7

I've heard that it's "normal" for older cars to burn a certain amount of oil and that it's not really a problem.

My question is how much is too much? At what threshold does burning oil become a problem for an "old" car and how is "old" defined in this case?

Robert S. Barnes
  • 15,708
  • 69
  • 148
  • 239

3 Answers3

5

It is actually normal for brand new and modern cars to consume oil.

There is no set number, but as a rule of thumb, it's often agreed that up to about 1 quart or 1 litre of oil per 1000 miles (e.g. out of 6L of oil from the oil pan) is considered to be an entirely normal oil consumption rate; on the other hand, more than 1L per 1000 km is probably too much of an oil consumption.

As others mentioned, this is not to be confused with oil leaks, where the oil leaks onto the ground from beneath the engine -- no such oil consumption should be considered as normal.

cnst
  • 1,515
  • 6
  • 21
  • 33
  • 1
    Looks like good info, any references? – Robert S. Barnes Nov 23 '14 at 17:45
  • It's basically based off of the comments in various forums, where people complain that their brand new sports-friendly car burns half a quart of oil every 1k miles, even after the break-in period, and the dealer won't do anything about it. – cnst Nov 29 '14 at 21:02
  • So after 3000 miles, vehicles are regularly low by 3 quarts of oil? That doesn't sound right at all, and certainly is not my experience. – End Anti-Semitic Hate Apr 04 '15 at 22:10
  • @RockPaperLizard: That's not a regular occurrence. However, it is within the accepted tolerance of the manufacturer. And that's really the only thing that matters since it dictates when the manufacturer/dealership will decide it's severe enough to warrant fixing under a warranty. – Ellesedil Jan 27 '16 at 01:06
  • 1
    @Ellesedil Wow, that's bizarre. After 2000-3000 miles most vehicles would be missing half their oil, and after 4000-6000 miles most vehicles would have no oil in them, and the manufacturer would claim everything is working fine? – End Anti-Semitic Hate Jan 27 '16 at 01:17
  • @RockPaperLizard: Yes. It is the responsibility of the owner to ensure that their vehicle has enough oil for proper operation. So if it's low, they are expected to add more and not wait for their regular oil change. Although in this case, I guess it's essentially just an oil filter change. – Ellesedil Jan 27 '16 at 01:19
  • @RockPaperLizard, noone says about "most"; this is certainly not "most"; also, don't most car manuals actually do say that you're supposed to check oil and tyre pressure at every stop for petrol? E.g., every 200 to 600 miles, which should certainly be enough to add an extra quart/litre of oil, if needed. My Jetta apparently appears to need about 1L every 7k miles on average, for example, but even if it was 1L every 2 or 3K miles (which is what it actually feels like sometimes), I'm pretty sure dealer wouldn't do anything about it, either. – cnst Jan 27 '16 at 02:50
  • 1
    "you're supposed to check oil and tyre pressure at every stop for petrol" - It makes one wonder why no manufacturer or government department cares that 99.9% of car owners are apparently not properly maintaining their vehicles or tyres. Since almost no one actually follows instructions like that (for better or worse), I'm guessing the inclusion of such instructions is just legal CYA and a way for manufacturers to get out of having to pay for warranty repairs. – End Anti-Semitic Hate Jan 27 '16 at 06:12
  • Of course, if those instructions are actually important and are intended to be followed, almost everyone who owns a car needs to be educated and petrol stations need to be equipped to accommodate this essential maintenance. Many petrol stations have no air for tyres, or only 1 compressor for the entire station. They also generally do not have sufficient parking for every custom to check the air in their tires. Petrol station staffing and lighting are often inadequate for checking oil levels, and clean towels are often not present to wipe dip sticks. – End Anti-Semitic Hate Jan 27 '16 at 06:15
  • I have also heard that 1l/1000km of oil is advertised as normal by some manufacturers, but honestly, I've never seen a car that does this that isn't half way to the scrapyard. Even 30 year old cars today only do this when they have a leak, broken turbo or a failed head gasket. Seems like a way for the manufacturer to pass poorly made engines as normal. – I have no idea what I'm doing Jan 27 '16 at 15:01
  • @RockPaperLizard, in California, it is state law that the stations must provide free water and free air to every customer paying for petrol (you usually have to ask the attendant for remote activation, otherwise, the stations will still charge you 1 USD or so); paper towels are generally in good supply, too, but could be scarce depending on how cheap the station is – cnst Jan 27 '16 at 21:16
  • @cnst That is not applicable for me, but what you describe is a great model the rest of the world could follow! – End Anti-Semitic Hate Jan 29 '16 at 00:12
  • If there were a common need to check oil that frequently, I would think that cars would routinely include a dashboard indicator to indicate when the oil level was getting marginal but wasn't yet critical. – supercat Feb 14 '16 at 07:56
  • @supercat, very funny! Have you ever heard of Unsafe At Any Speed? :-) – cnst Feb 14 '16 at 19:19
  • @cnst: Someone who had to spend thousands repairing an engine because the oil got unexpectedly low would likely be willing to spend extra on his next car for a system that would check the oil level automatically. If cars routinely burned that much oil, the number of people willing to pay for that feature would be pretty significant. – supercat Feb 14 '16 at 23:29
  • @supercat, engines will still run fine with very little oil, if you change your oil every 5K miles, even if it's missing half the oil (missing less than half might actually give you a better MPG!), it's unlikely any repair will ever be necessary. A noticeable reduction in MPG will come first (when more than half the oil is missing); adding oil will likely bring MPG back to what it was. – cnst Feb 15 '16 at 02:01
  • Yeah my 97 Integra eats about a quart every 2k miles and apparently that's pretty good. – Sentinel Jun 09 '18 at 08:18
1

If oil is below 3/4 after 6 months or after 10000km then its too much. Are you using the recommended graded oil? Check with Repco or BNT if you have it in your country or your local parts dealer not a mechanic unless its the cars dealership.

CarlJB
  • 155
  • 4
0

I have a 2001 Lexus GS300 with 285,000 km on the clock. I buy six litres every oil change; five for the change and use the remaining one litre over the next 10,000 between oil and filter changes. I think that's reasonable. Pete

PETE SMITH
  • 1