The Lemon Fool

For 38 years I have only ever owned and driven petrol cars - Cortina, Escort (x2), Rover Coupe, Alfa 156,Volvo V70 and Mercedes C class. I have never had any desire to have a diesel car, not because I ever did any exhaustive thinking about it, I just didn't see the need, even when we were "nudged" to with cheaper fuel and lower car tax. I also don't have any desire now for a hybrid or electric car, although that may very well change soon.

Now Mrs C and I really want to get a used Mercedes GLC (well, I actually want a Maserati Levante, but even I can see the slight impracticalities of that, living as we do in a terraced house in North London with no garage or OSP), but they are only available with diesel engines.

Would now be a really stupid time to change my habit and buy a diesel?

In your answers you should assume (because it's true) that I know next to nothing about cars except whether they look nice.

I don't know how big a Mercedes GLC is, but with Range Rovers and the like, diesel is the only vaguely economic way of running one.

A petrol version is likely to get single figure mpg in the real world.

Scott.

You say you live in North London: I'd look at whereabouts you intend to drive and see if there's a current penalty for high emissions (or an outright ban on bringing the car in).

It's not so much that the GLC is a "dirty diesel" but that areas that led the introduction of air pollution control are likely to continue to lead, which at some point will probably ban or otherwise penalise your car. Depending on how long you plan to keep it, this may or may not be of concern.

The sale of new pure diesels aren't due to be banned until 2040, so I don't see a problem with access to fuel or even resale value for the next decade or so.

One thing that you might want to consider is your typical journey. Diesels are designed for longer journeys and use EGR (exhaust gas recirculation) to improve fuel economy. This soots up when the engine is not up to temperature and is cleaned when full temperatures are reached, sometimes with a cleaning cycle that diverts some power from the engine. If you make mainly short journeys, a diesel will give you nothing like the brochure performance and will run frequent EGR cleaning cycles that further degrade performance.

You m\y also want to check if the particular model you want has been affected by "dieselgate". Whilst synonymous with VW, Mercedes have also been recalling cars to make engine modifications.

Assuming none of the above is an issue in your case, if the car is what you want then I'd ignore the fuel type (except when refueling...) and enjoy driving it!

VRD

Shurely, GLC = Greater London Council?

So (as above, thanks VRD) give them a ring and ask how much they'll charge you to drive it into the congestion zone? (Now and in about four years' time.)

If that's not a big issue for you, you don't really have a problem. Unless you count the staggering complexity of your average modern diesel engine, of course. And unless the local Greenpeace office is just up the road. Try not to buy one of the very first models with the engine that you decide on, and you should be OK.

BJ

I don't know how big a Mercedes GLC is, but with Range Rovers and the like, diesel is the only vaguely economic way of running one.

Not much bigger than my current C Class.

I'd look at whereabouts you intend to drive and see if there's a current penalty for high emissions (or an outright ban on bringing the car in).

Yes, that's one thing that had occurred to me, and whether there were going to be more of them in future.

If you make mainly short journeys, a diesel will give you nothing like the brochure performance and will run frequent EGR cleaning cycles that further degrade performance.

Mostly short journeys, almost daily ones of 4-5 miles, and maybe a couple of 100-150 milers per month.

Try not to buy one of the very first models with the engine that you decide on, and you should be OK.

Noted, I wouldn't have thought of that.

I think every other person in my street is a member of Greenpeace, so I'll just have to ignore that aspect! Actually, the GLC is quite compact really, not much bigger than an average saloon, not as noticeable as a Land Rover for instance. Only really looking at it as Mrs C, being vertically challenged, wants to be higher up.

Also looking at the Volvo XC60, which does have a petrol version. I don't understand why the GLC is diesel only. I'm thinking of going to the Mercedes dealer and asking for a petrol one, then going and buying the Volvo.

MrCake wrote:

I don't know how big a Mercedes GLC is, but with Range Rovers and the like, diesel is the only vaguely economic way of running one.

Not much bigger than my current C Class..

I am sure you've read the bad bits on:
https://www.honestjohn.co.uk/carbycar/m ... ction=good

Go for the Volvo imho

Re petrol vs diesel, how do you feel about the depreciation rate on your diesel being (say) double that on the petrol version. That might be the practical effect over the next five years.

Me - driving a 15-year old Golf mk IV diesel, fully depreciated.

regards, dspp

Thanks DSPP. Actually I didn't know that because we are just at the initial thinking about what might be a decent shortlist stage, haven't gone into the research phase yet. This has put me off the GLC a bit though.

Maybe the Maserati is the "sensible" choice after all!!!!

MrCake wrote:Maybe the Maserati is the "sensible" choice after all!!!!

They are £80k new, and lose 25% in the first year.

Depends on your definition of "sensible"!

Paul

MrCake wrote:.....Mostly short journeys, almost daily ones of 4-5 miles.....

A modern diesel car is not suitable for that kind of use.
There's a high risk of DPF problems which could result in the car spending several days a year at the dealers and maybe expensive repairs.

MrCake wrote:Mostly short journeys, almost daily ones of 4-5 miles, and maybe a couple of 100-150 milers per month.

That sounds like modern electric car territory.


Slarti

Slarti wrote:

MrCake wrote:Mostly short journeys, almost daily ones of 4-5 miles, and maybe a couple of 100-150 milers per month.

That sounds like modern electric car territory.


Slarti

A model S Tesla would look nice on the drive!

For 38 years I have only ever owned and driven petrol cars - Cortina, Escort (x2), Rover Coupe, Alfa 156,Volvo V70 and Mercedes C class. I have never had any desire to have a diesel car, not because I ever did any exhaustive thinking about it, I just didn't see the need, even when we were "nudged" to with cheaper fuel and lower car tax.

Replace 38 with 25, and petrol with diesel, then that describes me. Here in Italy, like most countries, diesel is a tiny bit cheaper than petrol but I'd stick with diesel even if it cost more.

I absolutely hate petrol cars. I didn't realise it until I'd been using a Passat diesel for years and then rented a petrol car. The petrol gauge seemed to be totally wonky and it went from 1/4 full to empty in less than an hour. Then I borrowed a petrol car in the UK and realised that this is normal. With a diesel I know that it will go for ever without me having to fill up whereas with petrol, I was always keeping an eye on the gauge. I don't handle stress too well and find that I'm a lot calmer in a diesel where I know it will go for ages without me worrying about the fuel.

Now I have a Volvo and it's so quiet, clean and seems less smelly than a petrol car. Hopefully it will last until we all go electric, nuclear or have to use bicycles.

PS If you don't like diesel fuel, you can always try filtered vegetable oil, which is what the engine was originally designed for.

Steve

stevensfo wrote:
I absolutely hate petrol cars. I didn't realise it until I'd been using a Passat diesel for years and then rented a petrol car. The petrol gauge seemed to be totally wonky and it went from 1/4 full to empty in less than an hour.

In many cars the fuel gauge is not linear. I've seen some cars with two gallons above the 'full' marker (i.e. the gauge doesn't move from full until two gallons have been used) then two gallons between each of the full/75%/50%/25% markers, and another gallon in reserve after the fuel gauge shows zero. For example:
Full = 9-11 gallons in tank (82-100% full)
3/4 = 7 gallons (66% full)
1/2 = 5 gallons (45% full)
1/4 = 3 gallons (27% full)
empty = 1 gallon (9% full)

.....With a diesel I know that it will go for ever without me having to fill up whereas with petrol, I was always keeping an eye on the gauge. I don't handle stress too well and find that I'm a lot calmer in a diesel where I know it will go for ages without me worrying about the fuel.

Diesel typically manages about one-third further on a tank. Say 40mpg vs 30mpg.
However, diesel is almost as thirsty as petrol when used for short journeys because typically diesel engines take longer to warm up to normal operating temperature where they are most efficient.

Some of the small petrol cars can be economical without being punished for NOx emissions and without the complexity of a modern diesel.
My recently-acquired second car is a Vauxhall Viva (2017 model) 1-litre petrol gives around 45mpg in rush hour, 55mpg on the motorway and 65mpg on long single-carriageway journeys. Those figures take into account the trip computer exaggeration which shows around 7% higher.
Road tax only £20 for cars like the above that were registered before April 2017.
I would expect equivalent cars from other manufacturers to show equally impressive mpg (e.g. VW Up, Seat Mii, Skoda Citigo, Suzuki Celerio, Kia Picanto, Citroen C1, Peugeot 108, Toyota Aygo).

....PS If you don't like diesel fuel, you can always try filtered vegetable oil, which is what the engine was originally designed for..

Unfortunately, high-tech modern diesel engines are usually too fussy to be able to cope with veg oil.

.

BT63 wrote:Unfortunately, high-tech modern diesel engines are usually too fussy to be able to cope with veg oil.

Wot he said. The problem with putting any veg oil into a modern common rail engine is not only that it'll clog up the injectors. More seriously, it'll wreck the high-pressure fuel pump, which is designed to run at something silly like 23 tonnes per square inch. And which is kinda fussy about the quality of the lubrication that it gets from the fuel as it pumps it along.

About £1,000 per time to replace the pump. Maybe not such a good idea? But I gather that you can still run trucks on chip fat.

BJ

bungeejumper wrote:I gather that you can still run trucks on chip fat.

BJ

Indeed. McDonalds make a feature of it in their environmental credentials advertising, whilst a whole new industry has blossomed around recycling chippie oil. Gone are the days when they'd pay you to dispose of it for them!

You can process chippie oil for your diesel, e.g. http://news.bbc.co.uk/1/hi/sci/tech/7047128.stm but probably better to drive an old diesel, not a modern engine!

VRD

bungeejumper wrote:
About £1,000 per time to replace the pump. Maybe not such a good idea? But I gather that you can still run trucks on chip fat.

BJ

But pretty simple to make Biodiesel if you are that way inclined.

RC