New 10W30 Diesel Engine Oil

I've never had a problem mixing oils, although I've never used those two specific oils.

I've never been a fan of Canadian Tire oils, as they are basically made by Esso.....I prefer Castrol, and truth be told, so does VW...

- Peter

The only real question is does it meet VW's specifications for your diesel.

VW has some specific requirements for their diesel's oils. They are listed in the manual. I would suggest not using any that do not specify that they meet the specifications listed in your manual. If they do, you should be fine.

NOTE: Not all diesel oils meet those requirements!

The manual specifies that the oil should API Service CD. The Castrol 15W40 is API CF (or more I think) and the Motomaster 10W30 Diesel engine oil is also at least API CH (or more). Both cover API CD.

Thanks,

AJ.

On the mixing oils thread, any comments on using CI-4 and SL rated Rotella synthetic in a gas engine as well as diesel....can I use a single oil for a TDI and a 3.5L SUV (Trooper)? E.g. I assume SL rating means it will work OK, but as a 'best practice' is this stuff not really meant for sparked engines?

If the Trooper can use 5W-40 oil of API SL or any previous API S rating, then the 5W-40 oil with the API SL rating should be fine for it.

The following API ratings can satisfy API CD:

CE, CF, CF-4, CG-4, CH-4, CI-4

Note that CF and CF-4 are different and not interchangeable with each other.

Make sure this oil complies with the VW spec in your owners manual before using it!

Only do it in an emergency when the correct oil is not available. Not a good idea for general use.

If it aint broke, do not fix it. Stay with the oil that worked for 380

000km. I would not add a "thinner" oil to an engine that is used to a thicker one.

Toronto Winter temperatures rarely drop below the lower recommended range for the 15w40 Castrol.

I personally change 3 times a year ('91 TD with >250K km), using 5w40 synth in the Winter months (frequent winter trips to Temamagi, which is a BUNCH colder than TO) and either Castrol RX 15w40 or Rotella

15w40 in the more temperate seasons. Before going up North, used the 15w40 dino oil year round, no probs with Winter starting or cranking speeds.

Why bother using Crappy Tire oil when the 15w40 would work? Castrol, Rotella, etc. have a great reputation in the diesel market.

rgds, g. :o)

Where in the world did you get that idea? Mixing different viscosities is fine. You get a mixture of the properties of both. 5W30 + 20W50 would yield something in between, similar to 10W30 or 10W40.

For any turbo motor, I'd suggest going with the oil closest to what's required for the operating conditions until the next oil change. Synthetic oil is probably a good idea to avoid coking in the turbo. But as far as mixing grades all commonly used motor oils are compatible with each other and will mix just fine.

If you're just topping up (i.e. under a quart), use whatever you have handy, or be prepared and keep some of your normal stuff in the trunk. Anything is better than running low on oil.