercedesSource on-demand videos for K-Jetronic fuel-pressure testing on the M110/R107; the W116 forum power-window regulator fix that applies to the R107 (the regulator bends from dried grease — straighten, clean, and re-lube with white lithium); and the ClassicMerc article on automatic antenna operation (motor noise but no movement means clean the mast; check the fuse and switch). The guide also carries a Tier 2 RockAuto catalog for the R107 (snapshot October 30, 2026) covering 28 US-market year/model branches from 1972 to 1989 — it carries no 1971 R107 (the catalog's 1971 280SL is the W113 Pagoda) and no Euro models, so Euro owners' closest coverage is the same-era US branch.
What this page does not cover: rear-axle ratios for models other than the 450SL, 380SL, and 560SL (the guide lists them as community data pending), and torque figures beyond the spec table — the 380SL torque conflict (196 vs 232 lb-ft) is flagged where it appears. The guide does not state those, so they are left out rather than guessed.
Open the full interactive R107 guide for the complete engine maintenance table, stock specs, brakes, tires and wheels, differentials, and current for-sale listings.
Compiled from the Cerch Garage Mercedes-Benz R107 SL (1971–1989) guide (Stock Specs, Engine Maintenance, Brakes, Tires and Wheels, Differentials, Parts Interchange, and How-To Links tabs), as listed in the guide on October 18, 2026, plus the guide's Tier 2 RockAuto catalog (snapshot October 30, 2026). Prices and costs are as listed in the guide and change; verify before buying anything.