Just curious...

[darylfelsberg]

What oil and filter do you prefer in your PRV? I'm changing it this afternoon, and was curious as to what everyone was using and why. Brand, weight, etc.

[Jonathan]

I use Castrol 20W50 and the replacement filters from DMC (with a new sealing washer included for the drain pan plug).

The manual calls for 20W50 above 20 deg C, which it is often here, but not always. I have not had any issues yet interesting to see the ones listed from -20 deg C to +40 deg C and maybe I should be considering that. I don't doubt that if you use an oil that stays thin at certain temperatures you might so more leaks under your car. My oil pressure warning light sender will leak at times and others it doesn't. This might be why.

No real reason I chose Castrol other than it's a decent brand and the price is right (for the 5 litre jug and two 1 litre ones that often go on sale here).

[Rich]

What's always on/in ours?

Filter: Bosch 72150
Oil: 10W/40 - we don't have >40C driving weather here - use your judgment for TX driving conditions + info below

Recommend following the mfgr's recommendation on oil specs - see p.25
LINK: http://dmctalk.org....DeLorean-Owners-Handbook

[NightFlyer]

For filters, it depends:

If I'm running concours, then it's the stock/OEM Purflux.
All other times, it's the Bosch 72150.

For oil, I prefer John Deere Plus-50 II 15W-40.

Even though it's a diesel oil, the additive pack contains a good amount of the things we'd want, and the lowest levels of the things that we wouldn't want, of all the diesel oils I've looked at.

If the JD oil is too difficult to get, then I prefer Shell Rotella T Triple Protection 15W-40, premised upon the same principles as with the JD oil.

[jawn101]

Cue religious debate. Castrol 20W50 and DMCH Bosch filters only for this guy. The filters are a pretty good deal from them in 6 packs so I just toss some on an order when I need em.

[Michael]

Cue religious debate. Castrol 20W50 and DMCH Bosch filters only for this guy. The filters are a pretty good deal from them in 6 packs so I just toss some on an order when I need em.

Ditto...to the letter.

[Rich]

For oil, I prefer John Deere Plus-50 II 15W-40.

Even though it's a diesel oil, the additive pack contains a good amount of the things we'd want, and the lowest levels of the things that we wouldn't want, of all the diesel oils I've looked at.

Have you considered industry-sourced information such as the following as part of your decision to run "C"-spec (compression-diesel service) motor oil instead of "S"-spec (spark ignition engine) motor oil in your spark ignition D? It says that "C" motor oil has more ZDDP in it than a gas-engine catalyst is designed to tolerate and that the zinc in the ZDDP will poison the cat. It also says that C-spec oil runs higher detergent levels, levels that are too high for gas engines thus causing piston ring problems. It also goes into a viscosity problem but I left that out here.

From Machinery Lubrication magazine:

A catalytic converter is a housing that contains porous metal filler located between the engine and muffler in the exhaust system.....Some of the byproducts of combustion (lead, zinc and phosphorus) can severely cripple the converter’s ability to perform this job. Therein lies the first major difference between the oils. Diesel engine oils have a higher anti-wear (AW) load in the form of zinc dialkyldithiophosphate (ZDDP). The catalytic converters in diesel systems are designed to be able to deal with this problem, while the gasoline systems are not. This is one of the main reasons you don’t want to use a diesel engine oil in your gasoline engine.....

Diesel engine oil has more additives per volume. The most prevalent are overbase detergent additives. This additive has several jobs, but the main ones are to neutralize acids and clean. Diesel engines create a great deal more soot and combustion byproducts. Through blow-by, these find their way into the crankcase, forcing the oil to deal with them. When you put this extra additive load in a gasoline engine, the effects can be devastating to performance. The detergent will work as it is designed and try to clean the cylinder walls. This can have an adverse effect on the seal between the rings and liner, resulting in lost compression and efficiency.

LINK: Article comparing-gasoline-diesel-engine-oils-

[NightFlyer]

Have you considered industry-sourced information such as the following as part of your decision to run "C"-spec (compression-diesel service) motor oil instead of "S"-spec (spark ignition engine) motor oil in your spark ignition D? It says that "C" motor oil has more ZDDP in it than a gas-engine catalyst is designed to tolerate and that the zinc in the ZDDP will poison the cat. It also says that C-spec oil runs higher detergent levels, levels that are too high for gas engines thus causing piston ring problems. It also goes into a viscosity problem but I left that out here.

From Machinery Lubrication magazine:

A catalytic converter is a housing that contains porous metal filler located between the engine and muffler in the exhaust system.....Some of the byproducts of combustion (lead, zinc and phosphorus) can severely cripple the converter’s ability to perform this job. Therein lies the first major difference between the oils. Diesel engine oils have a higher anti-wear (AW) load in the form of zinc dialkyldithiophosphate (ZDDP). The catalytic converters in diesel systems are designed to be able to deal with this problem, while the gasoline systems are not. This is one of the main reasons you don’t want to use a diesel engine oil in your gasoline engine.....

Diesel engine oil has more additives per volume. The most prevalent are overbase detergent additives. This additive has several jobs, but the main ones are to neutralize acids and clean. Diesel engines create a great deal more soot and combustion byproducts. Through blow-by, these find their way into the crankcase, forcing the oil to deal with them. When you put this extra additive load in a gasoline engine, the effects can be devastating to performance. The detergent will work as it is designed and try to clean the cylinder walls. This can have an adverse effect on the seal between the rings and liner, resulting in lost compression and efficiency.

LINK: Article comparing-gasoline-diesel-engine-oils-

Actually, that is a valid concern if we're talking about diesel oils that are formulated for higher sulfur/ash diesel fuels. With the new 15ppm standard of ULSD (ultra-low sulfur diesel), the diesel oils spec'd for such are actually pretty similar to oils formulated for gas engined vehicles, and often meet the same specs.

Take the JD oil that I use for example - this direct from the product's webpage:

Exceeds API SM performance level for gasoline engines.

I was extremely careful and thorough in analyzing the make-up of the additive packs contained in all the diesel oils that I looked at, which is why I run what run and can fully recommend them without reservation.

In essence, when you're considering running a diesel oil in a gas engine, here's what to look for as far as the composition of additives contained in the base oil:

Calcium (detergent) - Lower the better
Magnesium (detergent) - zero to as low as possible (more calcium is preferable to more magnesium)
Phosphorus (anti-wear agent) - only an issue if concerned about cat converter performance
Zinc (anti-wear agent) - 1,200 PPM optimal (any more than that and cat converter performance is effected)
Boron (anti-corrosion and anti-oxidant) - around 100PPM is optimal
Molybdenum (anti-wear) - some is good (helps fill in imperfections in cylinder walls), but too much can clog tight passages and cause accelerated wear

Here are the relevant specs for the JD oil that I use:

2,877 PPM Calcium
13 PPM Magnesium
1,103 PPM Phosphorus
1,164 PPM Zinc
127 PPM Boron
89 PPM Molybdenum

And here are the relevant specs for the Shell Rotella T Triple Protection that I alternatively use:

2,488 PPM Calcium
8 PPM Magnesium
1,108 PPM Phosphorus
1,147 PPM Zinc
37 PPM Boron
8 PPM Molybdenum

Bill R. prefers to run Chevron Delo 400, which has the following relevant specs:

3,396 PPM Calcium
20 PPM Magnesium
1,284 PPM Phosphorus
1,350 PPM Zinc
143 PPM Boron
253 PPM Molybdenum

The JD oil that I run is actually manufactured for JD by Chevron.

Thanks for asking!

[darylfelsberg]

Thanks for the input, anyone ever use the Mobile 1 205 Oil Filter? Seems well made, and according to the crossover list, it is supposed to fit. Anyone use one?

[Tillsy]

Penrite 20W60 here