Which BMW Has the S85 V10 Engine? Full M5 and M6 Breakdown
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There is only one BMW road car engine with ten cylinders. One. The S85. BMW built it between 2005 and 2010, fitted it to exactly four models, and then never made anything quite like it again. The engines that followed were turbocharged, smaller, and objectively faster in many situations. None of them sounds like this.
If you are searching for an S85 engine for sale, trying to identify whether a car you are looking at has one, or just trying to understand what all the fuss is about, this guide covers the full picture. Which cars it went into, what makes it special, what goes wrong, and what to check before buying.
What Is the BMW S85 Engine?
The S85 is a 5.0-litre naturally aspirated V10 petrol engine. No turbochargers. No supercharger. Just ten cylinders, individual throttle bodies for each one, and an 8,250rpm redline that BMW arrived at partly by drawing on its experience building Formula One engines through the BMW Sauber F1 programme in the early 2000s.
It produces 500hp at 7,750rpm and 383lb-ft of torque at 6,100rpm. Those numbers look modest on paper by 2020s standards. Turbocharged four-cylinders produce similar outputs today. What the S85 does differently is how it gets there. The power builds progressively, smoothly, with the engine note changing character all the way through the rev range. By 6,000rpm it sounds unlike anything else that has worn a BMW badge.
The 10 individual throttle bodies, one per cylinder, are partly responsible for both the character and the complexity. Each one is motor-driven and responds to throttle inputs almost instantaneously. They are also a known maintenance item, and one that has stung S85 owners who did not know what they were buying into.
Which BMWs Have the S85 Engine?
The S85 went into four cars, all built on the E6x platform. That is it. No other BMW road car has ever used it.
BMW M5 — E60 (saloon, 2005–2010)
The E60 M5 is the car most people associate with the S85. It was the first production saloon in the world to come with a V10 engine from the factory. When it launched in 2005, it produced 500hp from a naturally aspirated engine in a four-door saloon body, which was extraordinary at the time, and still commands respect now.
Early E60 M5s came only with the SMG III single-clutch automated manual gearbox, which divided opinion sharply. In automatic mode it was jerky and slow by modern standards. Operated with the paddles in manual mode, it was fast and engaging. BMW introduced a six-speed manual option in 2007, and most enthusiasts consider the manual car the one to have.
Production ran from 2005 to 2010. Total production numbers were relatively small by mainstream BMW standards, which is why clean low-mileage examples have been climbing in value in recent years.
BMW M5 Touring — E61 (estate, 2006–2007)
The E61 M5 Touring is the rarest S85-powered car. BMW built only 1,025 of them across a very short production window between 2006 and 2007, making it one of the rarest M cars from this era. It is a V10-engined estate car, practical by packaging, completely impractical by running costs, and it is exactly as ridiculous as that sounds in the best possible way.
The Touring was only available with the SMG gearbox, which makes finding the right example slightly simpler. There is no manual versus automatic choice to make. Values have risen significantly as collectors have recognised how few exist.
BMW M6 — E63 (coupé, 2005–2010)
The E63 M6 uses the same S85 engine in the same state of tune as the M5. Same 500hp, same gearbox options (SMG initially, manual from 2007), same maintenance requirements. The M6 body is lower and wider than the M5, with a different suspension setup that gives a slightly different character on the road, firmer, more GT than sports saloon.
Production of the E63 ran alongside the E60 M5 through to 2010. It is generally considered slightly less collectable than the M5 by the market, which means it can represent better value for someone who wants the S85 experience without the premium that the M5 now commands.
BMW M6 Cabriolet — E64 (convertible, 2006–2010)
The E64 M6 Cabriolet brings the same engine in a four-seat drop-top body. The additional weight of the electric roof mechanism means it is the slowest of the four S85 cars, though the difference is not dramatic. It only ever came with the SMG gearbox. If you want an S85 in an open car, this is your only option from the factory.
S85 Engine Problems — What Actually Goes Wrong
The S85 has a reputation. Some of it is deserved. Some of it has been exaggerated by people who have heard the horror stories without understanding that most of the serious failures happen to BMW engines that were not looked after properly. Here is what actually goes wrong.
Rod bearings — the one everyone talks about
Rod bearing wear is the S85's defining reliability concern, and it is real. The big-end bearings that connect the connecting rods to the BMW crankshaft can wear prematurely, particularly on engines that have been run on incorrect oil or at high revs before reaching operating temperature. Once worn bearings start knocking, the damage accelerates quickly. An engine that develops a knock from rod bearing wear is usually not far from catastrophic failure if driven hard.
The preventative measure is straightforward in principle: replace the rod bearings before they fail. Most S85 specialists recommend doing this proactively before 80,000 miles, or buying a car that already has documented bearing replacement. It is an expensive job, typically £2,000 to £3,500 at a specialist, but considerably less expensive than an engine rebuild or replacement.
The other critical factor is oil. The S85 requires 10W-60 fully synthetic oil. Not 5W-40, not whatever the nearest Halfords has on offer. 10W-60. The higher viscosity maintains oil film strength at the extreme operating temperatures the engine reaches when used as intended. Running the engine on thinner oil accelerates bearing wear significantly. Any S85 with a history of incorrect oil is a risk.
Before buying any S85-powered car, ask specifically about rod bearing history. If the bearings have been done with documented evidence, that is a major positive. If the car has covered more than 70,000 to 80,000 miles and there is no record of bearing work, treat it as an upcoming cost and factor it into the price.
Throttle actuators
Each of the ten individual throttle bodies is controlled by its own electric actuator motor. These motors wear over time, and when they do, the symptoms are uneven idle, hesitation under load, and in some cases fault codes across multiple cylinders. Replacement is expensive because there are ten of them, and while they do not always all fail at once, replacing one often prompts finding several more that are marginal.
A new set of ten actuators from BMW is a significant bill. Used BMW actuators from documented donor cars are the approach most S85 owners and specialists take when addressing this fault. A pre-purchase diagnostic scan will show any stored throttle actuator fault codes and give you an indication of how many have already been flagged.
VANOS — variable valve timing
The S85 uses BMW's double-VANOS variable valve timing system on both banks of cylinders. VANOS solenoid wear is a known issue that typically appears between 60,000 and 80,000 miles. Symptoms include rough running at idle, loss of power across the rev range, and specific fault codes for VANOS function. Solenoid replacement is a standard workshop job and not catastrophically expensive, but it is one of several maintenance items that stack up on a high-mileage S85.
SMG gearbox
The SMG III gearbox fitted to most S85 cars is not an engine issue, but it is one of the most common reasons E60 M5 and E63 M6 owners end up with an expensive repair. The SMG pump, a hydraulic pump that operates the clutch and gear changes, fails on many cars, and replacement is costly. Cars that have had the SMG converted to a proper six-speed manual by a specialist are considered more desirable by many buyers, though the conversion itself is a significant piece of work.
Before buying any SMG-equipped S85 car, test the gearbox thoroughly in all modes. Harsh changes, refusal to engage a gear, or unusual noises from the transmission all warrant investigation.
Oil consumption
The S85 consumes oil, particularly when driven as it is meant to be driven. This is not a defect. It is expected behaviour from a high-revving motorsport-derived engine. Owners need to check the oil level regularly rather than assuming it will stay at the full mark between services. Running low on oil on an S85 with rod bearing concerns is not a situation you want to find yourself in.
What to Check Before Buying an S85-Powered BMW
An S85 car is not a car you buy on impulse. It rewards research, proper inspection, and ideally a specialist's opinion before money changes hands.
Rod bearing history. The single most important question. Has the work been done? When? By whom? Is there paperwork? A car with documented bearing replacement by a known specialist is worth more than one without, regardless of mileage.
Full service history with correct oil. Every service record should show 10W-60 oil. A gap in the history, or records showing a different viscosity, introduces uncertainty about the engine's bearing condition.
Diagnostic scan. A scan of the engine management system before purchase will show stored fault codes across all ten throttle actuator channels, VANOS function, and any other stored faults the car has accumulated. Do not skip this.
Cold start. Start the engine from fully cold. Listen carefully for any knocking or tapping from the engine in the first 30 seconds. Rod bearing knock on the S85 is a deep, rhythmic knock that increases with revs. If you hear anything like this, walk away.
SMG condition. If the car has the SMG gearbox, test every gear in both automatic and manual paddle modes. Test from cold and when warm. The SMG pump failure often presents as inconsistent changes or complete refusal to select a gear.
Specialist inspection. More than on almost any other car, have an independent BMW specialist look at an S85-powered car before you commit. An hour of specialist time is cheap relative to what the engine costs to repair.
The E61 M5 Touring is the rarest S85 car with only 1,025 built. If you are looking at one, values have risen sharply, and provenance matters enormously. Get the full documented history if at all possible.
Frequently Asked Questions
Which BMW has the V10 engine?
Only four BMW road cars ever had the V10 S85 engine: the E60 M5 saloon, the E61 M5 Touring, the E63 M6 coupé, and the E64 M6 Cabriolet. All were produced between 2005 and 2010.
How much does an S85 engine cost to buy?
Used S85 engines are not common and prices reflect that. A documented low-mileage unit with known history is considerably more expensive than a no-history example. Expect to pay anywhere from £4,000 to £10,000 or more for a decent used S85 engine for sale, depending on mileage, bearing history, and condition.
Is the S85 engine reliable?
It depends almost entirely on how it has been maintained. An S85 with documented rod bearing replacement, a full service history using correct 10W-60 oil, and functioning throttle actuators can be a solid engine for a driver who understands its needs. An S85 with unknown history and 100,000 miles on it is a risk. The engine does not forgive neglect.
What oil does the S85 engine take?
10W-60 fully synthetic oil. This is not negotiable. The S85 was designed around this viscosity and the higher oil film strength it provides at operating temperature. Running a lower viscosity oil accelerates rod bearing wear. Every service should show 10W-60.
What is the difference between the M5 E60 and M6 E63 S85 engine?
They are the same engine in the same state of tune. Both produce 500hp, both share the same maintenance requirements and failure points. The difference is in the car around the engine. The M5 is a four-door saloon, the M6 a two-door coupé with a lower, wider body and firmer suspension. The M5 is generally considered more collectable.
How many S85 engines were made?
BMW produced the S85 from 2005 to 2010 across all four models. Exact production numbers for the engine itself are not publicly documented, but the number of cars is known. The rarest is the E61 M5 Touring at 1,025 units worldwide. The E60 M5 was the highest-volume car of the group.
Disclaimer: This article covers the BMW S85 V10 engine, its applications, known faults, and buying considerations. Reliability information is based on widely reported owner and independent workshop experience. Always have any S85-powered car inspected by a qualified BMW specialist before purchase.
