Engine Oil Viscosity 3.0l Diesel Engines

[Troutman]

Hmmm....interesting reading this thread. I remember reading there were two grades of oil recommended in the manual for my 2001 4.7 V8, 5W-30 and 10W-30 with the 5W-30 being more the choice in cold climates. In any case I've done my own filter and oil changes since new and have always used Shell Helix Eco 10 which is a semi-synthetic 10W-30, with the Jeep workshop's blessing. I change filter and oil at every 5000 k's so can't see the longer service interval of a full synthetic oil being of much use. What does everyone else run in their V8's?

[Lenfj]

Roscoe, you have certainly made me sit up and take notice, thank you for that. I will discuss my situation further with 'Wayne' head mechanic Adelaide Jeep. I find it extremely interesting that your 2007 manual recommends 5w-30 as apposed to my 10w-40. As I said I have a 99% cure, maybe the 5w-30 will give me 100%. I will be interested to hear what you go with in the final analysis. Regards.

[roscoea26]

Troutman I change my oil every 5,000k even though the fully synthetic has an extended oil change interval what I like about the full synthetic is it has better properties and wear additives.

Lenfj I'll try an remember to let you know what I go with at next oil change but at this stage I'm leaning towards Mobil 1, it is a little more expensive than the others so I would think the reason is it is a cut above the other brands. What I save in doing my own changes makes up for it I guess.

[roscoea26]

I was talking to the service manager at Sunco Motors, Maroochydore today in relation to the best oil to use in my CRD. He advised that Jeep Australia had recently issued a service bulletin advising all Jeep service agents to use Mobil 1 ESP 5W - 30 when performing oil changes on GC WH and Commander CRDs

[Lenfj]

Very interesting roscoe, I booked mine in for 35,000 service Thursday at Adelaide Jeep. They are staying with the Castrol Enduron. I will enquire further when I drop it in as to their 2007 vehicles. Cheers.

[rockski]

Just been trawling over this thread.

So in summary, the current synthetic oil advice for the CRD is ...

i) ex Jeep Aust, Mobil 1 ESP 5W-30
ii) ex BEA, MB Adelaide, Castrol Enduron Low SAP 10W-40
iii) ex Autobarn, Penrite Synthetic performance HPR 0 SAE 0W-40

... or has the choice been further broadened over the last few weeks?

(at least its clearcut for Troutman with the Shell Helix ECO10 in the petrol V

[turbomart]

For the people unsure what the numbers "10w-30" etc mean the low number is the min viscosity (thickness as compared to water. ie 0w=water) & the upper number is the resistance to thinning out at high temp.
For instance a 10w-30 would have a viscosity of 10w cold and would exhibit the same resitance to thinning out as a 3ow oil would when hot.
So you can see the low number is the important one for cold starts with the upper number the higher the better.