Do modern engines need running in?

Do modern engines need running in?

Author
Discussion

DartyBistard

Original Poster:

175 posts

119 months

Tuesday 21st July 2020
quotequote all
Curious to know what people's thoughts on this are. I know the temptation when you get a new car is to see what it'll do right from the jump, but do modern engines really require running in like old engines?

I'd have thought that nowadays modern lubricants and machining techniques mean that if the engine is up to temp then rag away to your hearts content, regardless of how new it is....

BrettMRC

4,084 posts

160 months

Tuesday 21st July 2020
quotequote all
If it's a PHEV then potentially how would you get the running in period over in a reasonable timeframe anyway? (Short of not charging it)


Do EVs need to be run in? wink

Tim bo

1,956 posts

140 months

Tuesday 21st July 2020
quotequote all
DartyBistard said:
Curious to know what people's thoughts on this are. I know the temptation when you get a new car is to see what it'll do right from the jump, but do modern engines really require running in like old engines?

I'd have thought that nowadays modern lubricants and machining techniques mean that if the engine is up to temp then rag away to your hearts content, regardless of how new it is....
RTFM

Ron99

1,985 posts

81 months

Tuesday 21st July 2020
quotequote all
Although modern engines are much better than they used to be, I think modern engines still benefit from several 30-60 minute sessions at a steady 70mph.

Quite often my wife and I bought a nearly new car which was a little thirsty on oil but was completely cured after several long fast motorway journeys.

I suspect that cars which haven't done the above are the ones which suffer pre-ignition and wrecked engines, since it has been suggested that excessive oil getting past the piston rings can severely affect combustion. Basically oil lowers the octane of the fuel, making it more prone to knock or pre-ignition, making the engine more prone to piston failure.

My Viva was quite an oil-burner when I bought it at 5k miles, 1yr old. After a few long fast runs it hasn't used a drop of oil in 2yrs. The same basic engine block was used in Vauxhall's disastrous 1.0T engine, of which most have now blown up as a result of pre-ignition. I speculate those blown engines never got a decent run-in, so burned oil, which led to their premature death.

blue_haddock

3,198 posts

67 months

Tuesday 21st July 2020
quotequote all
I got a brand new caddy maxi life in January and wasn't made aware of any running in process. I've just driven it fairly gently for the first month or so and since then driven it normally.

Mpg is definitely increasing slightly with time as it beds in.

anonymous-user

54 months

Tuesday 21st July 2020
quotequote all
Do they need running-in? No

Should you rag them from new? No

Drive sensibly for the first 1,000 miles and all will be fine.

Some modern performance cars automatically adjust the red line on the rev counter during early miles and some automatically limit torque.

NGRhodes

1,291 posts

72 months

Tuesday 21st July 2020
quotequote all
https://www.bmw.com/en/automotive-life/break-in-a-...

BMW said:
Many drivers wonder whether breaking in a new car is still necessary or if this practice has been superseded with the advances in technology. The answer? Yes and no...

Doing an engine break-in used to be a standard procedure with new cars. And it’s still the case that you should avoid running the engine at high RPM for the first 1,300 miles. Experts recommend a maximum 3,500 rpm and 90 mph in diesel models and 4,500 rpm and 100 mph in gas models. This will give the engine and transmission sufficient time to adjust to each other. Once you’ve reached the 1,300-mile mark, you can gradually increase your speed and your engine’s RPM. In particular, avoid to put too much strain on a cold engine. However, that’s true not just when breaking in a new car but for the whole life cycle of your car. Likewise, never turn off an engine that has been running hard. Allow it to cool down by driving a few miles at a gentle pace.

NGRhodes

1,291 posts

72 months

Tuesday 21st July 2020
quotequote all
From my Audi manual:


Car_Nut

599 posts

88 months

Tuesday 21st July 2020
quotequote all
rockin said:
Do they need running-in? No

Should you rag them from new? No

Drive sensibly for the first 1,000 miles and all will be fine.
.
The third bullet point contradicts the first two!

I always believe in running in any new engine gently - In my view one should use no more than half throttle, exceed 3000 rpm, or let the engine Labour (xxxxing IPad spellcheck) at all for first 200 miles, and then gradually loosen this up over the first 1500 miles. Pays dividends later in the car’s life.

cib24

1,117 posts

153 months

Tuesday 21st July 2020
quotequote all
No, they don't but they do loosen up after 1,000-2,000 miles in my recent experience with a 2019 vehicle.

fiju

704 posts

63 months

Tuesday 21st July 2020
quotequote all
Rag it from new. Makes no difference. You'll get more wear from cold starts than from ignoring any break in procedure. If the engine's going to lunch its bearings, it wont be because it hasn't been run in.

Wacky Racer

38,154 posts

247 months

Tuesday 21st July 2020
quotequote all
fiju said:
Rag it from new. Makes no difference. You'll get more wear from cold starts than from ignoring any break in procedure. If the engine's going to lunch its bearings, it wont be because it hasn't been run in.
What a load of cobblers.

Yes, you don't have to "run in" a new car at 40mph like you used to do in the 1960's, but it's common sense to drive sensibly for the first few hundred miles, engines cost thousands of pounds.

UpThe

23 posts

45 months

Tuesday 21st July 2020
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No, it’s leased, so who cares.

CABC

5,575 posts

101 months

Tuesday 21st July 2020
quotequote all
one theory is to warm a new engine up thoroughly but then give it some max revs. avoids piston steps anyway!
i'm sure someone can find the vid on this, it did the rounds a few years ago.

Car_Nut

599 posts

88 months

Tuesday 21st July 2020
quotequote all
UpThe said:
No, it’s leased, so who cares.
The poor sod who buys it a few years down the line. Do you have any conscience or morality?

Buster73

5,060 posts

153 months

Tuesday 21st July 2020
quotequote all
Running in , please pass.

0ddball

862 posts

139 months

Tuesday 21st July 2020
quotequote all
Car_Nut said:
UpThe said:
No, it’s leased, so who cares.
The poor sod who buys it a few years down the line. Do you have any conscience or morality?
It may be tongue in cheek, but that's the attitude the majority of people running a lease will have.

Boosted LS1

21,185 posts

260 months

Tuesday 21st July 2020
quotequote all
Manufacturers have already run it in. That said you still need to allow the brakes to bed in . I'd drive at normal speeds and loads but allow some extra braking distance initially until I get used to the feed back.

Glosphil

4,354 posts

234 months

Tuesday 21st July 2020
quotequote all
UpThe said:
No, it’s leased, so who cares.
I think this if buying an ex-rental car. When it was new do renters treat it as a new car shoulbe treated? I doubt it. d

Mammasaid

3,833 posts

97 months

Tuesday 21st July 2020
quotequote all
Glosphil said:
UpThe said:
No, it’s leased, so who cares.
I think this if buying an ex-rental car. When it was new do renters treat it as a new car should be treated? I doubt it. d
I've treated all leased vehicles as if they were my own, one, so that I return it at the end of the lease and have nothing further to pay and two, so that future owners can have the benefit of number one.

My current Volvo had no specific running in instructions, so I just kept the revs down, avoided full throttle, and varied the revs on long journeys.