What is high mileage for a petrol + diesel when buying a car

What is high mileage for a petrol + diesel when buying a car

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Discussion

sixty

Original Poster:

91 posts

138 months

Tuesday 4th September 2012
quotequote all
I've had many people tell me not touch Petrol engines over 100k.

Where as diesels can have an urban myth like industrial solidness "oh it will easily get to 300k if serviced well" LOL

In your experience what is high mileage for a petrol and a diesel car when buying second hand? - Particularly from a risk/increased change of problems point of view.

HustleRussell

24,602 posts

159 months

Tuesday 4th September 2012
quotequote all
sixty said:
...Where as diesels can have an urban myth like industrial solidness "oh it will easily get to 300k if serviced well" LOL
It's no myth. 300k is a totally reasonable life expectancy for many of the better engineered engines of the last few decades.
The engine, whether it runs on petrol or diesel, is in all probability capable of 200,000 miles at the very least if it's serviced and maintained. It is the engine's ancillaries which let it down, and other faults with the car as a whole such as corrosion and failure of other expensive-to-fix parts.

What goes wrong with an engine?
-valvetrain damage- most often caused by cambelt failure (servicing will prevent)
-head gasket failure- usually an underlying cause such as overheating caused by thermostat failure, water pump failure or coolant leak (servicing will prevent)
-bearing wear- rarely becomes sufficient to write off an engine unless it has had too little/too much oil or has been overheating.
-detonation- pretty much a thing of the past with knock sensors and modern fuels.

Edited by HustleRussell on Tuesday 4th September 23:48

rallycross

12,747 posts

236 months

Tuesday 4th September 2012
quotequote all
A one owner 3 yr old petrol car that has done 150k motorway miles is just run in.

A one taxi owner 3 yr old diesel that has done 90k miles mini cabing in London will be worn out.

The friends who told you a 100k mile petrol will be worn out are either misinformed or stupid.

Matt UK

17,649 posts

199 months

Tuesday 4th September 2012
quotequote all
I've run both petrol and diesel engines well past 150k miles with no issues.

I've also had a petrol lunch itself at 60k miles and a diesel blow it's turbo to bits at 45k miles.

There are no real rules.

FreeLitres

6,039 posts

176 months

Tuesday 4th September 2012
quotequote all
Depends a lot on the car.

A newish 150k mile 5-series Beamer will probably be in better shape than a TVR on 150k miles on it's first engine.

DukeDickson

4,721 posts

212 months

Wednesday 5th September 2012
quotequote all
sixty said:
I've had many people tell me not touch Petrol engines over 100k.

Where as diesels can have an urban myth like industrial solidness "oh it will easily get to 300k if serviced well" LOL

In your experience what is high mileage for a petrol and a diesel car when buying second hand? - Particularly from a risk/increased change of problems point of view.
There's plenty of experience on here about petrol engines with significantly greater miles and few/no issues.

I had a boggo Astra with @ double that silly limit. Only issues were a water pump and the electronic choke - old Astra smile. It was still on it's original clutch as well. It died, but not as a result of engine death - insurance w/off.
I now have a Focus on 113k. It hasn't had a cambelt change yet, still hasn't had one drop of oil outside of a service and has had one slight flutter that was some minor cooling system thing & cost 40 quid to fix. If other bits weren't a bit tired, I didn't want a change and would be prepared to do the multi car thing (not just at the moment), it would be good for the same again.


The right petrol car with the right past will be no issue @ 100k.

Edited by DukeDickson on Wednesday 5th September 00:04

jbi

12,668 posts

203 months

Wednesday 5th September 2012
quotequote all
lets take the volvo 2.5 and jeep 4.0 I am currently driving. (both petrol)

At the moment both are around 100k miles and "just run in" IMO

I fully expect them to last well beyond 200k with regular oil changes.

As for modern diesels... wouldn't touch them with a barge pole. Too much emissions related crap, expensive injectors and fuel pumps and very costly when they do go wrong.

shorts!

683 posts

253 months

Wednesday 5th September 2012
quotequote all
FreeLitres said:
Depends a lot on the car.

A newish 150k mile 5-series Beamer will probably be in better shape than a TVR on 150k miles on it's first engine.
Traitor!

FloppyRaccoon

1,916 posts

165 months

Wednesday 5th September 2012
quotequote all
Matt UK said:
I've run both petrol and diesel engines well past 150k miles with no issues.

I've also had a petrol lunch itself at 60k miles and a diesel blow it's turbo to bits at 45k miles.

There are no real rules.
Agree with this.

Captain Cadillac

2,974 posts

186 months

Wednesday 5th September 2012
quotequote all
100k is absolutely nothing for a modern engine if it's been taken care of.

My E28 M5 has 198k on it. If I calculated correctly about 2,500 of those miles were done on a track (myself and the previous owners did lots of track time with the car) Every time I drive it I take it right to 7k once it's warmed up and the engine is like new inside. It's had Mobil 1 15W50 every 3,500 miles since new and fresh oil after every track day.

The reason modern cars last so well isn't down to the engines as much as its down to the lubricants. 50 years ago cars would need valve jobs at 50k and rings and bearings well before 100k. Proof? I know someone who rebuilt the 292 Y Block V8 in his 58 Ford using NOS rings, bearings, etc and gives it fresh oil every 3k miles. He drives it 15k miles a year and 10 years after the rebuild the engine runs perfectly and isn't burning oil. When they were new Y Blocks were famous for slugging up and having serious cylinder head oiling issues because of this. It wasn't the engines fault, it's because engine oils used to suck and they have improved exponentially over the years.

Edited by Captain Cadillac on Wednesday 5th September 03:07

Vince70

1,939 posts

193 months

Wednesday 5th September 2012
quotequote all
It also depends on engine size etc, a good large detuned petrol N/A engine size will last 3 times as long as a small turbo charged unit.

Just ask a smart car owner who's had a new set of rings and turbo at 50.000 miles.

Also applies to wankel engines.

Pints

18,444 posts

193 months

Wednesday 5th September 2012
quotequote all
My FiL took his mk2 8v 2.0L GTI to well over 350k kms and it was still an excellent motor when he sold it.
My Golf TDI is rapidly approaching 110k miles and is still as tight as a drum.

Both cars are/ were serviced regularly. Herein lies the key IMO.

anonymous-user

53 months

Wednesday 5th September 2012
quotequote all
My Matra Murena has done 132,000 miles and is still going like a Southampton Slapper on Royal Navy Pay Day.

Matt UK

17,649 posts

199 months

Wednesday 5th September 2012
quotequote all
Breadvan72 said:
My Matra Murena has done 132,000 miles and is still going like a Southampton Slapper on Royal Navy Pay Day.
laugh

J4CKO

41,287 posts

199 months

Wednesday 5th September 2012
quotequote all
There is a perception that diesels last longer than petrols, I think nowadays this is old information, they used to when they were tough ex commercial engines, low revving, simple heavy things but since the modern diesels have come in with higher pressures and various emissions controls, plus the dual mass flywheels they seem to destroy it isn't as simple, the engine bores and oily bits may survive but the bits around it give up and cost a fortune.

Also having vastly more torque seems to foster a lunging driving style as we all like that nice solid shove, this is harder on brakes, suspension and drivetrain so diesels seem to wear out components more readily, tyres as well.

Chap at work had a Passat and has got rid due to the various issues and cost, replaced by a petrol Avensis, which I reckon, overall will be cheaper to run, another chap has an S max which needed a new turbo at 60 k as the vanes went on the variable vane bit, another has an Audi A4 diesel that is being replaced piece by piece.


So a 100k diesel, for me would be more of a risk than a standard petrol motor, the diesel is usually nicer to drive than say a 1.6/2.0 petrol, think the economy thing influences a lot of people more than it should, total cost should be looked at, that is why I recommend a petrol V8, one good episode of diesel "Bork" these days and you may as well have been running one.



RizzoTheRat

25,085 posts

191 months

Wednesday 5th September 2012
quotequote all
My last 2 cars, both diesels, did 196000 before the radius arm bearings went, and 145000 miles before the heater matrix went. On both cases the engines were running fine but the problems weren't economical to repair. Mind you they were both French so known for their unreliability hehe
I'd be inclined to say its often not the engine that will let you down, do petrol or diesel won't make much difference.

excel monkey

4,544 posts

226 months

Wednesday 5th September 2012
quotequote all
J4CKO said:
the economy thing influences a lot of people more than it should, total cost should be looked at
When you say total cost, do you mean stuff like residual values and VED?

The people who know best about high mileage durability are fleet managers. Any of them on here? If "OMG DIESEL BORK" is such a massive cost, how come the fleets carry on buying so many diesel cars?

Edited by excel monkey on Wednesday 5th September 10:15

Alex

9,975 posts

283 months

Wednesday 5th September 2012
quotequote all
jbi said:
lets take the volvo 2.5 and jeep 4.0 I am currently driving. (both petrol)

At the moment both are around 100k miles and "just run in" IMO

I fully expect them to last well beyond 200k with regular oil changes.

As for modern diesels... wouldn't touch them with a barge pole. Too much emissions related crap, expensive injectors and fuel pumps and very costly when they do go wrong.
Have you had any transmission issues with your Jeep?

bakerstreet

4,755 posts

164 months

Wednesday 5th September 2012
quotequote all
rallycross said:
A one owner 3 yr old petrol car that has done 150k motorway miles is just run in.

A one taxi owner 3 yr old diesel that has done 90k miles mini cabing in London will be worn out.

The friends who told you a 100k mile petrol will be worn out are either misinformed or stupid.
How does a London Cab manage 500k in its lifetime then? Same trhing for London Ambulances. 150k of hard abuse before they are moved onto other duties.

kambites

67,462 posts

220 months

Wednesday 5th September 2012
quotequote all
I don't think the engine is really a major concern when it comes to mileage any more - if properly serviced, there aren't that many wear-related failures on modern car engines. Things like suspension and steering systems are more of a concern for me on high-mileage cars.