The Ecoboost engine and the type of oil...

Aug 14, 2019
Disclaimer. I am just an average guy who has no degree or experience in chemical engineering. Several months back one of my trucks...a 2018 Lincoln Navigator which has a similar drivetrain to the Ford F150 and the Ford Raptor...developed a cold start rattle and started sounding like a diesel. I took it into the dealership as it was under warranty and didnt get the truck back for over a month. When I did get it back I had to take it in for a 2nd time and then it was another 3 or so weeks. It was nightmarish and thus I started out on an online quest of sorts. During that quest I was banned from the F150 Forum because I had suggested their F150 was faulty. I never said that. I simply wanted to figure out what went wrong and how it could be prevented. I really like the truck, but all this going wrong made me wonder and thus investigate further.

The most useful post so far on the Ecoboost issues is this one by "RONAKA"

In that post he stated the following:

"The EcoBoost provides some unique challenges for the oil. First it is direct injection and that tends to promote blow-by the rings especially during startup. Second the PCV system becomes quite ineffective during boost conditions as there is no positive flow through the crankcase. The combination of these two factors is not good. The oil suffers from dilution and viscosity loss due to the gasoline, and the corrosion inhibitor (TBN) levels are consumed more rapidly due to poorly vented moisture.

What does that mean when choosing oil? I would suggest the following in order of priority:

1. Get the highest possible 100 deg. C viscosity SAE 30 weight oil. SAE 30 viscosity is within spec from 9.3 to 12.5 cSt. You want an oil as close as possible to the 12.5 cSt. The purpose is to keep the viscosity in the SAE 30 range, even after gasoline dilution. The higher the starting viscosity the better.
2. A secondary measure of high temperature viscosity is HTHS. Again you want as high a value as is available for a SAE 30 weight oil. Oils meeting ACEA E6, E7, & E9 will have a minimum HTHS of 3.5.
3. A high TBN value is useful to prevent corrosion due to moisture in the oil, and extend life of the oil. An oil meeting those ACEA specs will have a minimum TBN of 9.

Assuming your want to maintain your Ford warranty, you will have to choose a 5W-30 oil, that meets Ford specs or is API SN qualified. Note that Fords does not say it has to be GF-5 qualified, and it is actually best to avoid oil which is GF-5 qualified. It has a fuel economy component which discourages higher viscosity oil, which is your number 1 priority.

So what oil? I suggest one of the three following oils. The first two are potentially the same oil with different names, and both good.

1. Mobil Delvac 1 LE 5W-30 - It is API SN qualified, has a 100 deg. C viscosity of 11.8, HTHS >3.5, and TBN of 10.

2. Chevron Delo 400 LE Synthetic 5W-30 - Also API SN qualified, 100 deg. C viscosity of 11.7, HTHS > 3.5, and TBN of 9.8.

3. Kendall GT-1 Full Synthetic Euro 5W-30 - API SN qualified, 100 deg. C viscosity of 12.0, HTHS 3.5, and TBN of 7.3. This one is a bit of a mixed bag, and the reason I put it third. It has the highest 100 deg. C viscosity, but the lowest TBN... Probably good if you are not going to attempt long oil change intervals, which I would not recommend in any case."

"RONAKA"s post was the absolutely most helpful and that is the route I took. Today I use Mobil 1 Delvac 5W40 when the temperature is over 60 Spring/Summer and 5W30 when the temperature is below 60 Fall/Winter. Why the switch during the winter? I found out by looking at countless oil analysis that many 0W40 and 5W40 reports show a lot of iron wear during the winter. The reason is simply because its a bit harder for the engine to warm up the 5W40 thicker oil type and thus the engine runs rich until its at operating temperature. Running rich, of course, stresses the engine more and thus you have more iron wear.

Mobil 1 Delvac is Amsoil like in that its Group IV PAO based. Its a high quality oil. Delvac is designed for turbo diesel engines which have the same problems as Ecoboost engines such as fuel dilution. Delvac will resist that dilution thus its an ideal oil for the Ecoboost engine. Keep in mind its also rated API SN so its a dual use oil.

For operating in conditions over 60 degrees most especially Arizona style environments, doing a lot of towing or hauling, very spirited driving and high pressure turbos there is no question in my mind that 5W40 is the way you want to go. Ive done the oil analysis and both Delvac and Mobil 1 Turbo Diesel Truck 5W40 are overall better in every they are not hard on the wallet. There is no question that boutique oils like Amsoil and Redline are superior to Walmart shelf oils, but they are expensive and not available on the Walmart shelf.

However, in colder environments you certainly want something thinner for faster warmup so the engine isnt constantly running rich. If its freezing outside you not concerned about the engine overheating thus I suggest Mobil Delvac 5W30.

So in conclusion my suggestion for Ecoboost owners is Mobil 1 Delvac for over 60 degrees outside and 5W30 for under 60 degrees. Of course special situations like lots of towing will call for 5W40 too.

About that warranty...yes using an oil not specified in the owners manual will void that warranty, but no one at the 3 dealerships Ive been to asked me about what oil I put in there and, of course, you can always lie...tell them you put in that Motorcraft 5W30, but no one asked me about my oil changing habits at all. I just have this to say in that regard. I followed the owners manual religiously and guess what? It resulted in my truck being a fixture and pet project at the dealerships service department for nearly 2 months. When I got the truck back seemed like they banged the door and had it fixed along with a few other scratches. Thus Im looking for my own answers to these problems.

Another issue I had with the truck was the 10R80 failing at 74000 miles. I found out when you start to feel the hard shifts around 25-30k miles is when you get the transmission flushed by the dealership. That will help with the transmission longevity.

I am open for debate. Keep in mind...I am just an average Joe who enjoys Ford products, but need answers and action on these critical issues.

Keywords for Google searches: Ford F150, Ford Raptor, Cold Start Rattle, Cam Phasers, CamPhasers, Lincoln Navigator, Ford Expedition, 10R80, Transmission, 10 speed, 2nd Generation Ecoboost, 2nd gen ecoboost, fuel dilution
Originally Posted by Navi
Today I use Mobil 1 Delvac 5W40 when the temperature is over 60 Spring/Summer and 5W30 when the temperature is below 60 Fall/Winter. Why the switch during the winter? I found out by looking at countless oil analysis that many 0W40 and 5W40 reports show a lot of iron wear during the winter. The reason is simply because its a bit harder for the engine to warm up the 5W40 thicker oil type and thus the engine runs rich until its at operating temperature. Running rich, of course, stresses the engine more and thus you have more iron wear.

Cool story bro, but really, where did you come up with that about the engine taking longer to warm up with the thicker oil? Time to warm up is dependant on the cooling system much more than on the oiling system.
I think that you (actually Navi) may have a good point, but I seriously doubt that Mobil Delvac and Chevron Delo are the same oil.....two totally different companies.
I use my Navigator for work and since March 2018 I have put 98000 miles on it. I drive it daily. So I know exactly how it should warm up and what temperature it should be hitting. I switched to the 5W40 after I got the truck back from the dealer over the summer and its been GREAT. Runs really smoothly on the 5W40. When I say it runs GREAT it just seems to be a lot more refined then when I ran it with Valvoline 5W30. The Valvoline is great oil for most vehicles, but not for this fuel diluting biturbo 450 horsepower beast. When they formulated the regular standard synthetic oil they didnt think the engine would be diluting the oil with lots of fuel.

Now that its colder it really takes a while for the engine to heat up with 5W40. I did some research and friction is to blame. Less friction with 5W40 and of course its a bit thicker. Over the summer the engine seemed to run cooler which was desired but running too cool can cause problems.

I dont have any ability to conduct scientific analysis on the colder weather issue, but I know 100% it didnt take this long to heat up to operating temperature using 5W30...
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One thing which I thought about just now is the thermostat came with the truck. In the past I did have some issues with thermostats going bad on different vehicles. Thus Im going to order a thermostat, change that and see if it effects the warmup. The thermostat could be stuck open...of course if this is the case it would change my post.
I choose 10W-30 M1 for my 2 EB trucks. No issues what so ever, even at 100,000 miles. I change every 5000.

I do agree with the post quote above and could have written that myself. Oil viscosity and oil cleanliness is of prime importance in EB engines. I'm not 100% convinced on the need for super high HTHS, as EB engines maintain good oil temperature control and don't typically operate in the range where HTHS viscosity comes into play. HOWEVER, oil with higher HTHS is often more robust and will maintain viscosity properly over a wide range of conditions.

In years past, a 10W-30 oil would be more shear resistant and therefore a better choice in EB engines, despite initial new oil specifications. Once fuel dilution comes into play, remaining viscosity is very important. It's my belief that higher is better. The 5W-40 choice is superb in many conditions.
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Mobil 1 AP is as good as Amsoil and Redline and in some instances, better.
Originally Posted by buster
Mobil 1 AP is as good as Amsoil and Redline and in some instances, better.

Now you've done it BITOG Boutique oil Blasphemy.
The other way to go about this with Ecoboost engines is to change the oil sooner than the 10,000 mile interval suggested by the oil percent gauge. Previous to my camphaser/chain problems I was changing it at 7000 miles with Valvoline Maxlife Full Synthetic. However, if you change it at 7000 miles it will probably be diluted into 5W20 territory by then. So for a cleaner oil and a less diluted oil its probably best to change before 5000 miles. So with the Valvoline full synthetic probably would have been ideal to change at 4000 miles or so.

However, I took the Delvac route. Felt it was best to use an oil that was designed for fuel dilution and that would run cleaner. The deal I got at Summit Racing was about the same I would pay for full synthetic at Walmart. Also, Delvac is more like boutique oil being made with PAO. My personal feelings and observation is the engine seems to like it. Runs real smooth and quiet.
Originally Posted by dlundblad
Would there be any issues running a 0w40 such as Mobil 1?

In my 2015 … M1 0w40 is what I ran for the last 20k after doing all the noise testing … (5k OCI, 2x on filter)
(tested PUP & M1 in 5w30 and M1 Formula M in 5w40)
The engine ran quieter on the 40's …

I was probably pushing it on calcium … but the engine loved mid grade gasoline and ran great.
The 5w-40 will warm up faster than 5w-30 due to hydrodynamic oil friction in the bearings which is what heats engine oil. Your vehicle is taking linger to warm up, now that it's colder, because you are starting the warm up phase at a lower ambient temperature.
A 2018 with nearly 100,000 miles? With the problems that you've had, I would trade that rascal in a hurry. My guess is that you got a lemon. The problems you are having is not representative of the entire line of Ford products equipped like your Navigator. If you wish to continue driving it, the 5w40 Delvac is a good choice. 5W30s on the thicker side are good too. The thicker 5W30s are Mobil 1 original, QSUD and Havoline Pro DS.
He drives a livery service in NYC. I think the vehicle is holding up fine but it might be approaching end-of-life in that environment.
The 5w40 is likely to be Mobil Delvac 1 ESP whereas the TDT is an M1 product line targeting the main 3 LT's
Also, I don't think you need a 500hp Ecoboost delivery vehicle in NYC. Something more robust and economicaly designed for that type of service. The Ecoboost is a high-strung and maintenance hungry engine for that environment.
Is this the 3.5 Ecoboost you're talking about? I have a 2.7 that's fairly new to me and wonder if all this applies to this motor too? I'm currently using Havoline Pro DS but have wondered if a 40w might be more appropriate given possible fuel dilution. I plan on getting a UAO at 5000 miles on the Havoline to see how it held up.
I'd use an HTHS 3.5 (or close to that) oil in an Ecoboost. Ford says they want HTHS 2.9-3.2, and a little extra is good with fuel dilution.

My choice would be Mobil1 ESP 5w30 or ESP 0w30 or ESP 0w40 (Corvette oil, not the 229.5 high saps one). Some autoparts store have those.

They shouldn't leave as much deposits on the valve stems, and are compatible with 2019+ current low-sulfur gasoline.
I only know about the engine which I have and that is the 3.5 liter 2nd generation Ecoboost and what I know is it has problems with camphasers and chain stretch. Ive done a lot of internet research and these same problems cropped up in the 2017 F150 much sooner. Mine occurred at 94000 miles.

Oil is pretty cheap and the truck is expensive. So my suggestion whether it be the 3.5 or the 2.7 liter is to complete the oil change before 5000 miles and do full synthetic. There is tendency to believe the maintenance guide and I think its wrong to do it at 10000 miles. Also the 10R80 should be flushed at 30000 miles.

I was looking at the Ford Tech on Youtube who went through a transmission thoroughly stating the solenoids get contaminated and caused bad shifts. He said to change trans fluid every 30000 miles. Thats what I did recently and the bad shifts were gone. On my first 10R80 I was told by the dealer to change the fluid at 100k miles. I went by that and the transmission failed at 74000 miles.

For just about any car you are best waiting until the 4th model year so they can get out the problems. Besides the engine and the trans there hasnt been any problems, but those are huge problems at that...
Ford's owners manuals can cause problems too … I had 150k service … but digging around in a completely different part of the manual severe service was 30k …
heck of a mileage spread even if you have negative views on "severe service"