Making the switch to 5W40 from 5W30

Joined
Jul 2, 2017
Messages
54
Location
Tennessee
Ive read some articles that say a high mileage engine could benefit going to 5W40 from 5W30. This is a modular 4.6L 1999 Grand Marquis. Non PI engine like the 96-98 Mustangs basically.

The car has 165K on it. The car didn't have the greatest oil change history from my mother's ownership of it. I just want to do what I can to make it last as long as it can anyway that I can lol.

I'm in a mild winter environment. We have alot of 35-55 degree days through the winter. There might be 7 days out of the year where temps will even drop below 20. Obviously freezing days happen every once in a while.

I have a local advance going out of business and can snag a gallon of a few different brands for just $20 on the 5W40

I
 
Ive read some articles that say a high mileage engine could benefit going to 5W40 from 5W30. This is a modular 4.6L 1999 Grand Marquis. Non PI engine like the 96-98 Mustangs basically.

The car has 165K on it. The car didn't have the greatest oil change history from my mother's ownership of it. I just want to do what I can to make it last as long as it can anyway that I can lol.

I'm in a mild winter environment. We have alot of 35-55 degree days through the winter. There might be 7 days out of the year where temps will even drop below 20. Obviously freezing days happen every once in a while.

I have a local advance going out of business and can snag a gallon of a few different brands for just $20 on the 5W40

I
You'll be fine. High mileage, or not.
 
Ive read some articles that say a high mileage engine could benefit going to 5W40 from 5W30. This is a modular 4.6L 1999 Grand Marquis. Non PI engine like the 96-98 Mustangs basically.

The car has 165K on it. The car didn't have the greatest oil change history from my mother's ownership of it. I just want to do what I can to make it last as long as it can anyway that I can lol.

I'm in a mild winter environment. We have alot of 35-55 degree days through the winter. There might be 7 days out of the year where temps will even drop below 20. Obviously freezing days happen every once in a while.

I have a local advance going out of business and can snag a gallon of a few different brands for just $20 on the 5W40

I
What benefit are the articles claiming? I have two vehicles with 370,000+ miles from new, and I just use the appropriate spec 5w-30 oils in each. BMW gets LL-01 or LL-04 and the Toyota just gets whatever 5w-30 synthetic is on sale at the moment.
 
The 4.6L modular engine will go many hundreds of thousands of miles with just about any oil. The engine is very well made.

A synthetic 5W-30 or 5W-40 will work amazingly well and with regular changes, a million miles is not out of the question. The million mile van, a 5.4L version of your engine used 10W-40 and lived for 1.3 million miles!
 
You can run anything in it, 20w-50 if you so wanted. 5w-40 is easy. I went straight to 0/5w-40 in my new vvt 2021 6.2 by the next year and I'm still under powertrain warranty. Got tired of 0w-20 getting burned. A simpler engine like that won't have any issue.
 
Back
Top Bottom