E320cdi V6 or striaght 6

[harry hambi]

Hi Guys,
This thread has probably been covered before, pls excuse for repeating.
I have just driven a straight6 & and V6.....they drive like different cars.
The V6 seemed smoother & quicker.....the straight6 was very nice too, Just wondering what you experience Merc. owners had to say on the pros & cons of both cars. I would like to purchase an E320 cdi V6 or straight6 soon.
All comments appreciated.

 

[harry hambi]

Thanx Malcolm......what do you mean by, it can get through bottom CATs

 

[television]

Please ignore my CAT answers as does not apply to the diesel versions and get the V6 much better

 

[jberks]

if you can get a V6, do. As you say, totally different motors. The v6 is quieter, smoother and 24bhp more powerful as well as being a fair bit more economical. It doesn't feel it but it's actually over 1 sec faster to 60. It also has the 7 speed gearbox whereas the in line is a 5 speed.
Basically the IL6 is a second generation engine - where the CDIs really came of age. Great, but the V6 is a 3rd generation engine.
To drive, the difference is that all the il6's power comes in one short turbo powered blob. Great whilst 'on' but once you go beyond that, there's nothing. The V6 is much more linear in it's delivery so you have less drama but more overall power.
The turbo kick is great but I did once find myself joining a motorway on boost, shot out in front of the traffic with a great surge of power, expecting to tear away into the distance long before they got near me, only to drop off the power curve and find myself sitting there at 60mph, not accelerating, with traffic bearing down on me, waiting for the revs to build up again- not funny.

 

[Cole@MBS]

The v6 642 engine is starting to show its faults now, front main bearing knocking, import shut of motors seizing, crank sensors failing, teeth wearing off the balance shaft needing major strip down, started out well but showing its faults now.

 

[malcolm E53 AMG]

Hi Harry,
I can't comment on the V6 but can give you my thoughts based on experience of the IL6.

The IL6 is well respected by those that know, the motor trade, so speaks volumes. To my knowledge there are no known serious issues and the engine is renowned for being very strong.

My experience so far would endorse this. Problems to date @63K include:

1 x Glow plug failure
2 x injector failure (I had all six reconditioned, Bosch at fault)
1 x Serpentine belt and tensioner

There are people posting on this site who are running the V6 so I would take their comments on board to make a fair judgement. But my advice would be don't be frighened off an IL6 version. The only difference I would be particularly interested in is how the shorter and lighter block V6 affects the balance of the car. I would assume there might be a slight handling benefit.

A word of caution, beware Avantgarde suspension with 18in wheels, the 16in are OK and I would try the 17in before buying.

A fine car regardless of which engine you go for, get the best spec you can.

 

[harry hambi]

Hi Malcolm,
Great stuff, very helpful......come on you V6 owners tell me your thoughts, all comments appreciated.

 

[jberks]

Interesting point from SamUnit - the V6 is still fairly new so any design faults will only just be creeping through now.
I still contend that the V6 is a vastly better engine from a driver's perspective, but for 'bullet proof' reliability, yes the end of run IL6's will be hard to beat and still an all time great engine.

 

[Uncle Benz]

The v6 642 engine is starting to show its faults now, front main bearing knocking, import shut of motors seizing, crank sensors failing, teeth wearing off the balance shaft needing major strip down, started out well but showing its faults now.

Any idea of what sort of mileage the heavy metal faults start appearing?? The bearing shells have been very low demand from parts dept, so I am told... Are MB changing engines to rectify this??

 

[Cole@MBS]

As low as 20000 miles uncle, no not replacing engines,replacing the shells!!

 

[silverhorse]

The IL 6 engine is classed as bombproof by my Indie and he recommends a low mileage car if going for the V6.

 

[popuptoaster]

In theorry an inline 6 should be smoother than a V6 as its naturally balanced.

 

[hawk20]

I had the S320cdi with the straight 6 engine (Dec 2005) and I thought it was fabulous. Tremendous grunt. The 0-62mph time with the 5 speed box was almost exactly the same as the new S class with the V6 and 7 speed box. Then I had the use of the new model for about two months and 3-4,000 miles.

Impressions: - the new V6 is incredibly quiet and smooth. But far less impression of acceleration than the straight six (although the figs are almost identical). I felt the 7 speed box was totally unnecessary with so much power and especially torque. Some fairly clunky changes with the 7 speed too, but they keep updating the software and may be cured by now.

BTW fuel economy figures are virtually identical as well on the old and new S320cdi's.

I liked both. The V6 for how quiet it is at rest -even with the bonnet open you cannot believe it is a diesel. The straight six was more fun to drive. Put your foot down and the shove in the back was awesome. With the new engine and so many gears the new one is quick but smooth and less exhilarating.

Loved both.

 

[st4]

In theorry an inline 6 should be smoother than a V6 as its naturally balanced.

Exactly. With modern diesel tech advancements would the natural balancing effect be counteracted with more tech in the V6. V6's are smooth enough engines

The I6 was also EU3 compliant, the V6 EU4 complaint. There are some I6's with E4 compliancy. In peoples experiences on this forum and the "other one" the I6 is deemed to be much more economical than the V6. The I6 is definately proven and there are 210 E classes with >300k miles on them, the V6 is still relatively new and some recall work is coming through.

I've heard both engines on tickover, the V6 just pinks, it is unbelieveable quite and smooth on idle, much more so than the I6 CDi and BMW diesels. However I doubt the I6 will be corse enough to deter the OP.

There are pro's and cons with the 5speed box vs. 7 speed box. IMHO 7 forward gears are too many, and 5 is ample. There is nowt wrong with the 5 speed box so long as a valeo radiator isn't present. However with the I6 CDi car comes the age issue, which brings the valeo issue which simply isn't there on the V6 cars. When was the 211 facelifted, as facelifted CD's are V6 only, and have a range of cosmetic enhacements but the loss of SBC (one of the reasons to have a 211).

Personally I'd go for as new as possible I6 car as I could, preferrably a 2005 one - it will be cheaper than the newer V6 car.

 

[Simon Barry]

Any idea of what sort of mileage the heavy metal faults start appearing?? The bearing shells have been very low demand from parts dept, so I am told... Are MB changing engines to rectify this??

I am considering a 2005 -2007 E320 CDI and was somewhat concerned to read about
the faults in the V6 engine.

Are these faults still prevalent ?

Having driven a 2007 V6 320 CDI, I was quite taken with the car and was utterly amazed
how quiet it was on tickover.

I note that V6 are EU4 compliant, does that mean they all have that awful DPF ?

Simon Barry

 

[coolhans]

I have a 280 CDI V6. It's the same as the 320 CDI, that is 3 litres but a slightly lower state of tune. To be honest I've always been a fan of straight six engines and I also have a W124 E320 which is straight six and is as smooth as silk. The 280 is the first V6 I've ever had. I've had it for about eighteen months and done about 13000 miles in it and I have to admit I have found it astounding. It's right what others say, it's very powerful but the power is delivered in such a fuss free way. I liken it to being towed along by a giant elastic band. Very quiet and just gets on with the job. You could be fooled into believing it was a petrol. I like the 7G box although not every one does, some people complain of harsh changes but I have not found this except once or twice when trickling in traffic and it drops down to a low gear a bit abruptly. This has only happened three or four times since I've had the car. I can't comment on reliability apart from mine is fine but it has only done 64,000 which is baby mileage for a Merc. One thing I did notice was when in Germany last year I got a message telling me to check oil level next time I filled up. I checked it straight away and put half a litre in. So mine can use a bit of oil but my Indy said that this was normal.

 

[Simon Barry]

I have a 280 CDI V6. It's the same as the 320 CDI, that is 3 litres but a slightly lower state of tune. To be honest I've always been a fan of straight six engines and I also have a W124 E320 which is straight six and is as smooth as silk. The 280 is the first V6 I've ever had. I've had it for about eighteen months and done about 13000 miles in it and I have to admit I have found it astounding. It's right what others say, it's very powerful but the power is delivered in such a fuss free way. I liken it to being towed along by a giant elastic band. Very quiet and just gets on with the job. You could be fooled into believing it was a petrol. I like the 7G box although not every one does, some people complain of harsh changes but I have not found this except once or twice when trickling in traffic and it drops down to a low gear a bit abruptly. This has only happened three or four times since I've had the car. I can't comment on reliability apart from mine is fine but it has only done 64,000 which is baby mileage for a Merc. One thing I did notice was when in Germany last year I got a message telling me to check oil level next time I filled up. I checked it straight away and put half a litre in. So mine can use a bit of oil but my Indy said that this was normal.

Thank you, that is interesting. I have learnt that the 7G gearbox suffered from irregularities
at first but that software updates overcame them.

I had not heard that the V6 suffered significant failures reported earlier in this thread & just
wondered if they had proved to be isolated by now.

The particulate filter (DPF) is another concern that I wish to avoid, there appear to be
disadvantages both in short journeys & MPG. Does your 280 have one? There appears to
be some disparity between 04-06 on some models.

Simon Barry

 

[coolhans]

To be honest I don't know if my car has a DPF, all I can say is that it is the pre facelift model if that helps.

Regarding the 7G box mine is fine apart from what I mentioned earlier which I think has been the occasional glitch but very rare.

I have not heard of any bad things with this engine but maybe there are isolated occasions where something has gone wrong. I would say that could happen to any engine.

 

[prm]

Thank you, that is interesting. I have learnt that the 7G gearbox suffered from irregularities
at first but that software updates overcame them.

I had not heard that the V6 suffered significant failures reported earlier in this thread & just
wondered if they had proved to be isolated by now.

The particulate filter (DPF) is another concern that I wish to avoid, there appear to be
disadvantages both in short journeys & MPG. Does your 280 have one? There appears to
be some disparity between 04-06 on some models.

Simon Barry

I've got the E280cdi engine, its a dream to drive, no probs at all. A lot didn't have the DPF, mine hasn't and its a 57 reg, check the tail pipes, if sooty it won't have it

 

[moosehead]

I had numerous software upgrades on my 7G gearbox before they got it stable (mostly clunky downchanges at low speed). The electro hydraulic control unit in the box failed at 45K miles. Luckily it was still in warranty other wise £1000 for the part I'm told + labour. Other members have reported a few of these failing at a similar mileage.

I'm not a diesel fan but I have driven an E320CDI on a couple of occasions and have been very impressed. If I was after a diesel I wouldn't rule out the 220CDI. Again I have driven the facelifted 220CDI with the upgraded engine and it seems to perform extremely well and run for ages on a tank of fuel compared to my V6 petrol. The 220 also has the well proven 5 speed box.