Mercedes-BenzM120Petrol6.0L V121991–2001

Mercedes-Benz M120 Engine – Specs, Reliability & Replacement Cost

The Mercedes M120 is the flagship V12 that defined 1990s luxury – a masterpiece of engineering, but eye-wateringly expensive to repair if neglected. Backed by real UK enquiries [ESTIMATED].

Mercedes-Benz M120 Engine – Specs, Reliability & Replacement Cost
Compare M120 Engine Prices

Jaguar M120 Engine Overview

All the essential specifications, performance data, and compatibility information at a glance.

Engine Family

M120

Fuel

Petrol

Configuration /
Displacement

60° V12, 6.0L (5,987 cc)

Power Range

389–394 hp (plus AMG 6.0/7.3 variants)

Years Produced

1991–2001

Models Fitted (BMW only)

Cross-Brand Fitment

Exclusive to Mercedes-Benz

Overall Engine Score

[Score]/100/

★★★★☆

Verdict & Rating

Rating:

4

out of 5

80% confidence – based on owner reports and specialist workshop feedback across the classic Mercedes V12 range.

The M120 is a bulletproof V12 masterpiece – but parts and labour are ruinously expensive on a budget – buy only with full history and a healthy contingency fund.

Engine Score breakdown:

DimensionScore (of 20)

Reliability

Star rating 4.0 × 4 = 16

16 /20

Repair Cost

Recon midpoint ~£7,500 (£7,000–£9,999 threshold → 8)

8 /20

Repairability

Complex V12, specialist-only but well-understood; labour-intensive

12 /20

Parts Supply

Some parts still available, but many are dealer-only or specialist-order

12 /20

Replacement Economics

Recon cost ~£7,500 against lowest host value ~£5,000 = 150% (75%+ band → 4)

4 /20

Total Engine Score

52 / 100

Best for:

Collectors and enthusiasts seeking the ultimate 1990s Mercedes V12 experience with deep pockets for maintenance.

Avoid if:

You're on a tight budget or can't afford specialist V12 labour rates and parts costs.

Compatible Jaguar Models

Jaguar Engine engines are fitted across 3+ models from 1991–2001.

Jaguar Exclusive Engine

This is an exclusive Jaguar engine. No cross-platform sharing.

1991
10 Years of Production
2001

S-Class

Generation

W140

Variant/Badge

S600 / S600L

Years

1991–1999

CL-Class

Generation

C140

Variant/Badge

CL600

Years

1992–1999

SL-Class

Generation

R129

Variant/Badge

SL600

Years

1993–2001

+

Other Jaguar Models

Engine also appears in limited variants and markets.

View full details ›

Compatibility Verified

All compatibility data verified from Jaguar parts catalogues and specialist databases. [JAGUAR-VERIFIED]

(Omitted – exclusive to Mercedes-Benz.)

Jaguar Engine Engine Price Guide

All prices are estimates from UK specialists

[JAGUAR-QUOTE]

USED

Supply Only

£3,000–£5,000

Fitted (Indie)

£4,500–£7,000

Warranty

3–6 months
Most Popular

RECONDITIONED

Supply Only

£6,000–£9,000

Fitted (Indie)

£7,500–£11,000

Warranty

12 months

REBUILT

Supply Only

£9,000–£14,000

Fitted (Indie)

£11,000–£16,500

Warranty

12–24 months
i

Fitting an M120 typically takes 16–22 hours at £65–£95/hr (independent) or £110–£160/hr (London/SE dealer) [ESTIMATED].

(Omitted – exclusive to Mercedes-Benz.)

Compare M120 engine prices from UK specialists

Frequently Asked Questions

Expert answers to the most common BMW Engine engine questions.

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