Severe service?

Joined
Sep 3, 2005
Messages
227
Location
Royal Oak MI.
Hi guys,im running Motorcraft 5w20 in my grand marquis at 5,000 intervals. I am using the car for my job as a Private driver and car sits idling for 2,3 hrs. at a time 3 or 4 times a week. Based on this,what oil and interval would you suggest? Car has 23,000 miles,no consumption. 2004 Grand Marquis. Hope everyone is doing well. Thanks for any advice.
 
Last edited:
Joined
Sep 6, 2009
Messages
524
Location
Lead, South Dakota
Just run whatever synthetic 5W30 you find for a good price. Cop cars and taxis are used similarly, and I guarantee that the fleet managers for your local PD and Taxi company are using the cheapest oil they can. If you want some additional peace of mind, Rotella T6 would work just fine and isn't to expensive. Long idles are a reality for commercial vehicles, so I'd imagine the Rotella is designed to handle those sorts of things.
 
Last edited:
Joined
Mar 24, 2010
Messages
657
Location
Chicago Suburbs
we ran QSUD 5w30 in our police fleet in CVPI's with a 4.6 when I was a trustee and fire and police commissioner ,, we had no issues , sometimes our cars caught 12 -15 hrs a day at idle ,,,,,,
 
Joined
Dec 15, 2017
Messages
3,275
Location
On another site
Definitely 5W-30, It was the original specification for that engine. If you are only going 5000 between changes, any synthetic should be able to handle that easily.
 

blupupher

Site Donor 2021
Joined
Aug 27, 2004
Messages
7,139
Location
Katy, Republic of Texas
Stick with 5w-20 and 5,000 miles, why, because my opinion matters as much as everyone elses (not much at all). Seriously, seems a lot of thin hate lately with absolutely no proof of any issues with it. And the argument that "it was originally spec'ed for 5w-30" is not a valid argument, maybe engineers found that 5w-20 is a better oil for it (since 5w-20 was not around in abundance when the 4.6 modular was designed). And yes, CAFE played a part in it, but not all. I am still looking for the millions of 2v modular motors with engine failure due to 5w-20 being used.
 
Joined
Jul 15, 2005
Messages
13,194
Location
Maricopa Arizona
Originally Posted by blupupher
Stick with 5w-20 and 5,000 miles, why, because my opinion matters as much as everyone elses (not much at all). Seriously, seems a lot of thin hate lately with absolutely no proof of any issues with it. And the argument that "it was originally spec'ed for 5w-30" is not a valid argument, maybe engineers found that 5w-20 is a better oil for it (since 5w-20 was not around in abundance when the 4.6 modular was designed). And yes, CAFE played a part in it, but not all. I am still looking for the millions of 2v modular motors with engine failure due to 5w-20 being used.
This engine and engine family gets 5W20 on cheapo bulk in fleet use and the idle time in the desert is a lot more than the OP is stating for his vehicle. Then to top it off they are then immediately thrown into WOT after hours of idle.
 
Joined
Mar 3, 2017
Messages
1,177
Location
WA
Give Castrol Magnatec 5w30 a try. Makes my Kia so smooth, runs better than with any other name brand 5w20.
 
Joined
Sep 1, 2008
Messages
5,337
Location
Southeast Texas
Originally Posted by blupupher
Seriously, seems a lot of thin hate lately with absolutely no proof of any issues with it.
Its not "thin hate" to point out to readers of this forum the facts about CAFE. When an engine is spec'ed for 5-30 all around the globe except in the CAFE restricted USA, its very noteworthy. Even many owners manuals now say "adequate" protection with 5-20, instead of "optimal". "Hate" is way too strong of a word. The word that comes to my mind is "truth".
 
Joined
Jul 3, 2005
Messages
36,254
Location
NY
Originally Posted by tiger862
I would put hour meter on vehicle and change every 200 hours.
That's a very good idea. A UOA at the 200 hour drain would help in establishing just how far the oil can go, if the desire to find out is there.
 

pbm

Joined
Apr 19, 2004
Messages
9,050
Location
New York
I'd compromise and use a 'thin' 5w30 synthetic like Pennzoil Platinum. PS: Idling is probably tougher on an engine than regular driving so if I were idling a few hours a day I wouldn't go beyond a 5K OCI even on synthetic.
 
Joined
Jan 28, 2018
Messages
397
Location
Missouri
Originally Posted by dave1251
Originally Posted by blupupher
Stick with 5w-20 and 5,000 miles, why, because my opinion matters as much as everyone elses (not much at all). Seriously, seems a lot of thin hate lately with absolutely no proof of any issues with it. And the argument that "it was originally spec'ed for 5w-30" is not a valid argument, maybe engineers found that 5w-20 is a better oil for it (since 5w-20 was not around in abundance when the 4.6 modular was designed). And yes, CAFE played a part in it, but not all. I am still looking for the millions of 2v modular motors with engine failure due to 5w-20 being used.
This engine and engine family gets 5W20 on cheapo bulk in fleet use and the idle time in the desert is a lot more than the OP is stating for his vehicle. Then to top it off they are then immediately thrown into WOT after hours of idle.
I worked at a prison for a little over a year and we had a few crown Vic's that were used to patrol the perimeter of the complex, 24 hours a day they idled around, never exceeding 5 mph and never shut off not even during refueling, I'm unsure what oil they used but in my time there they only put around 600 miles on them
 
Joined
Mar 30, 2015
Messages
7,031
Location
Lake Havasu City, Arizona
Originally Posted by mrjlube
Hi guys,im running Motorcraft 5w20 in my grand marquis at 5,000 intervals. I am using the car for my job as a Private driver and car sits idling for 2,3 hrs. at a time 3 or 4 times a week.
Translate that into miles. Both my newer Jeep and Toyota barely turn 1,200 to 1,400 RPM at a steady 40 MPH. So your engine is effectively turning at idle about half of that, (650-700 RPM). Yeah, it's not under a load, but there really isn't much load rolling down a flat, level road at 40 MPH either. The hour meter is a very good suggestion. I would go with that due to the amount of idling your engine is experiencing. A lot of cop cars and taxi's use them, as do boats. Many cars already have them. My Jeep has a total hour meter associated with the trip odometer. It's amazing how slow your average speed is, when you incorporate the hours the engine runs into the equation.
 
Joined
Jul 3, 2005
Messages
36,254
Location
NY
Originally Posted by billt460
The hour meter is a very good suggestion. I would go with that due to the amount of idling your engine is experiencing. A lot of cop cars and taxi's use them, as do boats. Many cars already have them. My Jeep has a total hour meter associated with the trip odometer. It's amazing how slow your average speed is, when you incorporate the hours the engine runs into the equation.
My Jeeps have that hour meter. I did the math a few times with my wife's Liberty, the average speed is sickening. IIRC is was under 20 mph. You gotta love Long Island and the NY Metropolitan area.
 
Joined
Oct 3, 2008
Messages
4,643
Location
Kuwait
If memory serves me right, 1 hour of idling is equal to 33 miles according to Ford. If you're idling 3 hours a time, 4 times a week that is 396 miles. Where you are, I would run an xW-30 meeting ACEA A3/B4, or even an xW-40 HDEO if you want to switch.
 
Top