When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
My take on the JLR oil dilution issue is that it really isn't as big of a deal in the Discovery V's, in large part because you shouldn't be pushing your OCI's much past 6k to 7k miles anyways. STJLR.03.5005 is a low SAPS 5w30 with a low'ish HTHS in the low 3.0's. Not sure of the specific Castrol specs but because of the low SA requirement (so as not to plug the DPF any further,) the TBN is lower than say a BMW LL-04 or MB 229.51/2 spec oil. Because of this, 6k to 7k is all you want to push your OCI's out to anyways, and that should be ample to offset any dilution of the oil by the SCR.
Modern diesels are actually ideal for city driving because of their low-end torque; they are like an old big-block motor with gobs of torque right off idle.
I do oil changes at 15k. 6-7 is too low for a pure synthetic. I also switched to the Ford F-150 diesels oil that’s AP4 rated and higher quality. The numbers of the oil are only 1/2 the problem. The amount of oil and the engine itself is part of it. In general you change for the filters not the oils on these. Head to Bobistheoilguy forum
I do oil changes at 15k. 6-7 is too low for a pure synthetic. I also switched to the Ford F-150 diesels oil that’s AP4 rated and higher quality. The numbers of the oil are only 1/2 the problem. The amount of oil and the engine itself is part of it. In general you change for the filters not the oils on these. Head to Bobistheoilguy forum
Running long OCI's with the wrong oil can be detrimental to the life of your motor. Have you analyzed your oil at those 15k intervals? I'd be curious as to what your TBN was and how much diesel you may have diluted in the oil. If you stick to the STJLR.03.5005 spec, that TBN is likely far too low to get you safely out to those intervals. SA is the PM that remains as the result of engine oil combustion, and this is what fills up your DPF. SA is mostly derived from the oil's anti-wear and detergent additives. TBN basically measures the amount of additives left in your oil, and that is why in this spec oil the TBN is as low to begin with as it is, because of the spec mandate for a low SA content.
Changing the oil filter isn't going to get rid of the diluted diesel in your oil, you're going to have to change the oil for that.
The Ford manual says you should run FA-4 5w-30 or CK-4 5w-40 in their 3.0L diesel F150, but both of those oils have a SA content of ≤1.0, and the F150 has an entirely different EGR and SCR/ DPF. I haven't ruled out using a BMW LL-04 or MB229.52 spec oil, but everything else is essentially a "mid-SAPS" oil with a SA ≤.08 and given how particular the oil dilution issue can be, I'm not sure I want to tempt fate and the warranty by running an oil with a greater SA content than what STJLR.03.5005 calls for. Not my favorite oil spec, no doubt, but motor oil is a lot less expensive than a new motor.
I live in Houston and do mostly short hops. That’s all pure nonsense. If anything it’s better. I average better city than I do Highway (I drive fast). Turn off the auto start/stop when you throw it in gear.
I should have clarified. Lots of short trips with cold starts, which is not great for diesels with DEF as it doesn't heat up properly and no time to regen to clear the DPF. Even if the engine is warm, Im not sold on lots of short trips with regen needs for the general health of the engine/system in the long run. The additional concern of oil dilution doesn't help. It has nothing to do with low end torque or fuel economy.
Running long OCI's with the wrong oil can be detrimental to the life of your motor. Have you analyzed your oil at those 15k intervals? If you stick to the STJLR.03.5005 spec, that TBN is likely far too low to get you safely out to those intervals. SA is the PM that remains as the result of engine oil combustion; mostly derived from the oil's anti-wear and detergent additives. TBN basically measures the amount of additives left in your oil, and that is why the TBN is as low as it is in this spec oil - it calls for a low SA content.
Changing the oil filter isn't going to get rid of the diluted diesel in your oil, you're going to have to change the oil for that.
The Ford manual says you should run FA-4 5w-30 or CK-4 5w-40 in their 3.0L diesel F150, but both of those oils have a SA content of ≤1.0, and the F150 has an entirely different EGR and SCR/ DPF. I haven't ruled out using a BMW LL-04 or MB229.52 spec oil, but everything else is essentially a "mid-SAPS" oil with a SA ≤.08 and given how particular the oil dillution issue can be, I'm not sure I want to tempt fate and the warranty by running an oil with a greater SA content than what STJLR.03.5005 calls for. Not my favorite oil spec, no doubt, but motor oil is a lot less expensive than a new motor.
The new spec for oil meets and exceeds all the STJLR.03.5005 requirements. CK-4 is a different story. 1st-oil will only void a warranty if the failure is determined to have been a direct result of the oil used which falls on the company to prove. 2nd-if there’s fuel in the oil then then dilution has taken place which changes spec of oil and would make a failure due to lubrication still the fault of the manufacturer. 3rd-the engines are very similar and not sure what the EGR/DPF/Regen has to really do with oil. The F150 uses the same engine which ran on the same spec of oil. The new AP4 is a new spec they spent a few years working on specifically for this engine. That oil is better. The STJLR.03.5005 spec is a recommendation and not a requirement. You may use any oil that meets or exceeds that spec. The AP4 exceeds the spec I don’t believe the BMW oils are considered comparable. Before making the switch I did digging and found documentation linking the STJLR spec to other specs and the AP4 exceeding that. I don’t recall ever seeing BMW on there or I’d have considered it. I drive my engine hard regularly, which is good for it, and it doesn’t make oil. I’m about to change mine at 10k because I spent 1k towing a 7500lb boat and will be getting it tested. I will say that I was able to tell my engine was happier (smoother and quieter) on the AP4
The new spec for oil meets and exceeds all the STJLR.03.5005 requirements. CK-4 is a different story. 1st-oil will only void a warranty if the failure is determined to have been a direct result of the oil used which falls on the company to prove. 2nd-if there’s fuel in the oil then then dilution has taken place which changes spec of oil and would make a failure due to lubrication still the fault of the manufacturer. 3rd-the engines are very similar and not sure what the EGR/DPF/Regen has to really do with oil. The F150 uses the same engine which ran on the same spec of oil. The new AP4 is a new spec they spent a few years working on specifically for this engine. That oil is better. The STJLR.03.5005 spec is a recommendation and not a requirement. You may use any oil that meets or exceeds that spec. The AP4 exceeds the spec I don’t believe the BMW oils are considered comparable. Before making the switch I did digging and found documentation linking the STJLR spec to other specs and the AP4 exceeding that. I don’t recall ever seeing BMW on there or I’d have considered it. I drive my engine hard regularly, which is good for it, and it doesn’t make oil. I’m about to change mine at 10k because I spent 1k towing a 7500lb boat and will be getting it tested. I will say that I was able to tell my engine was happier (smoother and quieter) on the AP4
You are referring to the Magnusson-Moss Warranty Act here in the US. Theoretically, you are correct, but the dealer can still deny your claim if they don't like your maintenance records, and force you to litigate in order to make them move. The same thing with regard to the fuel dilution, although with the known dilution issue on the JLR diesels, it would be all the more so difficult for JLR to try and disavow liability if you had such a failure. Of course, if you're out of warranty, you don't want to be relying on your dealer, anyways. Me personally, I'm more concerned with keeping my motor in tip-top shape (I'll do my own oil and fluids, brake pads, etc.), and less concerned with dealer/warranty issues. As for the EGR, does the F150 running a similar EGR as the Discover V? Ex. does it use same low-pressure EGR as LR that draws back filtered/treated exhaust rather than raw, untreated diesel exhaust? Drawing back untreated raw diesel exhaust and dumping it into the EGR is a great way to plug it up with PM real quick.
Instead of AP4, I believe you are referring to FA-4? Actually, it's very similar to the CK-4 but intended for 5w-30 viscosity with a lower HTHS, (for fuel economy.) Lubrizol has a nice comparison tool. Simply put, there are better (more stringent) oil specs out there for our light-duty diesels. BMW LL-04, dexos2, MB 229.52, or VW 505.01. You are right on the JLR spec, it reads as only to be a suggestion. Below is from JLR where they do say that you can use an ACEA C2, and that might be what I do in order to ensure that I maintain coverage under the initial warranty period. Motul has an 8100 X-clean EFE 5w-30 that I can get a 5L jug on Amazon for $42.50. I would probably prefer a 5w-40 to help protect the bearings, and it's 12.1 cSt viscosity at 100ºC is nearly a 5w-40 to begin with, has a good HTHS at 3.5, decent TBN at 7.7, and is considered a mid-SAPS with SA at .78.
This is another reason I may want to wait for a MY21 Discovery. GM and BMW are also expanding their embedded infotainment systems for MY21, by adding Android Auto as a base for their systems. The JLR product is ripe for the addition of a wireless Android Auto/Apple Carplay, not to mention probably a boost in the H/W components. I would wager that the system in the new Defender will likely make it's way across the lineup.
FCA has a new generation of its Uconnect coming out soon. Wireless Apple Carplay and Android Auto is huge (Google Maps is simply the best and really negates the need for a navigation mapset.) CPU is six times as powerful as the current system; 6GB RAM, 15 million pixels, nearly twice the resolution of a 4k TV.
Fiat Chrysler's next-generation Uconnect is faster, built on Android
You’re right on the FA-4 not AP 4. I keep getting it mixed up in a correlation to something entirely else (the Jet I fly). The FA-4 is the newest spec that just started really becoming available in my area around August. There may be better oils depending on what metrics are being looked at but Ford designed this oil specifically due to the 3.0 lion diesel engine. Another oil might be great but for completely different reasons that are not specific to the design of this motor. She’ll Rotella is a good example after the recommendations were eventually changed to run it in the Ecodiesels. As far as I know there’s no higher quality spec for this engine than FA4 . CK-4 is designated for your larger heavy Diesel engines. CK is backwards compatible but the FA isn’t. Don’t want to run it in the bigger motors. The older engines need the higher HTHSV than new engines. You mention there being more stringent specs out there but in what way? Everything I’ve read based on the specs of FA-4 state it’s the most stringent and newest spec out there where Ford will require oils that meet the CK/FA4 spec to be used in all diesels moving forward.
You’re right on the FA-4 not AP 4. I keep getting it mixed up in a correlation to something entirely else (the Jet I fly). The FA-4 is the newest spec that just started really becoming available in my area around August. There may be better oils depending on what metrics are being looked at but Ford designed this oil specifically due to the 3.0 lion diesel engine. Another oil might be great but for completely different reasons that are not specific to the design of this motor. She’ll Rotella is a good example after the recommendations were eventually changed to run it in the Ecodiesels. As far as I know there’s no higher quality spec for this engine than FA4 . CK-4 is designated for your larger heavy Diesel engines. CK is backwards compatible but the FA isn’t. Don’t want to run it in the bigger motors. The older engines need the higher HTHSV than new engines. You mention there being more stringent specs out there but in what way? Everything I’ve read based on the specs of FA-4 state it’s the most stringent and newest spec out there where Ford will require oils that meet the CK/FA4 spec to be used in all diesels moving forward.
I don't think Ford really had anything to do with FA-4, and Ford was building Lion V6 diesel motors long before API came out with it. The main requirements to FA-4 are identical to CK-4 save for a lower viscosity (5w-30) and it's lower HTHS, purely for fuel economy. Theoretically, they are both heavy-duty diesel specs, intended for heavy-duty diesel application and thereby are supposed to be high enough quality to not shear or oxidize. Noack ≤13 is awfully high, and we can get lower than ≤ 1.0 in SA.
There is some debate out there that these new lower HTHS oils can provide the same level of protection with less restriction, thereby theoretically offering slight gains in fuel economy. GM is adamant, for example, in my Yukon 6.2 that 0w-20 is the only oil viscosity to use, despite being the same long block that went into Corvette and Camaro that called for 5w-30, (and of which Corvette in 2019 subsequently changed from 5w-30 to 0w-40.) I'm skeptical but with Mobil1 Extended Performance oil, OCI's at about 7k miles, I've been running what they say. The same thing in my wife's Infiniti with the Nissan 5.6 V8, 0w-20; will probably do 5k mile OCI's in that. But the JLR spec already called for a low HTHS with fuel mileage in mind.
MB 229.52 is probably the most stringent spec out there. But once you get past the specs and into looking at the specs of each specific oil, that is what really matters. I believe there is a correlation where you can usually tell whether the base stock is premium (Group IV or GTL) or not based on the pour and flashpoints. -30 ºC and below and over 230 ºC usually means it's a good base stock, which tends to equate to a good resistance to shearing and low noack, or volatility. I think the Motul 8100 series noack are usually below 10%. (volatility; measures evaporation loss over a period of time at high temperature. Essentially means less oil vapors turning into carbon build-up.)
Either of these Motul spec oils are probably better than FA-4 anything, IMO. Lower SA content, lower noack, and a higher HTHS (depending upon what you're looking for). Honestly, I'm sure the FA-4 will be just fine, though. Whatever oil you use, get a UOA and see what it looks like. It's not going to tell you everything but it's better than nothing. If you want to try and run extended OCI's, add a TBN analysis and see if you can push it. With modern direct injection, turbochargers, and all the emission equipment on a modern diesel, coupled with the fact that excellent oil is readily available and inexpensive, I see no need to push my OCI's past 6k or 7k miles, but that's just me. Run a good oil, change it responsibly, and you should be fine.
01-23-2020, 10:24 AM
and even with charts and graphs . . . 
