BMW M47, M57 and M67 Diesel Engines

BMW M57 diesel engine

M57TU in the super quick E46 330d.

Chronology

The M51 and M41 diesels had broken new ground for BMW and set new standards, but yet again it was time to raise the bar. Against this background the M47 four cylinder and M57 six cylinder diesels were launched from 1998, although introduction dates to the E34 three, E38 seven and E39 five series differed slightly.

The 330d and 530d were ground breaking models for high performance diesel.In 2000 Jenson button was caught by French Police doing over 140mph in a 330d, the BMW marketing department should have paid his fine. In the UK and europe a two litre diesel is now the engine of choice for many drivers, the M47 was the engine that made this the desirable choice. The older M41 was good, but at 1.7 and with older technology it was way behind the M47. When the M47 was launched it had the highest power per litre of any diesel ever sold by anyone in a production car (70bhp/litre). This generations of diesels is why 50% of UK cars don't use petrol any more, drivers bought them as fast as BMW could make them.

In 2002 the M57TU (sometimes called M57N) upgrade started production, it boasted roughly 20 more horses and a substantial 50lb/ft more torque. For the first time a twin turbo version was offered in the E60 535d (E90 335d came later) and made a whopping 268bhp and 410lb/ft of torque. In the UK this engine was only available with an automatic gearbox.

A final M57TU2D30 (sometimes called M57N2) came out in late 2006, initially on the E60/E61 five series but eventually on the E65 730d, X3, X5, X6 and the new E90 three series.

The two litre M47 saw initial service not just on the usual three and five series but also on the Land Rover Freelander, Rover 75 and MG ZT. For these it was adapted to front wheel drive installation. An M47TU was available from late 2001 on the X3 and gained 50cc along the way due to a longer stroke, it was regarded by reviewers as an big upgrade on the M47. A final tweaking in 2004 gave us the M47TU2.

The V8 M67 started out as a 3.9 in the 1998 E38 740d. This was BMW's fist V8 diesel and for the time it's 410lb/ft was impressive although it was later equaled by the twin turbo version of the M57TU 3.0. For the heavier E65 740d in 2002 a bit more was required and an M67TU replied with 5% more power and 7% more torque. A final 4.4 litre M67 was sold in 2005 for the now face lifted E65 745d and made 300bhp / 516lb/ft rising to 330bhp / 552lb/ft for 2006.

Don't get too hung up on power figures as a good proportion of these cars have been chipped by their owners, BMW dealers even offered such a service which didn't void the warranty. Even a mildly chipped 320d can make more torque than an E46 //M3. On a used diesel performance can vary considerably depending on how clean the engine is internally which in turn depends on how well it was serviced and driven. In particular short journeys are bad for these engines.

There were a confusing variety of diesels deployed over the years and I'm sure dealer parts departments have a few gray hairs as a result. After sorting out the details on this page I certainly earned a beer.

 

BMW M47 diesel engine

M47D20TU crammed into an E46 320d.

Design

Unlike the older M41/M51 diesels these were 4 valve per cylinder units which also used very high pressure fuel injection. The M47 had a 1750 bar fuel pressure distributor pump but the M57 used a common rail system more suited to a larger six cylinder engine.

The low friction roller activated valve technology pioneered on the M44 was used. In a highly innovative concept one of the two inlet tracts for each cylinder was designed in a spiral form to induce turbulence in the cylinder and improve combustion efficiency.

Electronically controlled variable incidence turbos were developed. These used vanes on the turbo's input to direct the angle at which the gases met the turbine vanes and thus optimise operation for various loads.

The M47 was initially a 1951cc unit but for the launch of the X3 in late 2001 this was upped to 1995cc in the M47TU by means of a longer stroke. It was this M47TU which introduced the infamous swirl flaps (see the Problems section below) to make the engine warm up faster and increase low end torque in a similar way to the petrol DISA system by altering the intake tract length.

A special M47R was built for Rover. It had common rail injection and a different turbo, these lead to higher temperatures and other problems. The Rover unit was costlier, heavier and less efficient as a result.

The M57TU used the same stroke change made to the M47TU and grew by 70cc as a result. It also had an improved Garrett turbo and of course the dreaded swirl flaps. Confusingly some manual cars with M57TUs didn't get the swirl flaps. Depending on model year swirl flaps may be electrically or vacuum operated. On these later engines a few extra sensors were added as inputs to the DME for EU4 emission compliance.

The M67 V8 had a cast iron block using a 98mm piston spacing as on the aluminium petrol M60 V8 and unlike the 91mm spacing on inline engines. It had twin electronically controlled turbos, common rail injection and twin MAFs with two intake tracts and air boxes. It used the same sintered steel conrods as the M60 which were snapped instead of being machined at the big and little ends to ensure a better fit!

BMW M67 diesel engine

M67 V8 diesel with intercooler.

Variants

Code Size Power
bhp@rpm
Torque
lb/ft@rpm
BHP/
litre
Torque/
litre
Manufactured Bore x
Stroke
Timing Weight
(kg)
VANOS Used in
M47 2.0 detuned

2.0

114 @ 4000
136 @ 4000
195 @ ?
207 @ 1750
57
68
98
104
1998 - 2001 84x88 Chain 117 No 118d, 318d
120d, 320d
M47TU 2.0 detuned

2.0

114 @ 4000
148 @ 4000
207 @ ?
243 @ 1750
57
74
103
122
2001 - 2004 84x90 Chain 117 No 118d, 318d
120d, 320d
M47TU2 2.0 detuned

2.0

121 @ 4000
161 @ 4000
207 @ ?
251 @ 1750
60
80
103
126
2004 - 2005 84x90 Chain 117 No 118d, 318d
120d, 320d
M57 2.5

3.0

164 @ 4000

184-193 @ 4000

260 @ 2000-2500

290-300 @ 1750-3250

65.6

60.3

104

96.7

1999 - 2002 80x82.8

84x88

Chain 168 No E46, E38, E39
M57TU 2.5

3.0

177 @ 4000

204-215 @ 4000

300 @ 2000-2750

350-370 @ 1750-3250

73

73

120

123

2002 - 2003 80x82.8

84x90

Chain 168 No E46, E38, E60
M57TU
twin turbo
3.0

272 @ 4000

410 @ 2000-2250

73

73

120

123

2004 ?

84x90

Chain 168 No 535d
M57TU2 3.0 228 @ 4400 370 @ 2000-3250 91 138 2004 - 2006 84x90 Chain ? No E90, E65, E60
M57TU2
twin turbo
3.0 282 @ 4000 430 @ 2000-2250 94 143 2004 - 2006 84x90 Chain ? No 335d, 535d
M67
M67TU
M67D44
M67D44
3.9
3.9
4.4
4.4
234 @ 4000
254 @ 4000
300 @ 4000
330 @ 3800
413 @ 2000
442 @ 2000
516
552
60
65
68
75
105
113
117
125
1999
2002
2005
2006
84x87
84x87
87x93
87x83
Chain ? No E38 740d
E65 740d
E65 745d
E65 745d

 

<BMW M57 diesel engine

An early metal swirl flap in the process of falling apart.

Problems

If you're thinking of buying a diesel BMW check out the petrol vs diesel page first.

Firstly, all modern diesels have these sort of problems it's not just BMWs. Other engines clog up with soot, other manufacturers used swirl flaps. If anything a BMW engine is more likely to get looked after than one in a cheaper car.

The enemy of all diesel engines is carbon deposits. The EGR valve which recirculates dirt through the engine to reduce emissions makes this worse. The first step for any poorly running diesel is to strip down the entire intake tract and clean it, especially the EGR valve. Many folk blank off the EGR valve but this may not be legal where you live.

These engines have an internal breather filter, sort of like a second air filter. If the main air filter is dirty then it's time to change both. If you buy a used car just assume the breather filter needs changing and the EGR needs cleaning. From 2004 some got a vortex filter instead.

Diesels take longer to warm up than a petrol engine and if run cold will get dirty very quickly as they don't burn off soot deposits. For this reason you really want to avoid cars that have been used only for lots of short journeys. They will seldom have reached normal operating temperature and will be filthy inside.

The other worry is the turbo, the only thing you can do to prolong it's life is to use good oil and change it at the correct intervals. Never let the level run low and let the car cool down gradually after very hard driving.

On cars up to late 2003 the variable turbo incidence is controlled by a vacuum system. The hoses can clog or collapse resulting in poor performance.

<BMW M57 diesel engine

M47 breather filter, this needs to be changed regularly.

I've heard of injectors becoming stuck and being a massive pain to remove. Only a problem if one fails of course.

Swirl flaps, the nasty problem. Early ones were made of metal and the fixing holding the plate to its shaft can break resulting in bits going into the cylinder and killing the engine. A lot were replaced under warranty and not always at high mileages. Later flaps were made of plastic and had thicker shafts. For the full story and a cheap delete kit visit www.swirlflaps.co.uk

Depending on year and market your car might have a Diesel Particle Filter (DPF). These store diesel soot and burn it off at high temperatures. Which is a problem if the car does lots of short journeys and never gets warm (seeing a pattern here?). If it clogs up it's an MoT failure and the car will drive poorly. Removing it may be illegal and a new one can be very expensive. All modern diesels have these, not just BMWs.

These engines are often chipped by their owners. Generally this isn't a bad thing and can have excellent results. But beware of used cars where things have been taken a bit too far.

If you drive this like a high performance engine it will drink fuel accordingly. For good economy it's best to be gentle and use the cruise control a lot.

<BMW M57 diesel engine

EGR valve clogged with soot from an M47.