15W-40 in 2019 V10

[HighDesert]

Just had my MH serviced today and once I got home, and read over all the invoice, I noticed that it stated 15w-40 oil used as opposed to 5-20 or 5-30. Should I be concerned or is the only difference I’m going to see is lower mpg due to higher viscosity? I know Ford specs 5/20 or 5-30......,just trying to decide if I need to go back and make a bunch of noise to replace the oil, or not.

[jacwjames]

I would take it back


I forgot that my Jeep 5.7 Hemi was suppose to use 5W20 and instead put 5W30. My check engine light came on, took it to Autozone and they ran the code, my oil sensor failed and I ended up replacing and changing the oil. Far as I know it didn't hurt the engine for the short time the 5W30 was in.

[Earl II]

Originally Posted by HighDesert

Just had my MH serviced today and once I got home, and read over all the invoice, I noticed that it stated 15w-40 oil used as opposed to 5-20 or 5-30. Should I be concerned or is the only difference I’m going to see is lower mpg due to higher viscosity? I know Ford specs 5/20 or 5-30......,just trying to decide if I need to go back and make a bunch of noise to replace the oil, or not.

15-40 oil is usually for old Volvos or some diesel engines and Onan generators. Not putting in what is noted on the oil filler cap is just weird, dumb.

[Ray,IN]

Originally Posted by HighDesert

Just had my MH serviced today and once I got home, and read over all the invoice, I noticed that it stated 15w-40 oil used as opposed to 5-20 or 5-30. Should I be concerned or is the only difference I’m going to see is lower mpg due to higher viscosity? I know Ford specs 5/20 or 5-30......,just trying to decide if I need to go back and make a bunch of noise to replace the oil, or not.

Have the correct oil installed, don't forget the filter has the heavy oil in it too.
If the engine is under warranty, 15W40 may invalidate any warranty claims in the future.

[twinboat]

Before you go thru any oil and filter changes, look at the oil specs for the engine. The oil in it may be on the list.

[lllkrob]

As a former powertrain systems engineer, the 15w-40 will not hurt your engine or make a measurable difference in your fuel mileage. The only reason FORD uses 5w-20 oil is to help meet CAFE corporate standards.

[EyezOpen]

Originally Posted by lllkrob

As a former powertrain systems engineer, the 15w-40 will not hurt your engine or make a measurable difference in your fuel mileage. The only reason FORD uses 5w-20 oil is to help meet CAFE corporate standards.

In total agreement,15/40 would provide more consistent lubrication and cooling in a high stress/heat scenario.

[stew1]

Have used 10w40 for years we live in very hot climate

[robertkathy]

having a father that for many years was in with the api (he ran an oil company) and being in az the oil i run in my class a is the same as the oil i run in my mini cooper and my harley shell rotella t6 15w40.

15W40 means that at cold temperatures the oil has the same viscosity as SAE 15W oil. At high temperatures it has the same viscosity as SAE 40 oil.

The Society of Automotive Engineers or SAE has established an arbitrary scale for the viscosity of motor oils. The scale ranges from 0 to 60.

The numbers from 0 to 25 have the letter W added. This means that they are "winter" viscosity, for use at lower temperatures.

The viscosity of a liquid is its resistance to flow. High intermolecular forces between the molecules cause a high viscosity.

As the liquid warms up, the added kinetic energy overcomes some of the attractive forces. The viscosity decreases. Hot molasses flows more readily than cold molasses.

A single grade oil like 15W or SAE 40 oil has a high viscosity when cold and a lower viscosity when hot. The first number 15W is the viscosity of the oil at cold temperature, and the second number 40 is the viscosity at 100 °C.

The 15W40 designation means that the oil is a multigrade oil. It has the viscosity of 15W when cold and the viscosity of SAE 40 when hot. This means that one type of oil works in all temperatures.

[HighDesert]

After reading comments, I went back to my service guy who changed out the oil and filter and only charged difference in cost per quart. We both agreed that we should have stated oil type requiring at service write up. My assumption was service person would put in what was on oil cap. Problem solved. Thanks for responses back.

[RELHUB]

Originally Posted by HighDesert

Just had my MH serviced today and once I got home, and read over all the invoice, I noticed that it stated 15w-40 oil used as opposed to 5-20 or 5-30. Should I be concerned or is the only difference I’m going to see is lower mpg due to higher viscosity? I know Ford specs 5/20 or 5-30......,just trying to decide if I need to go back and make a bunch of noise to replace the oil, or not.

MAKE a LOT od noise that could cause big problems
especial in cold weather.

I am sure they are going to tell you it was a typo and claim they used the correct grade oil. Do not accept that answer insist they do another oil change ASAP

[RELHUB]

Originally Posted by HighDesert

After reading comments, I went back to my service guy who changed out the oil and filter and only charged difference in cost per quart. We both agreed that we should have stated oil type requiring at service write up. My assumption was service person would put in what was on oil cap. Problem solved. Thanks for responses back.

I don't go to my Accountant and then tell him how to do my taxes.
TELL them that is BS they are a oil change shop.
They are responsible to use the correct grade oil.

[HighDesert]

Originally Posted by HighDesert

After reading comments, I went back to my service guy who changed out the oil and filter and only charged difference in cost per quart. We both agreed that we should have stated oil type requiring at service write up. My assumption was service person would put in what was on oil cap. Problem solved. Thanks for responses back.

Guess I wasn't clear in my post - the shop drained the 15 - 40 and put in the right oil and new filter. I was only charged the different in price per quart.

[F4Gary]

Originally Posted by RELHUB

I don't go to my Accountant and then tell him how to do my taxes.
TELL them that is BS they are a oil change shop.
They are responsible to use the correct grade oil.

Reread post #10.