CRD engine oil
 

I'm just about to perform my 120k service for 2009 JK.

I know it's a bit of a debate online but thought I'd ask and see what experiences guys on ausjeep have had.

I normally put 5w/40 but I've heard 10w/40 is supposed to better appearently it helps if your engine heats up when towing, is this true and is there any other benefits or negatives?


, [____],
l----L -OlllllllO-
()_) ()_)-------)_)

The two parts of the viscosity rating in Multigrade oil denote the cold (winter) viscosity and the viscosity at 100C.

5W-40 (W = winter) is good for really cold snowy winters but there shouldn't be much, if any difference between 5W-40 and 10W-40 at 100C temperature.

IMHO, a 40 oil is the sweet spot for most diesels. I don't know the CRD engine well but I don't reckon going up to a thicker 50 oil is going to help much (if any) when towing and I don't reckon a 30 oil is a good idea.

There is also a price difference to consider and here 10W-40 Mobil Delvac (my favourite) was always a minimum of $20 cheaper than 5W-40.

That reminds me, it's more important to get a good quality oil because they will actually reach their rated viscosity at 100C and their performance won't degrade much at higher temperatures (it's all about the additives).

That reminds me of the reminds me - watch out for off-the-shelf additives because they usually thin the oil.

Does the CRD manual specify the standards to which the oil has to conform? For example, Audi specifies VW 507.00 compliant oil must be used in certain engines, usually because it is a low-sulfur and fully synthetic oil and some of the engine parts were designed to work with those characteristics. Following the standard usually limits the brands and the viscosity that can use to the point where you don't have much choice except for the brand.

Use what the manufacturer recommends. The CRD 3.2L in my 2013 BT-50 TD5Cylinder used Magnatec Professional 10W30.

My TDV8 Landcruiser was Penrite 10W40

And the CRD 3.0TDV6 in the WH Cherokee takes Penrite 10W40 (however when new 5W30).

You will have conformance recommendations, and I would run a high quality oil that meets those requirements. If your engine is new, go the 5W30 or 5W40. If it has 100,000klms or more, go with 10W40. I prefer Penrite Extra10 for a good alround quality oil but if my engine was new, I would use Mobile 1, Castrol Edge sport, Nulon and other premium full synthetic oils.

Apologies - I misread the first. If you are towing decent weights etc or running it hard I would definitely use 10W40.

I've got a 2007 2.8CRD in UK
Been using 5W-30 & for the last year 0W-40 which meets the recommendation of whats in the hand book
Now got 73,000 miles (117,000km) on it and now thinks a 10w-40 or 50 would be more beneficial
Apparently the VM Mortori manual for RE428JK7 / RS428JK7.05A - EU4 engines states
-Viscosity grade:SAE 10W-40
-Specifications: ACEA E6

I change it every 6,000 miles (9600kms) anyway so I dont suppose it matters what goes into it

Would be interested in the thoughts of those more knowledgeable on this as I've got an oil change coming up ... thanks

Just keep in mind that manufacturers specs are not solely based on engine protection..... they would sacrifice your engine life in a heartbeat if they could drop another 0.1 ltrs/100km off there submitted fuel consumption ratings. ( US CAFE "Corporate Average Fuel Economy" ) its that important TO THEM.

Its always educational to look at oil recommendations for identical engines over the years... a case in point is the old 3.8. When CAFE came in... suddenly the oil got thinner..... Also accompanied by a surge in complaints about high oil consumption compared to previous vehicles with the same engine.

Make you own choices....... but not blindly :-)

Sounds like 10w40, had a look at penrite they do full synthetic and semi synthetic, what's everyone using?


, [____],
l----L -OlllllllO-
()_) ()_)-------)_)