Has anyone used 0/30 oil in their 4.0?
 

Folks, I buy Castrol Edge 0/30 online for my wife's BMW which gets through more oil than the Jeep!
I get that 10/30 or 5/30 is recommended for the Jeep but has anyone used 0/30? If so, I'm just wondering how much your Jeep used compared with the thicker (cold) oils....
It would just be more convenient, and a bit cheaper, to use the one type of oil for both vehicles.
What do you think?

I think you are only suppose to use that for first break in periods, and not much else unless otherwise specified.

Keep using the suggested oil for your Jeep. Oil isn't something you wanna neglect.

0w barely works well in a rx8, the rotary engine. The L6 would eat 0 up. 10w30, or 10w40 for those high mileage engines.(>220k)

To be fair, though, not much works well in/on/around a RX8.

Haha

I owned 2 rx8s, bought a 04 brand new, ran 0w, died at 34k. Bought a 06, ran 5w, got just over 180k and sold it.

But my point is that the L6 runs much harsher than the rotaries, for break in I agree, change every 1500 miles, but after that stick to recommended 10w

This is from a good article i have. it is way to long to post. A 10W-30 multigrade mineral based oil is made from a 10 weight oil and has VI improvers added to thicken the product in a 212 F engine. It acts as a 30 weight oil when hot. It acts more as a 10 weight oil at startup. I remind you that a 10 or 5 or 2 weight oil is still too thick to provide lubrication at startup. They are all too thick at startup. There is currently no engine oil thin enough to operate correctly at startup. They all cause excessive wear at startup. Again, we are discussing the needs of my single hypothetical engine for around town driving.


Mineral oil:

Oil type...Thickness at 75 F... at 212 F...at 302 F

Straight 30..........250....................10..........3
10W-30...............100....................10........ ..3
0W-30..........There are none in this range......



Synthetic oil:

Oil type...Thickness at 75 F... at 212 F...at 302 F

Straight 30...........100...................10...........3
10W-30.................75...................10........ ...3
0W-30...................40...................10...... .....3

You use 0/30 in your beemer? the recomended oil for my 325XI is 5W30 full synthetic only.
no my honda civic Hybrid calls for 0W20 in winter and summer. BUT 0W30 higher than 90*
i know in Hybrids they want that thin oil to allow for the auto start and stop when ever the ECU calls for it. so the oil must be thin to start in an instant at any temature.
i really would not use it in your XJ at all verry little protection at start up till it warms up.

You are a brave, brave man, good sir! All the reviews I read kinda steered my away from the 8s. Some of the 7s were just plain beautiful, but the 8s were lacking. Especially in the power dept.

The 8s are amazing vehicles if you know what your doing. What other vehicle can be revved to 9k and sound amazing like the 1.3L turbo?

Toyota's 1.8L hits 9k, sounds like a F1 car with an intake and exhaust.

My 2.0 GSX had the rev limiter bumped to 9k, that thing was just plain sex when wound up.

I know this last one is like comparing apples to oranges but my FZR600R sounds goddamn gorgeous to 14K, and once I get a replacement the turbo kit is getting installed on top of slightly lower compression pistions.

The 8s may hit 9k, but they were SERIOUSLY underpowered. Not to mention the seals will blow if you look at them wrong, let alone add more boost.

I'll give them the benefit of the doubt, but only because they have a perfect 50/50 f/r weight ratio. Sick in the twisties.

I put a type III in my second rx8, got me just above 340whp.

Type II turbo? Who makes it?

Got any pics?

That's exactly right. The only difference is the startup thickness. The thinner the oil at startup, the less strain it puts on the engine and starter prior to reaching operating temp.


Oil on the surface of parts does not lubricate. It is the FLOW of oil between parts that lubricates A thinner oil allows for better flow, thus lubricating better. Modern synthetic oils cling to parts better as they have higher film strength than mineral oils. Synthetics are thinner overall and they have greater slipperiness, Yet they stick better to engine parts.


So....yes 0w-30 or 5w-30 will work fine in your jeep and it will love you for it. Just make sure to stick with an SAE-30 oil.

Mazsport type III, sadly I dont

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