6G75 Mivec / GDi 3.8 Engine Specs, Problems, Reliability

The Mitsubishi 6G75 3.8-liter V6 engine was produced at the Kyoto plant from 2002 to 2021 and was installed on such popular concern models as the Endeavor, Pajero, Galant or Eclipse. There are three versions of the engine: regular, with MIVEC phase shifters and GDI direct injection.

In 2002, the most voluminous engine of the 6G7 series debuted on the restyled Pajero 3. It was a completely ordinary V-shaped engine with a cast-iron block and a 60 ° camber angle, distributed fuel injection, intake swirl flaps, timing belt drive. All versions of the engine had aluminum SOHC heads for 24 valves with hydraulic lifters.

In 2005, a more powerful version of the internal combustion engine with the proprietary MIVEC phase control system appeared, and for a long time the company sold both modifications of this engine in parallel. In the Japanese market, they offered a rare version of this engine with GDi direct fuel injection.

Read Also: 4D56 / D4BH / D4BF 2.5 Engine Specs, Problems, Reliability

The engine uses a 24-valve SOHC single-shaft circuit, which has two versions:

  • with Mivec;
  • with GDI.

Depending on this, the versions differ in power performance, compression and other values.

6G75 Engine Specifications

ProductionKyoto engine plant
Engine brand6G7/Cyclone V6
Release years2003-present
Block materialcast iron
Supply systeminjector
Type ofV-shaped
Number of cylinders6
Valves per cylinderfour
Piston stroke, mm90
Cylinder diameter, mm95
Compression ratio9.810

(GDI)
Engine volume, cc3828
Engine power, hp / rpm235-265/5250-5750

218/5000(GDI)

(see description)
Torque, Nm/rpm329-339/2750-4000

339/3750 (GDI)

(see description)
Fuel95-98
Environmental regulations
Engine weight, kg~200 (12V)
Fuel consumption, l / 100 km (for Pajero 4)
– city
– highway
– mixed

17.7

11.2
13.5
Oil consumption, g/1000 kmup to 1000
Engine oil0W-30

0W-40


5W-30


5W-40


5W-50


10W-30


10W-40
How much oil is in the engine, l4.9
Oil change is carried out, km7000-10000
Operating temperature of the engine, hail.
Engine resource, thousand km
– according to the plant
 – in practice



400+
Tuning, HP
— potential
— without loss of resource


1000+

The engine was installedMitsubishi Galant
Mitsubishi Eclipse 4
Mitsubishi Pajero/Montero
Mitsubishi 380

Mitsubishi Endeavor

6G75 Engine Performance Summary

Here, we will investigate the characteristics of this engine by referring to the data of the 6G75 type naturally aspirated engine installed in Mitsubishi’s V97W type Pajero Long Super-Exceed 2010/09 model.

mitsubishi PAJERO 6G75 Engine

Mitsubishi’s V97W type Pajero Long Super-Exceed

Vehicle modelCBA-V97W type
Car name & gradePajero
Long Super-Exceed
Engine model6G75
typeV-type 6 cylinder
Displacement3827cc
Inner diameter x stroke95.0mm x 90.0mm
Bore stroke ratio0.95
Single cylinder volume637.9cc
Compression ratio9.8
Intake methodNaturally aspirated
Fuel usedHigh octane gasoline
Maximum output252PS / 6000rpm
Maximum torque34.5kgm / 2750rpm

First of all, as a basic structure, the 6G75 type engine is a short stroke type engine with a bore (inner diameter) of 95.0 mm, a stroke (stroke) of 90.0 mm, and a bore stroke ratio of 0.95 (the piston diameter is larger than the stroke amount).

When the displacement and the number of cylinders are the same, the torque characteristics in the low rpm range are inferior to those of the long stroke type, and the engine is difficult to handle, but in the high rpm range, the filling efficiency is improved and the sliding resistance is also increased ( The output is expected to improve because it is minor (compared to the long stroke type).

Also, since the average piston speed can be suppressed even at the same rpm, the load on the engine tends to be reduced accordingly.

Among the models registered on this site, the oldest model equipped with the 6G75 type naturally inhaled engine is the 3rd generation Pajero [V77W type | 2005/11] released from 1999/09 , and the newest model is 2006. It is the 4th generation Pajero [V97W type | 2010/09] released from / 10, and all 3 models of NA car are registered and 0 car model of turbo / SC car are registered.

Evaluation from the viewpoint of transient characteristics and liter equivalent horsepower

Image of engine performance curve
6G75 engine performance curve diagram
Changes in horsepower132.4PS → 252PS
Transition of torque34.5kgm → 30.1kgm
Liter horsepower65.85PS / L
Liter torque9.0kgm / L

The reference vehicle of this time, Pajero’s V6 3827cc, high-octane gasoline specification naturally aspirated engine with a compression ratio of 9.8 produces a maximum output of 252 horsepower at 6000 rpm and a maximum torque of 34.5 kgm at 6000 rpm.

If you know the horsepower and the number of revolutions, you can know the torque, and if you know the torque and the number of revolutions, you can know the horsepower. The torque at 6000 rpm is 30.1kgm.

The horsepower per liter of displacement is 65.85PS / L and the torque is 9.0kgm / L, and the horsepower per cylinder (single cylinder volume 637.9cc) is 42.0PS and the torque is 5.8kgm.

When the 6G75 naturally aspirated engine is applied to a 10-step evaluation based on deviation values ​​aggregated from all NA vehicles registered on this site, the evaluation is ” standard ” with a converted horsepower of [ 5 ] and a converted torque of [ 4 ]. It is categorized as an engine with a typical output (bottom of the middle) .

By the way, among the models equipped with the 6G75 engine, the highest output was 252PS / 34.5kgm for the V97W Pajero, and the smallest was 219PS / 34.3kgm for the V77W Pajero.

Displacement increase, compression ratio increase, bore stroke ratio change

Normal displacement and compression ratio
BoreStrokeDisplacementCompression ratioB / S ratio
95.090.03827cc9.80.95
Displacement expansion by bore up
95.590.03868cc9.90.94
96.03909cc10.00.94
96.53949cc10.1.0.93
97.03990cc10.20.93
97.54032cc10.30.92
98.04073cc10.40.92
Displacement expansion by increasing stroke
95.091.03870cc9.90.96
92.03913cc10.00.97
93.03955cc10.1.0.98
94.03998cc10.20.99
95.04040cc10.31.00

There are three factors that determine the engine displacement: the number of cylinders, the bore diameter, and the stroke amount. By increasing or decreasing these, engines with various displacements are created.

Here, regardless of whether it is actually possible, the displacement when the piston diameter is expanded from the genuine 95.0 mm to 98.0 mm in 0.5 mm increments and when the stroke is extended from the genuine 90.0 mm to 95.0 mm in 1 mm increments. And, the change of the compression ratio when it is assumed that the volume of the combustion chamber does not change is listed.

* It is easy to say stroke up, but if you want to make a long stroke, you need a crankshaft and a compatible connecting rod, and if you can not divert it, you have to make it in one-off, so it is expensive anyway. It is a menu that requires considerable preparedness to put out.

Regarding the compression ratio, in most cases, the uneven capacity of the top surface of the piston changes as the diameter of the piston increases, so the compression ratio values ​​in the list do not match, but the displacement. Please enjoy the atmosphere that the compression ratio will naturally increase as you increase the size.

The B / S ratio is an abbreviation for the bore stroke ratio, and as the bore diameter is widened, the value becomes even smaller from 0.95, and the advantages and disadvantages of the short stroke type become more pronounced. In the case of the 6G75 engine, the ratio changes from 0.95 to 0.92 when the bore is increased by + 3.0mm from the genuine piston.

Increased displacement with engines with similar piston diameters

There are 4 engines with pistons that are close in size to the 6G75 type engine with a piston diameter of 95.0 mm, so as a side note, let’s calculate the displacement when the piston is diverted and the bore is raised.

Eg modelPiston diameterDisplacement
Nissan
ZD30 type
96.0mm
[+ 1.0mm]
3909cc
[+ 82cc]
Toyota
3L type
96.0mm
[+ 1.0mm]
3909cc
[+ 82cc]
Subaru
EJ22 type
96.9mm
[+ 1.9mm]
3982cc
[+ 155cc]
Subaru
EG33 type
96.9mm
[+ 1.9mm]
3982cc
[+ 155cc]

As engines with similar piston diameters, Nissan: ZD30 type 2953cc 96.0mm mounted on CWMGE25 type caravan coach, Toyota: 3L type 2779cc 96.0mm mounted on LH107G type high ace wagon, Subaru: BG7 type legacy touring wagon EJ22 type 2212cc 96.9mm, Subaru: CXD type Alcyone SVX EG33 type 3318cc 96.9mm, etc. are applicable.

(Although the number of people who find pleasure in such a quest has decreased) No matter how close the diameter is, there are factors such as the diameter of the piston pin, the height of the piston, and the convenience of valve recess, so if possible, the same manufacturer, If possible, if you choose the same fuel and the same intake method, and if possible, the one with a similar displacement, the possibility of genuine diversion may increase.

Average piston speed

strokeMaximum torque
2750rpm
Maximum output
6000 rpm
90.0mm8.2m / s18.0m / s
Rotation speed / minuteper secondSpeed
2000rpm6.0m / s22km / h
4000rpm12.0m / s43km / h
6000rpm18.0m / s65km / h
8000rpm24.0m / s86km / h
10000rpm30.0m / s108km / h

Next, let’s look at the average piston speed. The average piston speed at 6000 rpm, where an engine with a stroke of 90.0 mm produces maximum output, is 18.0 m / s , which is a piston speed that travels a distance of 18.0 meters per second (64.8 km / h at speed). It means that is moving up and down.

At 2750 rpm, which produces the maximum torque, 8.2 m / s, and when 6500 rpm, which is 500 rpm higher than 6000 rpm, which produces the maximum output, is assumed to be the rev limit, the average speed is 19.5 m / s.

For reference, I calculated the change in piston speed when a 6G75 engine with a stroke of 90.0 mm is rotated up to 10000 rpm. Looking at this, it seems that the speed increases by approximately 6.00 m / s as the number of revolutions increases by 2000 revolutions.

Considering only 20.0 m / s, which is a guideline for general engines assuming mass production, it is mechanical to set the upper limit of high rpm to about 6670 rpm (whether it rotates or not). It seems to be preferred both mentally.

Oil for 6G75

The filling volume of the 6G75 crankcase for oil is 4.9 liters. Shell Helix Ultra A5/B5 is best suited. There are many useful additives in this lubricant. Mobil Super 2000, Liqui Moly, Ravinol and others oils have proven themselves well.

There are as many recommendations for oil for 6G75 as there are opinions. Let’s start with the fact that this engine is considered structurally old, and this is more a plus than a minus. In other words, the engine is not as sensitive to oil viscosity as the latest internal combustion engines. Therefore, 6G75 is not very demanding in terms of fuel and oil. So, here’s what we managed to scoop out from the reviews of the owners.

  1. In winter, it is advisable to pour 0W-30 into the engine, and in summer – 5W-30. Some pour even 0W-20 or 5W-20. However, what should never be used is filling 6G75 with W-40 lubricant, as this composition is too viscous and can cause unnecessary trouble for owners.
  2. Residents of the capital and the central / northern strip can be limited to 0W-30 oil for the whole year. Owners of the 6G75, who live in southern latitudes, where it is hot in summer, will already have to change the lubricant, depending on the time of year.
  3. Some are of the opinion that for Moscow it is possible to pour 5W-30 all year round, but with frequent replacements. This will allow you not to overpay for zeroing, and why does the archaic (in terms of design) 6G75 need such a viscosity.
  4. There is another opinion that the zero base is stronger, and in winter such a viscosity is more comfortable for the capital, if there is no habit, warm up the engine. Yes, and the difference in price between these oils is insignificant, what kind of savings is there, one asks.
  5. Any oil that meets the manufacturer’s instructions can be poured into 6G75. According to ACEA A3 / B3 / B4, but not A5 / B5, although this is also possible for the sake of reducing fuel consumption and improving environmental performance, without regard to the resource of the engine. By viscosity SAE 0W-30, 5W-30 and even 5W-40, if only the lubricant was not a fake!
  6. For all Japanese and American engines, low viscosity oils are traditionally characteristic, have been used for a long time, and without problems. So, all American classics of the 50s and 60s were fed with W-20 W-30. Such oils do not have a lack of ash content, but it is recommended to change the lubricant, taking into account our conditions, at least once every 5 thousand kilometers.
  7. It is believed that the quality and parameters of the oils will depend on the 6G versions. For Mivec, for example, 504/507 are well suited.
  8. Full ash content is an excellent oil quality, achieved by cutting down on the package of antiwear and detergent additives. It is not worth judging the oil resource as a linear process – even with a change every 5 thousand km, a full-ash lubricant with high TBN / ZDDP is preferable. But low-ash oils were invented in order to allow a lubricant consumption of 1 l / 1000 as a norm. All Asian lubricants are considered low-ash.
  9. For an SUV weighing more than 2 tons, combining movement in urban traffic jams with a start / stop and off-road mode, it is preferable to fill in 0W-30 during winter operation, but in summer – 5W30 / 10W-30. As for the low-ash ones, they are not contraindicated for V6 engines, since frequent replacements cannot be avoided, due to operating conditions. For this reason, it makes no sense to fill in full-ash, because when changing the lubricant up to 200 hours, there will be no harm from the ash content of the lubricant.

What does viscosity really mean?

Oil viscosity is the most controversial parameter when choosing an oil. There are many points of view. They differ from sellers, dealers, mechanics, and finally, the car owners themselves. Often opinions contradict one another.

In fact, the most common misconceptions of motorists regarding the viscosity of engine oil are imposed by the manufacturers themselves. For example, this topic: for fans of fast driving, standard oil is not suitable – you need to fill in a special type of lubricant, sports. Of course, this is not the case – a real loss of power and an early overhaul in this case are provided.

The main task of normal engine oil is to prevent dry friction of the internal elements of the internal combustion engine, to ensure almost zero friction force with complete tightness of the cylinders. In non-static conditions, when the operating temperature range of the lubricant in the engine is wide enough, it is extremely difficult to make a universal substance. Oil can be 150 °, and 130 °, and 90 °. It all depends on the speed of movement, intensity, workload of the car.

Viscosity allows the oil to remain on the surface of the engine’s internals and remain fluid regardless of temperature. However, viscosity parameters are different, and the worldwide association of engineers SAE has developed a special classification representing the viscosity of a particular composition at different temperatures. In fact, it is a parameter of the temperature range that allows the use of oil.

In translation, 5W-30 (it is oil with this indicator that is often mentioned in reviews) means a multigrade oil that does not lose its original properties at low temperatures. In other words, a cold start of 6G75 with such a composition is possible at temperatures not lower than -35 ° C. As the degrees decrease, which is typical of the climate of the northern latitudes of our country in winter, 5W-30 oil will begin to thicken and lose its useful properties. It will become more and more difficult to start the engine.

The first digit of the SAE index means the minimum allowable use temperature, if you subtract 40 from it. 5 – 40 will be -35 ° C. The second digit in the designation already shows the maximum allowable degree of application. In this case, it is 30°C.

What is the ash content of oil?

Much has also been said about ash content. In fact, we are talking about the sulfate ash content of engine oil. Some praise the quality of low-ash oil, while others – on the contrary, full-ash. So what’s the difference?

Any of the oils is the main base and a set of unique additives that give the lubricant various properties. In the process of combustion of the composition, ash with solid non-combustible particles is formed. Their accumulation leads to clogging of filters and catalysts – they are no longer able to cope with their functions.

Sulfated ash is thus slag or an indicator of lubricant additives. With their help, during the combustion of oil, ash is formed, which is treated with sulfuric acid to prevent oxidative processes and the formation of sulfates.

It turns out that the higher the ash content in the oil, the higher the useful properties in it. However, manufacturers are forced to strictly dose additives in their own products, since a change in the sulfate ash content in either direction will lead to a change in the flash point. A large amount of soot (ash) is a barrier to the normal functioning of the engine.

Mitsubishi 6G75 3.8l engines Problems

  1. High oil consumption. Given the age of the engine, most likely the problem is in the oil scraper rings and caps. You need to check, buy new rings and caps and carry out repairs.
  2. Engine knock. Often the problem is associated with hydraulic lifters. Buy new hydraulic lifters, remove the valve cover and change. Sometimes 6G75 knock problems are caused by cranking of the connecting rod bearings. In this case, it is likely to get into an engine overhaul. Check and keep an eye on the oil level.
  3. The revolutions of XX are floating. Check the idle speed regulator, most often the problem is in it. Then inspect the condition of the throttle body, it may need cleaning.

In addition, every 100,000km it is necessary to replace the candles with 6G75. This procedure is difficult due to the need to remove the intake manifold. Along with this, it is necessary to inspect the intake manifold flange, grinding may be necessary.

To protect yourself from possible problems as much as possible, oil for 6G75 should only be of high quality. Do not save on gasoline, regularly undergo maintenance and your engine will run for a long time and without problems. The resource of the 6G75 engine is on average 400 thousand km or more, with normal maintenance.

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