Seems like every few months there is another thread on here related to which oil to use and/or what is "best" with no definitive answer. With all the posts I have yet to hear of someone saying that their engine got toasted because they used the wrong oil or synthetic when they should have used dino or vice versa. I guess what I am trying to say is that it seems like if you use the proper weight and some kind of name brand as long as you change it regularly any real or perceived differences might show up long after the car would be traded in on something else after a couple hundred thousand miles. Maybe we can move on to something more useful, like what chip off of E-Bay is best to get massive amounts of extra horsepower and improved MPG.

 

^ And we have a winner.

 

Bravo!

I've been 'tracking' engine reliability and durability for approx 30 years looking and hoping to see a clear advantage to using synthetics over standard oils. I've seen no trace of any trend whatsoever. Most cars die of old age before their engines give up and for the engines that do need to be rebuilt, the deterioration rarely has anything to do with oil or lubrication. There's just as many 'blown up' engines with synthetics as with regular oil.

 

Give that man a beer!

Which is the best beer by the way?

 

I'll glady take a beer(beers). After al,l I AM from Milwaukee.

A cold Pabst is hard to beat for me. Not saying it's the best, but before you all laugh, actually try one. Kind of reminds me of the X actually. People give it a bad rap, but those in the know appreciate what a good bang for the buck it is.

 

Find a link to a really good article at CarCraft on Synthetic vs. Conventional, Synthetic Versus Conventional Oil- Car Craft Magazine
I found it enlightening...

 

Oh, that article again.

It's one of hundreds that have been published over the decades that help people achieve their self fulfilling goal of finding 'proof' that one is better than the other, or better said- the other stuff is bad.

If you read it carefully and are familiar with an engine dyno, the small differences found can simply be attributed to variabilities from one run to the next. I've seen bigger differences running the same engine run after run and making NO changes whatsoever.

There's a few key quotes that make me wonder about the value of such articles:

"By contrast, conventional oils contain small amounts of sulfur, wax, and asphaltic material that can promote detonation"...........

Huh? Detonation?


"Or the potential for extended engine life?"

Potential? Why even mention this if the goal was to prove that one is better than the other.

The best part is a bit of sleight-of-hand apples and oranges comparison. The factory fill of 20W50 conventional is compared to 10W30 conventional and 0W30 synthetic. They found that the engine was up 7HP with the 10W30 and 10HP with 0W30 over the factory fill. No comparison was done with same viscosities of conventional syn. vs. conventional, yet the article closes with the inference that the syn. will give 10HP over conventional.

No wonder people are confused!

 

I'm confused... Are you agreeing or disagreeing with synthetic warning?

Maybe I'm missing something but I looked at the link you specified (the relevant page for a '05 X Type downloaded from Topix) and I do not see where it says the "manual warns against synthetics"

All the manual states is "Do no use oil additives".

I'm confused... Does Jaguar not recommend Synthetic oil?
If so where it the link to this statement.

Thanks in advance for clearing up this issue.

 

I recently switched to synthetic at 175,000 miles. Why? I did it for ME. I imagine that it does a better job and feel that I am doing the most for my car. An emotional decision. I personally believe that all the arguments about "not switching back" and "don't use synthetic" etc. have marketing as their motivation vs. science. A fluid that doesn't break down makes SENSE to me. At the first sign of an adverse effect, I will post back.

 

>I recently switched to synthetic at 175,000 miles.

Keep a look-out for leaks, synth seems to be able to get out of much smaller holes than dyno-lube. Aging seals and gaskets that were still mostly tight for conventional oil may allow the slipprey-er synth to get.
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Jaguar: Grace, Pace, and Space - Sir William Lyons

 

Pennzoil Platinum is what I use.

 

I switched to synthetic oil and I had problems with leaks that cost me about a half quart of oil between changes. Switched back to Castrol High Mileage with some Lucas and the leaks stopped.

 

The oil seal leak is no longer true with synthetics. Those occured in the days of PAO and POLYOL only oils.

 

I have used Mobil1 for 75K and had good results. Based upon the temp gauge reading the engine runs cooler in the Georgia summer heat as well.

 

When the X400 was introduced to the US market, 10K mile scheduled maintenance was included up to 40K miles. If synthetic oil was recommended then that would have added cost. My guess is that people would have opted for the more expensive oils than Jag was willing to pay for???????????????

Just a cost saving guess!!!

bob gauff

 

I've used Castrol Synthetic since first oil change after buying our X in 2007. I change oil once a year and use a K & N flilter. No problems with engine and no new leaks, in fact the small leak around the pan gasket is actually leaking less.

 

When it comes to synthetic vs dyno oils, you have to consider more than simply 1 factor. An article that you might find of interest is Oil Viscosity - How It's Measured and Reported. This gives you a break down of what viscosity really is and what it does for you. This article doesn't necessarily deal with automobiles, but you can draw logical conclusions from this. The reason why most cars worry about the viscosity is the viscosity involves the thickness of oil left behind as the oil runs off of the various metal parts. A thicker oil will tend to leave more oil behind. More oil would imply more lubricating action as you have more fluid to be used to act as the slippery surface between two pieces of metal. The problem comes with the newer engines, they are leaving less and less space (we are talking down on the 0.001" scale, if not the 0.0001" scale). The higher viscosity oils have bigger molecules, which in some cases can make it so the oil is not able to slip in between the two pieces of metal. This leads to metal on metal contact. As you can imagine, this condition is not good at all. So, atleast to this point, one would think that a thinner oil is better, right? WRONG!!!!! Another property of oil is its ability to not get pushed out from between two metal surfaces (its ability to make a hydraulic wedge). A thicker oil doesn't tend to get pushed out of the way as easy, therefore is more likely to keep the hydraulic wedge between the two metal surfaces. This wedge is what keeps the 2 metal surfaces off of each other, leading to reduced wear of the metal.

So, now comes the question of what oil is the "perfect" oil. Unfortunately, there is no "perfect" oil (if there was, everyone would be using it). It is a now a balance of what properties are you wanting from the oil. Some oils are only there to provide lubrication. Others, like what we need for our cars, not only provide a lubricating function, but also provide a hydraulic function (ie, the variable valve timing). The hydraulic properties of oils very greatly based on their viscosity and the molecular make-up. With dyno oils, since the base is pretty much consistent, it is easier to recommend a certain weight oil and know what sort of hydraulic results you are going to end up with. When you start getting into synthetics, the base part of the oil (what it is made from) varies greatly. Due to this, the hydraulic effects are more open to what they may be. The may be better, they may not be. But, unless you have a PhD in chemistry and have a lab at your fingertips, figuring this out is going to be difficult to do.

Another thing to keep in mind is that atleast in the US, what it takes to call an oil "sythetic" is not very regulated. In Europe, it is very regulated. So, what we in the US pick up at the store as a synthetic motor oil may only be partially a true synthetic oil. The rest of the oil may be a modified form of a dyno oil molecule. That makes it "synthetic" (a product that is not natural in the environment), but at the same time, is it any different than straight dyno oil? Each process alters the physical properties of the oil some. Question is: did it make it better for your application? Again, where is your PhD.

In short, both work in our cars and from our discussions, no problems have been related to the continual use of either oil or even the switching back and forth. The question really comes down to whether you think the additional price of the full synthetic oil is justified. That is a personal call.

If you want to learn a lot about oil, check out a website by a guy doing his own research. This is about as unbiased as you can get. Check out - Bob is the Oil Guy. Probably more information there than most people ever want to know about oil. But, if you are after oil information that isn't biased, I can't think of a website that will be more of a straight shooter.

 

for turbo charged 1.8 VW for warranty to be honored. WHY you ask? Because this engine is referred to as an "interference engine" with moving parts ( valves etc) that if they don't "get out of the way" in time... Blown engine.
VW says that what causes this is plain old conventional motor oil SLUDGE.
So after learning that, I can't see any way that synthetic isn't a vast improvement over conventional oil.
For 2010 an on Jaguar has now made the use of Synthetic Mandatory.
I spoke with an experienced jaguar Mechanic on the Syn vs Conventional oil question for my 2003 XJR. His answer was simple and direct. He said "If it were my car like that beauty, it would be Synthetic all the way"
Case closed for me.

 

I'm wondering why you bring the topic of interference engines into the never ending debate of dino vs. synthetics?

The reasons that the newest Jags require synthetics has no impact or effect on older models. Apples and oranges.

 

Sludge has nothing to do with an interference engine. When those things "blow" it is because the timing belt broke causing the valves to hit/interfere with the pistons. Both sludge and a broken timing belt are more signs of poor maintenance than anything. I don't understand what point you are trying to make.