Burning oil, City vs Freeway?

Joined
Apr 29, 2017
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Location
Orange County CA
Hi guys. Is there anything about the nature of City Driving vs. Freeway driving that would cause a car to burned more or less oil compared to the other?

Meaning, if you drive a thousand miles in the city, with its varying speeds and starting and stopping and you burn 10 oz of oil are you just as likely to burn out same 10 oz on the freeway with a roughly constant speed for a thousand miles?

I think that would have something to do with the oil pressure at varying versus constant speed, but I'm not sure which tends to affect it in which direction the most.
Thanks
 
If you get on the highway, set cruise control to (pick a MPH) and stick with that MPH you are likely to burn less oil. And if that MPH is a sane speed, your engine will run cooler and you will exceed EPA mileage.

If, on the other hand, you get on the highway and treat it like a race track passing everything in site, then you are likely to burn more oil than stop and go light throttle operation in the city, and get lower than EPA mileage, and a few tickets, now and again.
 
I would think the cause of the oil burning would dictate whether city vs highway would increase oil consumption. Additionally naturally aspirated vs turbo would also. Alot of variables to consider.
 
Highway oil consumption will usually be higher due to a constant high vacuum condition pulling oil past worn ring packs and valve stem seals on OHV engines. This is especially true of high mileage engines. The dilution/fuel burn off from a vehicle that's been used primarily around down will mimick oil consumption. But after the additional burn off, actual consumption will tend to level off. Occasionally the newfound additional highway usage will benefit the motor and burn off engine waste products. My grandfather (died 1991) owned and operated a Citgo station since the Depression (1930s) used to say "around town exhaust waste winds up in the crankcase, on the highway it goes out the tailpipe".
 
I know my parents previous vehicle, a 2005 Chevy Uplander (3.5 V6) always burned more on the highway. When we would take a trip up to SC you could count on adding a quart when you got there. They sold it a month or so ago and it's still in the area.
 
the 2013 outback with all 3 of its oil burning phases.. much higher oil consumption on highway.
 
My 76 olds 350 v8 and 83 Chevy Caprice 305 v8 both seem to use the same amount with all highway as with mostly city and short trips. But they turn like 1500-1800rpm on the highway.

A 4 cylinder or a v8 towing or climbing severe mountains probably will use more on the highway.
 
Any old car I've owned that burned oil always burned more oil on the highway. I've had 3 different cars that burned oil and on all 3 this was the case.
 
My 56 Chevy Bel Air 265 with stock rear gearing (3:55) has the engine turning 3200 rpm at 75 mph cruise. Runs all day long at that speed. 3 inch stroke means relatively low piston speeds. However oil consumption is roughly 1300 miles per quart. A 60%/40% mix of suburban/highway/secondary road driving (40-60mph) and consumption drops to almost zero.
 
The S38 in my M6 only used oil at 3500 rpm or higher such as when cruising at 80+ mph or on track days. In contrast, the M42 in my Club Sport will cruise all day at 4000 rpm and not use any oil- although it does consume a little in suburban driving.
I just chalk it up to being the nature of the beast(s) and I don't lose any sleep over it.
 
In contrast my old m42 318is didn't burn any oil it just leaked it onto my driveway. My s38 powered e34 m5 Was the same as yours, fine around town but if you romped it on the way to Vegas it would burn some oil. Miss the e30 more sniff sniff.
 
Originally Posted by MCompact
The S38 in my M6 only used oil at 3500 rpm or higher such as when cruising at 80+ mph or on track days. In contrast, the M42 in my Club Sport will cruise all day at 4000 rpm and not use any oil- although it does consume a little in suburban driving.
I just chalk it up to being the nature of the beast(s) and I don't lose any sleep over it.


Probably rings lose oil at higher RPM and load while valve guide seals lose more in stop and go.
 
Every car I had which used some oil always used more on the highway. My guess, higher RPM.
 
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