I am using Shell Rotella 5w-40 T6 oil

C

carguy75

Member
Location
alpharetta,ga
Yesterday I began using Shell Rotella 5w-40 T6 motor oil in my FX45. I made this decision because my FX seems to loose about a quart or two of oil between oil changes. So I did some research about the older VK45DE oil consumption in the older pre-2006 M45 and Q45 forums because they have the same engine as the older pre-2006 FX45. I found out that the older VK engines burn oil no matter what car it is installed in. I believe that the older VK engine has piston rings that are not controlling the oil well, and let oil and gases slip past the pistons and into the combustion chamber. In addition, since the pistons are not seating properly, the heat from the pistons are not being transferred to the cylinder walls and causes the oil to burnoff and leave deposits due to the piston's extreme heat, especially regular oil. Which in time causes the rings to stick more and the problem gets worst until the VK began to smokes all the time. Also the oil from the piston blowby will pool inside the intake manifold and valve covers which would clog up the PCV system, especially with regular oil. Using synthetic oil helps due to it resisting burn off, however the oil can still get past the pistons and into the intake manifold, especially when using the lighter 5w-30 weight oil which shears down to a 5w-20 weight in about 2k miles of use. Therefore, I am trying the 5w-40 weight because it is thicker than the 5w-30, but thinner than the 10w-40 that is recommended to be used in the FSM when the FX is used in hotter climates. Therefore, I am hoping that the thicker 5w-40 oil weight will not slip past the piston rings like the 5w-30. In addition, Shell Rotella T6 oil seems to be a good oil that resist burn-off and can handle high temperture use without shearing since it mostly see turbo diesel use in trucks and high reving sport bike owners seem to like Shell Rotell 5w-40 also, as well as the germany car guys due to Shell Rotella T-6 5w-40 having a BMW longlife oil certification . So, I am trying it out. So far, my FX likes the oil. My FX started up fine this very cold morning and the engine seems very responsive. So, will I see if my FX still loses oil with the 5w-40 after a couple months of driving compared with using the 5w-30. For FX45 owners that has oil consumption problems, using 5w-40 maybe a solution. I will give some feedback in about 60 days about the oil consumption or hopefully lack of oil consumption.
 
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I use T6 in my M45 Plus you can order it online and pick it up at walmart in 4 gallon jugs.
 
I like it and have been using it for over a year without any ill effects. I honestly did notice the M ran smoother after I made the switch.
 
Hey fxlr8. I have to agree with you about the T6 making the VK run smoother. I notice that my FX45 have been running smoother for the last couple days since the oil change. I thought that I was just imaging it,however since you noticed the same smoothness in your VK engine after the switch then maybe the VK really likes the T6 oil or the 5w-40 weight or both. P.S. I have also noticed that my MPG's are still the same, no more no less. However, it is still too early for me to state that as a fact just yet.

---------- Post added at 07:11 PM ---------- Previous post was at 07:04 PM ----------

Oreilly Auto Parts sells the Shell T6 four quart jugs for $19.00. For the time being Oreilly will be where I will buy my T6 oil.
 
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carguy75 said:
Hey fxlr8. I have to agree with you about the T6 making the VK run smoother. I notice that my FX45 have been running smoother for the last couple days since the oil change. I thought that I was just imaging it,however since you noticed the same smoothness in your VK engine after the switch then maybe the VK really likes the T6 oil or the 5w-40 weight or both. P.S. I have also noticed that my MPG's are still the same, no more no less. However, it is still too early for me to state that as a fact just yet.



---------- Post added at 07:11 PM ---------- Previous post was at 07:04 PM ----------

Oreilly Auto Parts sells the Shell T6 four quart jugs for $19.00. For the time being Oreilly will be where I will buy my T6 oil.
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Hey man... Dont know if you read my thread recently, but I have 55k and was losing a little over a quart per 3k. Now I notice is mostly when I make a high speed run (couple trips to DC at 90mph) and absolutely no smoke. Dealer tried to go right at the valve covers. My local guy explained the PCV design of the valve cover internals and it sounded likely, as well as the oil rings fouling. So I used a detergeant additive and at the next change I plan to switch to synthetic since this is exactly what he recomended. I seafoamed the hell out of the inside of the valve covers and replaced the PCV valves on both sides. If this doesnt work I will replace the valve covers myself. We need to both keep at this and try to determine what works since I know there are other people here who have this same problem. I was going to use mobil 1 since my other car takes it but might try the shell like you.
 
Hi 1yakini. It seems like we have the same problem with oil consumption. I believe that our FXs need a heavier weight of oil like 5w-40 because we have piston rings that are not too tight and let the lighter weight oil past the pistons which clog up the PCV and valve covers channels. I have been using the T6 for about a week and have to say that performance and gas mileage is good. I did not lose any MPG due to the switch and the FX pulls like a beast. Fact: our variable valve timing system is oil pressure dependant so I believe that the 5w-40 weight is keeping the oil pressure in the green and the VVTC system is running like a charm. Even if the engine consume oil after my 60 day test, I will probably keep using the 5w-40 weight due to how smooth and responsive the engine runs and how cheap the T6 oil is to buy. I believe the FX45 should have had the 5w-40 oil weight from the beginning. I guess Infintii use the 5w-30 conventional oil to save money and to boost MPG numbers compared to them using an thicker 10w-30 or 10w-40 conventional oil in the FX45. P.S. I drive my FX hard also, which may be a factor in why I was burning off my old 5w-30 oil, especially in the very hot summers here in Ga.
 
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carguy75 said:
Hi 1yakini. It seems like we have the same problem with oil consumption. I believe that our FXs need a heavier weight of oil like 5w-40 because we have piston rings that are not too tight and let the lighter weight oil past the pistons which clog up the PCV and valve covers channels. I have been using the T6 for about a week and have to say that performance and gas mileage is good. I did not lose any MPG due to the switch and the FX pulls like a beast. Fact: our variable valve timing system is oil pressure dependant so I believe that the 5w-40 weight is keeping the oil pressure in the green and the VVTC system is running like a charm. Even if the engine consume oil after my 60 day test, I will probably keep using the 5w-40 weight due to how smooth and responsive the engine runs and how cheap the T6 oil is to buy. I believe the FX45 should have had the 5w-40 oil weight from the beginning. I guess Infintii use the 5w-30 conventional oil to save money and to boost MPG numbers compared to them using an thicker 10w-30 or 10w-40 conventional oil in the FX45. P.S. I drive my FX hard also, which may be a factor in why I was burning off my old 5w-30 oil, especially in the very hot summers here in Ga.
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There are a number of possibilities. There are pictures a guy took of a teardown which showed the bottom half of the pistons being very fouled which was in effect preventing the oil rings from free floating. This was a hi mile vk but using conventional oil apparently can definitely lead to sludge and other build up in the engine. There is alos the PCV possibility that we were talking about. Third there is also the theory that nissan used cheap rings or substituted tolerances for low friction hi revving rings which allow lots of blow-by by design. Thats whats making this difficult as no one knows for sure what the issue is. I will say that my last oil change burnt from the H to below the L in 3k miles, but that I took a few trips to DC at high speeds... so 90 minutes at 90-100 mph with another 60minutes at 85 plus each trip. The consumption was noticable at these speeds. Since this last change I have used the detergent additive in the oil and stayed at legal speeds and I apparently have 0 consumption after 1k miles. It it obvious of course that a car will burn more oil at high rpms especially at sustained distances just from the speed of the pistons. A faulty PCV system would no doubt make this worse. I am thinking now that there may be nothing wrong in my engine at this point. nevertheless, to head off any future problems I am still switching to synthetics and changing the PCV valves. If I encounter any further issues I will change the valve covers next. If I still have a problem at that point I will consider it an internal issue and move on to somethign else. Keep in mind I only have 55k on my car.

If you find the higher weight helps it could be that the tolerances are loose in that motor and the extra weight is preventing excess from burning up in the cylinders. The synthetic is also a high detergent oil and should help to remove any sludge that may have frozen the oil rings or clogged the PCV system. From what I remember on the teardown the top end of the car looked clean as a whistle, he didnt know there was an issue until he took out the pistons.

At the end of the day all motors consume oil, most people just dont check between oil changes and nobody hardly measures what comes out when they change it. Im just being extra cautious because I dont want to ignore something that leads to the FX being a smoker down the road. Good luck with yours and I will keep you updated on mines.

Found this and even though it is an old report it talks about most of these concerns. Especially about the high rpm driving.... " a car can burn up to 7 times the amount of oil at 70mph than 40mph". Good stuff.
http://www.le-international.com/uploads/documents/049_Notes on Oil Consumption.pdf
 
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1yakini said:
There are a number of possibilities. There are pictures a guy took of a teardown which showed the bottom half of the pistons being very fouled which was in effect preventing the oil rings from free floating. This was a hi mile vk but using conventional oil apparently can definitely lead to sludge and other build up in the engine. There is alos the PCV possibility that we were talking about. Third there is also the theory that nissan used cheap rings or substituted tolerances for low friction hi revving rings which allow lots of blow-by by design. Thats whats making this difficult as no one knows for sure what the issue is. I will say that my last oil change burnt from the H to below the L in 3k miles, but that I took a few trips to DC at high speeds... so 90 minutes at 90-100 mph with another 60minutes at 85 plus each trip. The consumption was noticable at these speeds. Since this last change I have used the detergent additive in the oil and stayed at legal speeds and I apparently have 0 consumption after 1k miles. It it obvious of course that a car will burn more oil at high rpms especially at sustained distances just from the speed of the pistons. A faulty PCV system would no doubt make this worse. I am thinking now that there may be nothing wrong in my engine at this point. nevertheless, to head off any future problems I am still switching to synthetics and changing the PCV valves. If I encounter any further issues I will change the valve covers next. If I still have a problem at that point I will consider it an internal issue and move on to somethign else. Keep in mind I only have 55k on my car.

If you find the higher weight helps it could be that the tolerances are loose in that motor and the extra weight is preventing excess from burning up in the cylinders. The synthetic is also a high detergent oil and should help to remove any sludge that may have frozen the oil rings or clogged the PCV system. From what I remember on the teardown the top end of the car looked clean as a whistle, he didnt know there was an issue until he took out the pistons.

At the end of the day all motors consume oil, most people just dont check between oil changes and nobody hardly measures what comes out when they change it. Im just being extra cautious because I dont want to ignore something that leads to the FX being a smoker down the road. Good luck with yours and I will keep you updated on mines.

Found this and even though it is an old report it talks about most of these concerns. Especially about the high rpm driving.... " a car can burn up to 7 times the amount of oil at 70mph than 40mph". Good stuff.
http://www.le-international.com/uploads/documents/049_Notes on Oil Consumption.pdf
Click to expand...

Interesting link you posted. According to the article I was right on the money about some of the causes of my oil consumption. However, I will not do any of the tests or a engine teardown unless the FX begans to smoke. It seems that 1 or 2 quarts of oil loss between oil changes is common especially if you drive fast according to the article. I do believe that my rings are the problem and will just use the 5w-40 weight oil and call it a day. I hope that the 5w-40 will reduce my oil loss to only one quart at the most in the summer and less than a quart in the winter. I can live with that. My old Mercedes E55 used to burn about a quart between oil changes as well, but according to Mercedes it required the 0w-40 and I believe it should be using an heavier weight oil as well. So I understand that high horsepower engines have a tendency to burn oil. I just never felt that the FX45 should be running only a 5w-30 non-synthetic oil because of the VK being such a high revving V8 engine. After reading the article's explanation about how cars that are driven faster burn more oil than slower driven cars, I am starting to think that maybe I should just start driving slower and maybe that will stop my oil consumption. However, I have too many low traffic back roads here that are fun to speed through with great curves.The roads are too much fun to stop using,unless the police started to crack down on them with more radar traps. So, I hope the T6 will let me have the best of both worlds-no oil consumption and a fast responsive engine that I can open up without worrying about my oil level.:good:
 
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I think you are right... One of the guys here has a bunch of posts on bosistheoilguy and his bump in weight along with a switch to mobile tdt gave him good results too. Im going to run regular mobile 1 at a 40 weight and see what that does before switching to tdt though. Good luck
 
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So after 2k miles around town I had no burn. This weekend I went up to Kings Dominion, so about 90 minutes each way. Now I am about a half quart low. This tranny sucks.... at 80 mph I am at 3k rpms and I tend to drive fast. So its consuming oil at 3k plus rpms for extended drives.... this makes sense. For comparison, my wifes cts-v is a 6spd and at 80 mph its humming along at 1900 on the tach. Based on that article I read and pragmatic thinking, it makes sense to say I am losing all my oil at those high extended rpms. Now the question is.... "is this a problem"? I dont think it is, I have a feeling that all cars will be guilty of this given circumstances. I had an intrepid that I drove cross country years ago and uknowingly ran it almost dry on oil since I was flying the whole 3 days of the drive. So in May I am still switching to Mobile 1 and we shall see.

Oh and a few hundred miles ago the oil was still fairly clean, after the extended drive it looks a lot blacker, maybe the high temps and that detergent additive have worked to clean out some of the build up.
 
Interesting find, keep us informed. I drive a lot of highway and I never noticed my rpms over 3K going that fast or faster, but I'll pay more attention now when I'm going 80. I currently run Mobil-1 and change at 7500 and the oil is black for sure at that point. I run Shell V-Power 95% of the time and the other 5% Mobil gas too.
 
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