Oil change interval - 10k but looks clean!

I drive a 2001 Alfa Romeo small wagon (Europe) with an LPG installation. I now have 10k miles on the oil, and am ready to change it, but, as with the last change, the oil looks practically new. Quite transparent. It is “part synthetic” and just a store brand. I suppose I’ll do the change anyway, but opinions?

Also, I wonder why more people aren’t going LPG. I’ve had it for four years with no issues whatever, and I save half on my cost per mile. In North America I suppose there is an availability issue. You can always drive on petrol - the original gas tank is still there, but I suppose installers are few and far between. In western Europe “Autogas” is still quite unpopular, even though we pay around double for gasoline here. There is still a false perception that LPG could damage the engine, and the industry is too small to mount a proper public awareness campaign. In certain countries like Turkey and Poland, where the price is held low by the government, adoption is much higher. Filling is a bit inconvenient compared to petrol, but not a big deal.

You should follow the manufactures recommended change schedule. Clean oil could still be broken down. If you are running LPG the car may be running cleaner than running off of petrol (gas here in the states) leaving the oil cleaner looking. Commercial vehicles are starting to use LPG, but as you say availability is the issue.

Never heard that LPG damages an engine. But I know for a FACT LPG produces about 20% less mpg and 20% less HP/Torque for the same engine running on gas. Talk to the many cities that converted their buses over to LPG or LNG. At first they just converted their existing buses…and many buses on some routes had problems just getting up some hills with a full load. They then bought buses with bigger engines and more HP that were already converted to LPG or LNG.

One of the biggest advantages for LPG/LNG is the extended oil changes. Since the engine burns so clean then very few byproducts contaminate the oil. One utility company in NY that runs all their trucks on LNG have extended oil change intervals of 25k miles with many trucks going well over 150k miles. DO NOT TRY THIS IF USING GAS OR DIESEL.

Filling is a bit inconvenient compared to petrol, but not a big deal.

Here in the US…it’s a HUGE deal. There isn’t a LPG/LNG station within 100 miles of where I live. There is no infrastructure here. The bus companies and Utility companies that run on LPG/LNG have their own stations.

Thanks for your comment.

I was under the impression that burning propane was dirtier for the engine. Maybe I’ll just hold off on that oil change.

“Gas” as a word is a problem in the international world, as, naturally, it usually means something other than a liquid fuel for cars except to Americans. In Germany we say “Benzin” which is also less than ideal.

Personally, I get about 10-15% less fuel economy, but find the loss of power negligible. (I can always switch off the LPG with the touch of a button if I really want to race, but rarely find it necessary or the difference observable). Now, our “autogas” in Europe is a mix of propane and butane, seasonally adjusted, so the energy content is better than with propane alone. In Germany, the cost is a bit below half compared to gasoline, bringing the savings to about 50%, compensating for the lower energy content. I don’t know if this is intentional, but it wouldn’t surprise me. In other EU countries, the “Autogas” is well below half.

You should follow the manufactures recommended change schedule.

Really? On what planet are you living?

LPG is 1/2 price of petrol but has 20-30% less mileage? You spend less $ per mile. Net win.

Cavell, have you learned to cook meat? Make knives and spear points from flint? I envy the exciting journey to the present ahead of you.

“Here in the US…it’s a HUGE deal. There isn’t a LPG/LNG station within 100 miles of where I live.”

Compressed Natural Gas is a problem, but propane? You have to drive 100 miles to fill your bbq tank?

Unfair. Filling a vehicle with LPG is quite a different thing from exchanging a BBQ gas cylinder. A special pump is required. I tank my car at certain stations which offer “autogas”, but I exchange my 5kg BBQ tank at the big box hardware store which has no pump for my car. I wish it did.

Only soot, wear metals, contamination or severe breakdown from heat change the appearance of motor oil.
Viscosity breakdown, additive depletion, acidity. The oil can suffer from these and look perfectly fine.
I wouldn’t go past 10,000 miles.

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Only soot, wear metals, contamination or severe breakdown from heat change the appearance of motor oil.
Viscosity breakdown, additive depletion, acidity. The oil can suffer from these and look perfectly fine.
I wouldn’t go past 10,000 miles.

Thanks! I appreciate the informed and useful response!

Compressed Natural Gas is a problem, but propane? You have to drive 100 miles to fill your bbq tank?

Not one that’s approved by the DOT.

I would do 10k with full synthetic. 2014 Toyota engine oil change are now 10k with full synthetic.

CNG is FAR cleaner than gasoline. That’s why it’s approved to run CNG forklifts, indoors. A fuel that is gaseous at room temps will be naturally cleaner than a volatile liquid (like gasoline)…which will be cleaner than a non-volatile liquid (like Diesel).

We have companies here where you can mail a sample of your oil for a used oil analysis. If you have those there, that sounds like something worth trying in your case.

There are factors other than miles that affect the engine oil and eyeballs are not a reliable method of oil inspection.

OP, you’re also coming across with a bit of an elitist attitude in response to some posters who said nothing offensive.

robobass, just to be clear, I am the one who flagged you for abuse, not Cavell. We all try to help each other here, sometimes we make mistakes, I know I do on occasion, but please do not make a difference of opinion turn into a personal attack. Ridiculing other members is not appreciated and doing so will cause you to lose respect within the group.

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LPG is LPG. Your corner gas station will fill your bbq tank, forklift cylinder, roofing torch, RV tank, or your LPG automobile just the same. It all comes from the same tank and pump.

besides, I am the local luddite…

The problem in the U.S. is the propane conversion process…A whole new intake system must be installed to bypass the existing gasoline injectors… It’s expensive to do this. Today in Denver LPG (Propane) is selling for $3.65-$3.85 a gallon. Gasoline is selling for $3.45. This is street price, taxes paid.

My daughter just had the oil changed in her hybrid Lexus at 10,000 miles as recommended…The old oil looked pretty good for that mileage…technology advances, usually for the better…