I'm kinda surprised to hear the oil consumption posts here... I am doing annual changes since I can't quite hit the 7,500 limit so usually around 6K miles. If mine is using anything it is so negligible on the dipstick I don't notice. I have never had to add any oil between oil changes other than the realization 7 years ago that a full oil change wasn't a top level marker on the dipstick. I will continue to use my Mazda 0W-20 Moly.
Oil Choice, oil consumption
- Thread starter ColoradoDriver
- Start date
- :
- Plano, Texas, USA
More oil consumption issue has been found on 2021 2.5T which triggered the Low Oil Level Warning Light in dash before the scheduled oil change.
Low Engine Oil Warning Light on new CX-5
There’s a new oil consumption TSB on 2021 2.5T:
TSB No.: 01-012/21 CHECK ENGINE LIGHT ON WITH DTC P250F:00 DUE TO LOW ENGINE OIL LEVEL
IMO..disappointed… I have been adverse to turbos since bad experience with a turbo Mitsubishi of 80s vintage in early 90s. I was opening myself to entertaining another one but these reports shut me down again.
1
181962
I've been spoiled by vehicles burning / leaking no oil whatsoever: 2004 Sienna @ 150,000 miles when traded, 2006 Accord V6 @ 100,000 miles when traded, 2014 Sienna @ 100,000 miles so far with years to go. I think the last time I added oil to a vehicle was my 1996 Chrysler JXi convertible (small block 6 cyl Mitsu engine) was probably a service underfill. I've checked oil right after oil changes since then. That car was traded at 100,000 miles. Before that I don't think my 1992 Mitsu Expo burned any oil either over 12 years / 120,000 miles, though that's stretching my memory.
CX-5 2.5L non-turbo? Down about 1/4 quart when measured after sitting for 24 hours. Down about 1/8 quart after 5 minutes of cool down, @ 4,300 miles since last oil change. I'm not bothering with a top off. The 5 minute cool down is closer to the condition when the oil was changed. I was in and out pretty fast that day and it read full when I got home after a 5 minute cool down.
1/8 quart over 4,300 miles? I don't like it because I'm spoiled but in the final analysis it's not anything I'm going to worry about unless it gets worse.
CX-5 2.5L non-turbo? Down about 1/4 quart when measured after sitting for 24 hours. Down about 1/8 quart after 5 minutes of cool down, @ 4,300 miles since last oil change. I'm not bothering with a top off. The 5 minute cool down is closer to the condition when the oil was changed. I was in and out pretty fast that day and it read full when I got home after a 5 minute cool down.
1/8 quart over 4,300 miles? I don't like it because I'm spoiled but in the final analysis it's not anything I'm going to worry about unless it gets worse.
I would be fine with 1/8 qt too.. the one quart adds give me pause though
I was early VQ35DE which are known oil burners as well…worst I ever got out of my ‘02 Maxima (purchased new) was around 1/8 qt in 5K miles
I was early VQ35DE which are known oil burners as well…worst I ever got out of my ‘02 Maxima (purchased new) was around 1/8 qt in 5K miles
1
181962
Yeah, if I burned a quart between scheduled oil changes that would be a concern regardless of what a manufacturer might say which is typically, "that's normal". As for early adoption, the JXi was my last. I've since gone with seasoned generations with seasoned power trains and that that has served me well. I probably shouldn't say this again, but CX-50 buyers will be taking a risk, New model, new plant, new workforce. At least the powertrains are hold overs.
Last edited by a moderator:
- :
- Plano, Texas, USA
The only problem to me is if the engine is burning ⅛ ~ ¼ quart per 4,300 miles when new, it usually would get worse when the engine is accumulating more miles.
Not to mention the oil burned has to go to somewhere, your expensive catalytic converter!
This isn't unique to Mazda .. I don't find these 1-2K mile intervals acceptable.
- :
- Plano, Texas, USA
My 2.5L NA uses about ⅛ quart oil between oil changes (5,000 ~ 6,000 miles).
And “VQ35DE”?
Funny 
VQ35DE.... that was engine in my '02 Maxima.. my VQ35HR in my '07 Infiniti G35x I purchased new doesn't use anything at 112k miles.... literally on the high dot ..even let a few oil changes stretch to 6K miles... normally 4-5K miles.
VQ35DE.... that was engine in my '02 Maxima.. my VQ35HR in my '07 Infiniti G35x I purchased new doesn't use anything at 112k miles.... literally on the high dot ..even let a few oil changes stretch to 6K miles... normally 4-5K miles.
1
181962
I'm not worried about it. If it gets worst then I will.
- :
- Pueblo county CO
- :
- CX-5 Sport 16.5 6M
I've read that thinner, lower tension oil control piston rings in some more recently designed engines can leave more oil on the cylinder surfaces.
These engines are designed for improved fuel economy
I think some oil on the cylinder walls needs to remain to prevent cylinder wall scoring, especially on a cold start perhaps.
I found this on the web...
"
The problem is more pronounced when rings or cylinders are badly worn or damaged, but it can also occur if the cylinders were not honed properly (out-of-round or surface finish defects) when the engine was built (or rebuilt) or if the rings were installed improperly.
Much of the oil that is transported through the piston ring-pack and along the liner usually occurs during the compression stroke. The oil control ring scrapes the oil from the cylinder wall. The scraped oil flows to the ring drain holes/cavities.
Oil left behind on the cylinder wall is needed to lubricate the compression rings. "
Not all oils of the same viscosity are equal from the standpoint of volatility (risk of evaporative loss). Some lubricants may exhibit as much as a 50-percent greater loss from volatility than others. This is influenced by the base oil’s molecular weight distribution.
Three different engines (Class 8, long-haul service) at different oil change intervals show a clear relationship between oil health and oil consumption. One can conclude that as oil ages, the effects of aging (high soot, loss of dispersancy, additive depletion, insolubles, viscosity-index shear, dirt load, etc.) impair the ability of the engine to retain the oil during service.
Fresh new lubricants have more volatile light-end molecules and are more prone to hydrocarbon emissions. As the oil ages, the hydrocarbon emission levels off but can pick up again if the oil becomes contaminated with fuel (fuel dilution), such as from short run times or long idles.
These engines are designed for improved fuel economy
I think some oil on the cylinder walls needs to remain to prevent cylinder wall scoring, especially on a cold start perhaps.
I found this on the web...
"
Causes of High Oil Consumption
Understanding oil transport mechanisms is necessary to prevent oil from going where it shouldn’t. Loss of engine oil is influenced by the engine’s design and the operating conditions. Oil consumption primarily occurs near or through the combustion chamber, either downward through valves or upward past the piston ring-pack.Oil Mobility and Consumption Through Engine Valves
Oil collecting on the stems of intake valves is sucked into the combustion chamber during normal operation. Hot exhaust gases burn oil on stems of the exhaust valves. If there’s too much clearance between the valve stems and guides, the engine will suck more oil down the guides and into the cylinders. This could be caused by valve guide wear and seals that are worn, cracked, missing, broken or improperly installed. The engine may still have good compression but will burn a lot of oil.Oil Flow Through the Piston Ring-pack
Engine oil is designed to produce an oil film on the cylinder walls. While the oil control ring on the piston squeegees much of it off, a thin film will still remain. When the engine decelerates, high negative pressures suck oil in the combustion chamber and out the exhaust manifold.The problem is more pronounced when rings or cylinders are badly worn or damaged, but it can also occur if the cylinders were not honed properly (out-of-round or surface finish defects) when the engine was built (or rebuilt) or if the rings were installed improperly.
Much of the oil that is transported through the piston ring-pack and along the liner usually occurs during the compression stroke. The oil control ring scrapes the oil from the cylinder wall. The scraped oil flows to the ring drain holes/cavities.
Oil left behind on the cylinder wall is needed to lubricate the compression rings. "
Cylinder Wall Oil Evaporation
As much as 17 percent of total oil consumption is associated with liner wall evaporation. The more distorted (out-of-round) and rough (surface finish) the cylinder liner, the more oil film that will remain on the liner after the power stroke. High liner surface temperatures (80-300 degrees C) will cause a loss of this oil by misting and evaporation. Light oil molecules are more prone to evaporation. These light molecules are the first to deplete, and as a result, there is less evaporative loss toward the end of the lubricant’s service interval.Not all oils of the same viscosity are equal from the standpoint of volatility (risk of evaporative loss). Some lubricants may exhibit as much as a 50-percent greater loss from volatility than others. This is influenced by the base oil’s molecular weight distribution.
Oil Change Interval Effect
Extended oil drains are an ever-growing trend. While there are clear advantages (lower oil change costs, higher productivity, environmental benefits, etc.), there are also engine life risks, fuel economy risks and oil economy penalties. A recent study on the effects of the oil change interval on miles per quart of oil is shown in Figure 3.Three different engines (Class 8, long-haul service) at different oil change intervals show a clear relationship between oil health and oil consumption. One can conclude that as oil ages, the effects of aging (high soot, loss of dispersancy, additive depletion, insolubles, viscosity-index shear, dirt load, etc.) impair the ability of the engine to retain the oil during service.
Fresh new lubricants have more volatile light-end molecules and are more prone to hydrocarbon emissions. As the oil ages, the hydrocarbon emission levels off but can pick up again if the oil becomes contaminated with fuel (fuel dilution), such as from short run times or long idles.
- :
- Plano, Texas, USA
Oil consumption is a complicated issue. The oil rings design can be one of the many. The excessive oil consumption (1 quart per 800 ~ 1,000 miles) on my previous 2001.5 VW Passat GLX 2.8L V6 is caused by oil rings on pistons installed upside down!I've read that thinner, lower tension oil control piston rings in some more recently designed engines can leave more oil on the cylinder surfaces.
These engines are designed for improved fuel economy
I think some oil on the cylinder walls needs to remain to prevent cylinder wall scoring, especially on a cold start perhaps.
I found this on the web...
"
Causes of High Oil Consumption
Understanding oil transport mechanisms is necessary to prevent oil from going where it shouldn’t. Loss of engine oil is influenced by the engine’s design and the operating conditions. Oil consumption primarily occurs near or through the combustion chamber, either downward through valves or upward past the piston ring-pack.
Oil Mobility and Consumption Through Engine Valves
Oil collecting on the stems of intake valves is sucked into the combustion chamber during normal operation. Hot exhaust gases burn oil on stems of the exhaust valves. If there’s too much clearance between the valve stems and guides, the engine will suck more oil down the guides and into the cylinders. This could be caused by valve guide wear and seals that are worn, cracked, missing, broken or improperly installed. The engine may still have good compression but will burn a lot of oil.
Oil Flow Through the Piston Ring-pack
Engine oil is designed to produce an oil film on the cylinder walls. While the oil control ring on the piston squeegees much of it off, a thin film will still remain. When the engine decelerates, high negative pressures suck oil in the combustion chamber and out the exhaust manifold.
The problem is more pronounced when rings or cylinders are badly worn or damaged, but it can also occur if the cylinders were not honed properly (out-of-round or surface finish defects) when the engine was built (or rebuilt) or if the rings were installed improperly.
Much of the oil that is transported through the piston ring-pack and along the liner usually occurs during the compression stroke. The oil control ring scrapes the oil from the cylinder wall. The scraped oil flows to the ring drain holes/cavities.
Oil left behind on the cylinder wall is needed to lubricate the compression rings. "
Cylinder Wall Oil Evaporation
As much as 17 percent of total oil consumption is associated with liner wall evaporation. The more distorted (out-of-round) and rough (surface finish) the cylinder liner, the more oil film that will remain on the liner after the power stroke. High liner surface temperatures (80-300 degrees C) will cause a loss of this oil by misting and evaporation. Light oil molecules are more prone to evaporation. These light molecules are the first to deplete, and as a result, there is less evaporative loss toward the end of the lubricant’s service interval.
Not all oils of the same viscosity are equal from the standpoint of volatility (risk of evaporative loss). Some lubricants may exhibit as much as a 50-percent greater loss from volatility than others. This is influenced by the base oil’s molecular weight distribution.
Oil Change Interval Effect
Extended oil drains are an ever-growing trend. While there are clear advantages (lower oil change costs, higher productivity, environmental benefits, etc.), there are also engine life risks, fuel economy risks and oil economy penalties. A recent study on the effects of the oil change interval on miles per quart of oil is shown in Figure 3.
Three different engines (Class 8, long-haul service) at different oil change intervals show a clear relationship between oil health and oil consumption. One can conclude that as oil ages, the effects of aging (high soot, loss of dispersancy, additive depletion, insolubles, viscosity-index shear, dirt load, etc.) impair the ability of the engine to retain the oil during service.
Fresh new lubricants have more volatile light-end molecules and are more prone to hydrocarbon emissions. As the oil ages, the hydrocarbon emission levels off but can pick up again if the oil becomes contaminated with fuel (fuel dilution), such as from short run times or long idles.
The oil consumption issue on the 2.5T from many new 2021 Mazda vehicles could be caused by “modified” valve stem seal as Mazda says in the related TSB: “Since this issue has been reported after a valve stem seal modification, it is very likely that valve stem seal damage is causing oil to leak into the combustion chamber.”
TSB No.: 01-012/21 Check Engine Light On with DTC P250F:00 Due to Low Engine Oil Level
Oil consumption for me is speed related, the faster I go at a prolonged time the more oil I burn. If I keep my speeds around 50, then oil consumption is good. It's been like that for both of my CX5s. I'm basically talking about my 27 mile trek to work. I have the option of doing the highway or slower back country roads.
Right now I'm doing an experiment with Ravenol 0w-20 oil and getting fantastic results. It's a true base 4, genuine PAO oil...meaning it's a real synthetic. IMO, 0w-20 is panther piss, as an old tech teacher used to say..
https://www.ravenol.com.au/product.php?code=1111102
Right now I'm doing an experiment with Ravenol 0w-20 oil and getting fantastic results. It's a true base 4, genuine PAO oil...meaning it's a real synthetic. IMO, 0w-20 is panther piss, as an old tech teacher used to say..
https://www.ravenol.com.au/product.php?code=1111102
One of the things I found most frustrating is that the off-the-shelf oils like Pennzoil, Quakerstate, Havoline, etc., don't give you NOACK numbers for 0w-20. Amsoil does and Ravenol, only two that I know of.
- :
- Plano, Texas, USA
For 3X more expensive than most name-brand 0W-20 oils, Ravenol Eco Synth ECS 0W-20 oil has to be better.
But I’d simply try $21.97 / 5 quarts Castrol Edge 5W-30 oil which also approved for SA-G 2.5L NA by Mazda worldwide and see if it reduces oil consumptions.
Warranty requires 0w-20 so I'm not doing the 5w-30. $13.25 per quart...with shipping. Yes, pricey, but not 3X the price. Actually, it was per liter so you're getting more than a quart...
If it makes you feel any better the bottle has a built in spout...lol
Last edited:
I should probably do another Blackstone test.. haven't done one in years on the CX-5... I'm not easy on my CX-5 and like I said before if there is consumption it is trivial. At this point just sticking with the Mazda moly ..whether worth it or not really have no need to experiment at this point. I totally understand if one has consumption though and trying different oils.
