Diesel vs Petrol, running cost vs MPG
Discussion
A recent change of job means that I now do 200-250 miles/week or ~10k miles/year (70% motorway, 25% dual carriageway, 5% sub 30mph urban roads)
I've been wanting to get a nicer, more comfortable and slightly more interesting car for a while now with a budget of around 7-8k and had my sight set on a 2nd gen Lexus IS250.
With the mileage I do now, would it be wise to still get an N/A petrol with Japanese reliability or get something similar in power, but diesel like a 330d or C350 CDI and hopefully avoid big bills by getting one with FSH and hoping that my longer drives will keep the DPF and EGR issues away? Will reliability outweigh the extra tank of fuel per month with the petrol?
Note that the BMW and other German contenders would also cost a few hundred more to insure likely as I am under 25 years old.
I've been wanting to get a nicer, more comfortable and slightly more interesting car for a while now with a budget of around 7-8k and had my sight set on a 2nd gen Lexus IS250.
With the mileage I do now, would it be wise to still get an N/A petrol with Japanese reliability or get something similar in power, but diesel like a 330d or C350 CDI and hopefully avoid big bills by getting one with FSH and hoping that my longer drives will keep the DPF and EGR issues away? Will reliability outweigh the extra tank of fuel per month with the petrol?
Note that the BMW and other German contenders would also cost a few hundred more to insure likely as I am under 25 years old.
I’ve done it both ways!
We own an IS250 now and we love it. Also have an E350 cdi ticking off the diesel.
It really depends on what you like.
I was doing 20,000 miles per year and bought a GS300 for around £3000. It was excellent. Refined, all the comfort and toys you want, faultless reliability and would do over 40 mpg. Sold it for what I bought it for.
The Mercedes is a high spec W212 estate and great at what it does. Not ULEZ and probably worth about 5p now! Engine more gruff than the IS250 but obviously more powerful and with lots more torque. My previous BMW 535d was more refined.
If I really try, and I do mean trying, then I can get 40 mpg on the motorway (70 mph) but realistically mid 30s as an average.
My money would be on a comfortable, big petrol like a GS300 or IS250 or something like a Honda Legend.
Cheap, reliable, comfortable and essentially disposable after a few years.
We own an IS250 now and we love it. Also have an E350 cdi ticking off the diesel.
It really depends on what you like.
I was doing 20,000 miles per year and bought a GS300 for around £3000. It was excellent. Refined, all the comfort and toys you want, faultless reliability and would do over 40 mpg. Sold it for what I bought it for.
The Mercedes is a high spec W212 estate and great at what it does. Not ULEZ and probably worth about 5p now! Engine more gruff than the IS250 but obviously more powerful and with lots more torque. My previous BMW 535d was more refined.
If I really try, and I do mean trying, then I can get 40 mpg on the motorway (70 mph) but realistically mid 30s as an average.
My money would be on a comfortable, big petrol like a GS300 or IS250 or something like a Honda Legend.
Cheap, reliable, comfortable and essentially disposable after a few years.
Pesto217 said:
A recent change of job means that I now do 200-250 miles/week or ~10k miles/year (70% motorway, 25% dual carriageway, 5% sub 30mph urban roads)
I've been wanting to get a nicer, more comfortable and slightly more interesting car for a while now with a budget of around 7-8k and had my sight set on a 2nd gen Lexus IS250.
With the mileage I do now, would it be wise to still get an N/A petrol with Japanese reliability or get something similar in power, but diesel like a 330d or C350 CDI and hopefully avoid big bills by getting one with FSH and hoping that my longer drives will keep the DPF and EGR issues away? Will reliability outweigh the extra tank of fuel per month with the petrol?
Note that the BMW and other German contenders would also cost a few hundred more to insure likely as I am under 25 years old.
I'd suggest looking at the Infiniti range as they'll tick your boxes, they're reliable as well as being a nice place to be.I've been wanting to get a nicer, more comfortable and slightly more interesting car for a while now with a budget of around 7-8k and had my sight set on a 2nd gen Lexus IS250.
With the mileage I do now, would it be wise to still get an N/A petrol with Japanese reliability or get something similar in power, but diesel like a 330d or C350 CDI and hopefully avoid big bills by getting one with FSH and hoping that my longer drives will keep the DPF and EGR issues away? Will reliability outweigh the extra tank of fuel per month with the petrol?
Note that the BMW and other German contenders would also cost a few hundred more to insure likely as I am under 25 years old.
M30d, these have the nice bonus of being ULEZ compliant & you can add Android Auto/Carplay for around £500:
https://www.autotrader.co.uk/car-details/202402196...
Q70:
https://www.autotrader.co.uk/car-details/202408162...
Q50 2.0T:
https://www.autotrader.co.uk/car-details/202407282...
2.1d:
https://www.autotrader.co.uk/car-details/202405159...
https://www.autotrader.co.uk/car-details/202406070...
This is a bit of an age old question.
This is just my opinion, but diesels are excellent if you're going to finance or lease one for the first 3 years of the car's life.
But my experience with older diesels is that the maintenance has engulfed the money saved on fuel.
With turbos, EGR valves, coked engines, injectors and DPFs I found there was way more to go wrong than a simple N/A car.
So you need to be doing at least 20,000 miles per year to see the benefits of a diesel, plus there's the question of whether you're willing to pay a bit more per year in fuel to drive a petrol car.
This is just my opinion, but diesels are excellent if you're going to finance or lease one for the first 3 years of the car's life.
But my experience with older diesels is that the maintenance has engulfed the money saved on fuel.
With turbos, EGR valves, coked engines, injectors and DPFs I found there was way more to go wrong than a simple N/A car.
So you need to be doing at least 20,000 miles per year to see the benefits of a diesel, plus there's the question of whether you're willing to pay a bit more per year in fuel to drive a petrol car.
We might just be lucky but my wife has had a 330d BMW convertible (E93) for nearly 2 years now, goes 5 miles to work and back every day, I occasionally take it on a run down the motorway but we have had no issues at all.
Previous to this she had a brand new Peugeot 2008 with the 1.2 petrol and it was worse on fuel with the same driving profile, didn't clock mpg but how much she Is actually spending.
Don't always discount a diesel
Previous to this she had a brand new Peugeot 2008 with the 1.2 petrol and it was worse on fuel with the same driving profile, didn't clock mpg but how much she Is actually spending.
Don't always discount a diesel
jonwm said:
We might just be lucky but my wife has had a 330d BMW convertible (E93) for nearly 2 years now, goes 5 miles to work and back every day, I occasionally take it on a run down the motorway but we have had no issues at all.
Previous to this she had a brand new Peugeot 2008 with the 1.2 petrol and it was worse on fuel with the same driving profile, didn't clock mpg but how much she Is actually spending.
Don't always discount a diesel
My 335d BMW (8 years old) used to do long distances, but now does 20 mile round trips a few times a week, and a monthly longer trip. No issues. Previous to this she had a brand new Peugeot 2008 with the 1.2 petrol and it was worse on fuel with the same driving profile, didn't clock mpg but how much she Is actually spending.
Don't always discount a diesel
Also, diesel v petrol is not just about fuel savings, it’s more about the torque. I am personally hanging on until EVs mature a bit more and there is more variety to chose from.
AlexNJ89 said:
Maybe I've just been unlucky then.
How many miles do injectors usually need to be replaced? That was the costly thing for me, it was thousands.
EGR valve replacement was about £800 so not bad, but the valve getting stuck closed really coked up the engine.
160k miles on my Octavia vRS and not had an injector or EGR problem yet, despite quite a few years doing a lot of relatively short journeys.How many miles do injectors usually need to be replaced? That was the costly thing for me, it was thousands.
EGR valve replacement was about £800 so not bad, but the valve getting stuck closed really coked up the engine.
I've had diesels for the last 20+ years and like the relaxed way they drive on a longer journey, but I'd say the OP's mileage is pretty low to be considering diesel as cheaper to run, and as more and more low emissions zones come in I'd be concerned about both not being able to go to places, and the future resale value. Mine's a Euro4 and I believe I'd have to pay the ULEZ charge in London and possibly a few other UK cities, there are plenty of cities across Europe that an issue too, and these rules are only going to get tighter.
Get a 2007 LS460 - it used to get around 30mph on the motorway when new according to the forums.
It's got an awesome 4.6 V8, and it will make the IS250 feel like a toy car in comparison, and you can commute in complete luxury on the motorway.
They seem to be around 6 grand these days.
It's got an awesome 4.6 V8, and it will make the IS250 feel like a toy car in comparison, and you can commute in complete luxury on the motorway.
They seem to be around 6 grand these days.
raspy said:
Get a 2007 LS460 - it used to get around 30mph on the motorway when new according to the forums.
It's got an awesome 4.6 V8, and it will make the IS250 feel like a toy car in comparison, and you can commute in complete luxury on the motorway.
They seem to be around 6 grand these days.
Just sold mine and it was an excellent car with no issues at all.It's got an awesome 4.6 V8, and it will make the IS250 feel like a toy car in comparison, and you can commute in complete luxury on the motorway.
They seem to be around 6 grand these days.
And yes you can get that MPG on a run.
The more modern you go, the smaller the gap gets between diesel and petrol. In the mid 2000's, you'd be looking at a much larger gap. A lot of petrol cars would be somewhere in the 30's, many diesel cars up in the 50's. Now, a fair few petrol cars are getting 50mpg without much trouble and diesels are approaching 60's. I think the simple petrol NA reliability is hard to beat. You might save £500 a year on fuel in a diesel but 1 DPF failure and you're all of a sudden 4 times that in the red by the time it's broken, recovered, in a garage, parts sourced, fitted, programmed, and you've had to rent something for a week. The most reliable engines I've had have all been NA. Less to go wrong and the emissions guff on a diesel is extensive, expensive and much harder worked due to the carbon build up so prevalent on diesels.
RazerSauber said:
The more modern you go, the smaller the gap gets between diesel and petrol. In the mid 2000's, you'd be looking at a much larger gap. A lot of petrol cars would be somewhere in the 30's, many diesel cars up in the 50's. Now, a fair few petrol cars are getting 50mpg without much trouble and diesels are approaching 60's. I think the simple petrol NA reliability is hard to beat. You might save £500 a year on fuel in a diesel but 1 DPF failure and you're all of a sudden 4 times that in the red by the time it's broken, recovered, in a garage, parts sourced, fitted, programmed, and you've had to rent something for a week. The most reliable engines I've had have all been NA. Less to go wrong and the emissions guff on a diesel is extensive, expensive and much harder worked due to the carbon build up so prevalent on diesels.
This is what I've found to. It's as if the forced induction puts additional stress on the engines.Diesel still works out if you're doing big miles.
I think it's also worth exploring depreciation too, it appears that the petrol variant of each car tends to hold it's money better.
eth2190 said:
Lexus GS450h to have your cake and eat it. 38mpg on a run, 350hp, low 5 second 0-60.
I have the 2012 Mk3 450h , mine shows 35-6 mpg, mainly very short town work & 2 trips a week over 40 miles each way so pretty good. its more comfortable than my older E55 AMG S/Charged , not as quick but only 6 tenths or so from rest to 60 (5.2) & Tbh, on the move from (15 -25-40mph) there is nothing in it apart from E55 best was 26mpg to 9mpg...
regarding diesels & DPF clogging, I found the system on the Ford 2.0TDCi was very good as it has an extra injector just before the DPF & kept things clean, although if there was a problem it would generally be the injector or feed pipe to injector clogged ,so an easier fix plus 50+mpg estate with bags of space but no real go etc.
Edited by Gerradi on Tuesday 27th August 18:03
Pesto217 said:
A recent change of job means that I now do 200-250 miles/week or ~10k miles/year (70% motorway, 25% dual carriageway, 5% sub 30mph urban roads)
I've been wanting to get a nicer, more comfortable and slightly more interesting car for a while now with a budget of around 7-8k and had my sight set on a 2nd gen Lexus IS250.
With the mileage I do now, would it be wise to still get an N/A petrol with Japanese reliability or get something similar in power, but diesel like a 330d or C350 CDI and hopefully avoid big bills by getting one with FSH and hoping that my longer drives will keep the DPF and EGR issues away? Will reliability outweigh the extra tank of fuel per month with the petrol?
Note that the BMW and other German contenders would also cost a few hundred more to insure likely as I am under 25 years old.
Is that work mileage only , I do 300/ 360 miles to work & back , I’m going to be 20 k + and that’s with using my wife’s car when I’m not at work most of the time .I've been wanting to get a nicer, more comfortable and slightly more interesting car for a while now with a budget of around 7-8k and had my sight set on a 2nd gen Lexus IS250.
With the mileage I do now, would it be wise to still get an N/A petrol with Japanese reliability or get something similar in power, but diesel like a 330d or C350 CDI and hopefully avoid big bills by getting one with FSH and hoping that my longer drives will keep the DPF and EGR issues away? Will reliability outweigh the extra tank of fuel per month with the petrol?
Note that the BMW and other German contenders would also cost a few hundred more to insure likely as I am under 25 years old.
It’s not just the fuel costs , it’s tyres , wore front 2 out in under a year , needed a service after 7/8 months , it’s also the loss in value with the extra miles on the car , I was 46,000 just under a year ago , I’m now 67,000.
It’s a risk buying a cheap car , but I wish I’d paid 2/3 k for a cheap diesel to be honest .
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