6 cylinder diesel ~ 20-25k

[wong]

Which is the most reliable 6 cylinder diesel? Will be looking to keep it for 10 years if nothing major goes wrong. Anything from 2013-2017, 20-25K. Prefer estate/touring.
First looked at 5/330d. Whilst the 5/335d is faster, esp. more torque, is it any less reliable?
How do the Mercedes E/C class 6 cylinders compare for reliability?

Also views on xDrive.

[morebeanz]

Audi A6 Avant 3.0tdi would be my view.

I have a 2008 model year (owned since 2009) with 147,000 on the clock that has been faultless through its entire life, and goes like a train. Masses of space and has taken the abuse of a growing family in its stride. Mine has sports suspension which does its job, but can be uncomfortable on bad roads.

[robbieduncan]

Not sure past performance really translates to current, especially as models change and this impacts reliability. However I have a 12 year old 525d touring. It’s a E61 LCI model from about a 6 month period where this was a 6 cylinder 3.0 engine without DPF or swirl flaps. I spent a while looking into failures and chose this specifically as two of the major issue-causing items were not fitted to this engine. Now on 102k miles and still going strong with standard servicing only.

[SD_1]

morebeanz said:

Audi A6 Avant 3.0tdi would be my view.

I have a 2008 model year (owned since 2009) with 147,000 on the clock that has been faultless through its entire life, and goes like a train. Masses of space and has taken the abuse of a growing family in its stride. Mine has sports suspension which does its job, but can be uncomfortable on bad roads.

I'll second that, I have an 2008 B7 A4 Avant with that engine on 136k and it is an extremely good car. Pulls very well indeed and the fuel economy is very impressive too, although mine is a manual.

If you get a check engine light, it is probably the inlet manifold swirl flap motor going. Audi used to charge a fortune to replace the entire manifold, but you can get a repair kit for them which is what I did to mine and was not expensive. Aside from that, it has only had routine maintenance since new and still feels as strong as day 1. Interior looks new, very impressed with how it has worn its years.

[daveco]

robbieduncan said:

Not sure past performance really translates to current, especially as models change and this impacts reliability. However I have a 12 year old 525d touring. It’s a E61 LCI model from about a 6 month period where this was a 6 cylinder 3.0 engine without DPF or swirl flaps. I spent a while looking into failures and chose this specifically as two of the major issue-causing items were not fitted to this engine. Now on 102k miles and still going strong with standard servicing only.

I went with the 525d in the F10, the earlier 3.0 litre version with 201hp. The engine is superb and faultless for the last 25,000 miles of driving. Regularly get over 600 miles out of a tank too. Has a nice uncharacteristic burble to it, not diesel like at all. The 8 speed auto box works very well with it.

530d is supposed to be just as reliable but heard the fuel economy is far worse. The 535d has its issues so try to get one with BMW's 2 year warranty and low mileage, so you can extend the warranty yourself if you plan to own it for more than two years.

Edited by daveco on Thursday 4th April 08:14

[robbieduncan]

daveco said:

I went with the 525d in the F10, the earlier 3.0 litre version with 201hp. The engine is superb and faultless for the last 25,000 miles of driving. Regularly get over 600 miles out of a tank too. Has a nice uncharacteristic burble to it, not diesel like at all. The 8 speed auto box works very well with it.

530d is supposed to be just as reliable but heard the fuel economy is far worse. The 535d has its issues so try to get one with BMW's 2 year warranty and low mileage, so you can extend the warranty yourself if you plan to own it for more than two years.

Edited by daveco on Thursday 4th April 08:14

I believe this is the slightly updated version of the same engine but with a DPF and swirl flaps. I think, but am not 100% sure, that the swirl flaps will be the updated versions rather than the earlier all-plastic fail-prone ones but worth checking. DPF should be fine as long as you treat it right (like any other DPF). I agree on the sound. It’s much nicer than you expect from a diesel

[Big GT]

The Jag XF S would get my vote. Lovely smooth V6 and the XF is the best car in class. We've ran a number of these engines to well over 200K in Disco 4's and no major problems.

a second for the Audi 3.0tdi , smooth and our fleet have had 2 A4's, 3 A6's and an A8 with this engine all covering 100K miles with no problems.
Touareg 3.0tdi is a lovely drive.

I've run a number of BMW 3.0tdi and again only one problem due to ECU.

No Merc experience

[Jimi.K.]

When I was researching this last year the Audi 3.0tdi kept coming up as a reliable option. I bought a 2010 A5 sportback with that engine and I've taken it from 147k to 155k miles so far with no issues and it feels like it will do 250k+ miles with ease.

[ZX10R NIN]

For me it would be Jaguar XF then the CLS350/E350 & finally the Audi & BMW vying for third.

[AllyBassman]

My vote would be for a Mercedes E350 or C350 if you don't need a Cathedral sized boot.

The OM642 is a lovely V6 Diesel, more reliable than the BMW straight 6, Ooozles of torque and sounds pretty decent for a Derv.

[Summit_Detailing]

I've owned 3.0 diesels from BMW, Audi and Mercedes, all very similar in terms of performance, the engine/gearbox combo in the Audi wasn't quite as refined and in-tune with each other compared to the BMW and Mercedes alternatives.

As an above poster has mentioned and any research you do will show the Mercedes V6 to be the most reliable out of the three.

I've just gone from BMW diesel to Mercedes V6 a couple of weeks ago funnily enough, absolutely no regrets.

Enjoy the hunt!

cheers,

Chris

[ninjag]

Jaguar XF Sportbrake also gets my vote and not as common either. Very underrated oh my opinion.

Portfolio gets the upgraded Meridian system as standard but you can find other derivatives which have had it spec'd from new. The easiest tell-tale is the door speakers will have Meridian Surround badges rather than just Meridian.

I drove an F11 530d XDrive and whilst it was nice enough with lots of grip (although rather floaty feeling) I didn't feel very engaged and the handling felt like I was relying on the car rather than being able to feel the road for myself. I also kept coming across people who had rear air suspension problems which put me off.

[Shiv_P]

ninjag said:

Jaguar XF Sportbrake also gets my vote and not as common either. Very underrated oh my opinion.

Portfolio gets the upgraded Meridian system as standard but you can find other derivatives which have had it spec'd from new. The easiest tell-tale is the door speakers will have Meridian Surround badges rather than just Meridian.

I drove an F11 530d XDrive and whilst it was nice enough with lots of grip (although rather floaty feeling) I didn't feel very engaged and the handling felt like I was relying on the car rather than being able to feel the road for myself. I also kept coming across people who had rear air suspension problems which put me off.

I don't think 530d F10/F11 xdrive were available in UK

[Hammerhead]

Another vote for the XF Sportbrake. The 3.0D is a very nice unit and is plenty quick enough when you prod it. Plus the Sportbrake is very decently sized if you have to carry lots of stuff. Swallows MTBs with wheels still on, no problem!

[ninjag]

Shiv_P said:

I don't think 530d F10/F11 xdrive were available in UK

I'm sure the one I drove was but could be wrong. My 330d was xdrive and it felt floaty.

Update, I think it was the new one. It was a 2017 plate whichever one that is.

Edited by ninjag on Friday 5th April 17:33

[wong]

Thanks for all the input.
I hadn't really considered Audi or Jaguar before.More homework needed.

[ZX10R NIN]

XF S Portfolio

https://www.autotrader.co.uk/classified/advert/201...

https://www.autotrader.co.uk/classified/advert/201...

CLS 350 Premium Plus AMG Line

https://www.autotrader.co.uk/classified/advert/201...

https://www.autotrader.co.uk/classified/advert/201...

E350 Premium AMG Line

https://www.autotrader.co.uk/classified/advert/201...

Night Edition Premium

https://www.autotrader.co.uk/classified/advert/201...

A6 S Line

https://www.autotrader.co.uk/classified/advert/201...

https://www.autotrader.co.uk/classified/advert/201...

Black Edition

https://www.autotrader.co.uk/classified/advert/201...

https://www.autotrader.co.uk/classified/advert/201...

535d M Sport

https://www.autotrader.co.uk/classified/advert/201...

https://www.autotrader.co.uk/classified/advert/201...

530d

https://www.autotrader.co.uk/classified/advert/201...

[si_xsi]

Another vote for XF S portfolio, in fact I pick mine up tomorrow, readers car thread to follow. I looked at A6 3.0tdi but found them to be too clinical for my tastes The jaguar is a step above In my opinion in terms of style and standard equipment, especially in portfolio trim.

Edited by si_xsi on Saturday 6th April 06:52

[cerb4.5lee]

In terms of engine I much preferred the twin turbo 3 litre diesel I had in my 640d to the V6 3 litre single turbo diesel engine I have now in a GLC 350d.

There isn't much between the weight of the two cars but the 35d/40d engine feels much more punchy than the Mercedes V6 unit to me.

[irish boy]

Impressive how long this thread has gone without someone telling you that diesel is the wrong choice.

Had a drive in a 335d last year and loved it. Not 6 cylinder but check out the bitdi passat 240 hp. Absolutely superb engine/gearbox combo, reliable, quick and my neighbours one is averaging 46.