oil filter change interval for 7.3L PSD?

[craftyone]

How long can I go without changing my oil filter?

- 2003 Ford F250 7.3L SD 2WD
- current 187182 miles
- last oil change (with Motorcraft filter) 183100 on August 18, 2024
- not a daily driver, 10k miles hauling 5th wheel trailer until 2007, light duty around town now (Louisiana).

So with only 4k miles on this oil and filter I want to just drain filter, visual check and reuse but this oul/filter change will take me past August 2025 and that’s over 1 year same filter.
Is this an issue? Searching interwebs I get “change within a year”. Oil, Rotella T4 (see pic) is super clean. Just curious since those 1995 filters went from $9 to $27-30. Have one more Motorcraft then I start using the Doc’s diesel filters btw.
Later….

 

[oil pan 4]

Search my posts. It's a long time.

 

[ripcord]

I'm not totally clear on what you wrote, but that dipstick sure looks clean for a diesel. You must have just put clean oil in it. You can get away with using the filter that's in it for more than 4k miles but some would say it's not ideal. The 7.3l Powerstroke should be changed every 5k miles for best life and performance of your fuel injection system.

One thing to know is that you should never put an oil filter back on that you have removed, as the gasket on the oil filter is not designed to be reused. You're just asking for an instant 15 quart gushing leak if you do. If you want to use a filter for two oil changes, just leave it alone until you are done with it.

 

[Lubener]

I am not a big supporter of running filters for two change intervals. With 4k miles accrued since last August , I would run the oil a little longer and change both the oil and filter around August . That should be with no more than 6k miles at your present driving habits.

 

[fantastic]

4k on that oil in the picture on 7.3L diesel, How in the world is that oil so clean? With oil that clean run them both double to 8k.

 

[demarpaint]

Impressively clean oil for a diesel. I'm not a fan of draining and reusing filters, it's a great way to cause them to leak.

 

[billt460]

I'm having a difficult time believing that oil went 4K in a diesel.

 

[Titan]

I had a 4.6 modular gas Ford engine that I left the Motorcraft filter on for 3 oil change intervals of 5000 miles. UOA's showed the "Insolubles" dropped each interval. I don't remember the first two reports, but the final interval (after 15,000 miles) I remember the Insolubles were reported as 0.1. I didn't try 4 intervals.

 

[BC1]

If you have a 1995a filter check the louvers good to see if they are open. They are not the no-brainer go to they used to be as 1995. I gave up on them due to poor quality. For a 2wd give the Donaldson P550371 a look, it is cheaper that the motorcraft. DBL7405 for 4wd.

 

[johnmyster]

Given the headache of HPOP and injectors, why push things on a recreational use irreplaceable truck? Use good oil. Use good filters (not docs.) There are other good-to-great filters out there. If the motorcraft price is not tolerable, why not consider:

Fleetguard Stratopore (LF3974?)
Donaldson (P550371?)
Baldwin (B7039?)
CarQuest Premium?, Caterpillar 1R-0716?, Luber-Finer LFP4005?

My first stop would be the Fleetguard (if I could locate it) unless I could find a good price on the correct Donaldson. Even a Wix 51734 is certainly good enough.

In the end it's less than $100 per year different between a stretched interval do the minimum T4 plan and Delo XSP twice a year and higher tier filter treatment.

 

[userfriendly]

I'm having a difficult time believing that oil went 4K in a diesel.

My deleted LML Duramax stays clean like that. Before the delete, it would be black the next day.
With the price of oil filters doubling in the last few years, you might as well get your money’s worth.

 

[DirectRejection]

How long can I go without changing my oil filter?

- 2003 Ford F250 7.3L SD 2WD
- current 187182 miles
- last oil change (with Motorcraft filter) 183100 on August 18, 2024
- not a daily driver, 10k miles hauling 5th wheel trailer until 2007, light duty around town now (Louisiana).

So with only 4k miles on this oil and filter I want to just drain filter, visual check and reuse but this oul/filter change will take me past August 2025 and that’s over 1 year same filter.
Is this an issue? Searching interwebs I get “change within a year”. Oil, Rotella T4 (see pic) is super clean. Just curious since those 1995 filters went from $9 to $27-30. Have one more Motorcraft then I start using the Doc’s diesel filters btw.
Later….

View attachment 282731

I strongly recommend you watch the Sprinter Fix YouTube video I posted a link to in the Mechanical Forum. He talks with BITOG favorite Lake Speed Jr.

BTW Lake Speed Jr has close contacts at Cummins, Donaldson, etc, plus he sits on the voting committee at ASTM, therefore his bonafides are to be respected.

Golden nugget comments are made about diesels and PSD. It would be very useful for diesel (and TGDI) owners to soak up every detail, but here are some highlights.

The ASTM test for diesel fuel cleanliness is 20 years old. US diesel fuels are lacking in detergency. Fuel filters are of tantamount importance. Microns + efficiency must be careful scrutinized. Soot handling capability is key. PSD has a unique DPF/EGR regeneration strategy and must be accounted for. Take Delo 300 vs old school Rotella. Modern is much better, even with dosage restrictions...

 

[BC1]

The 7.3 does not have any thing but a muffler(maybe) after the turbo. No DPF/EGR/SCR/catalytic converter/regen ect.

 

[DirectRejection]

The 7.3 does not have any thing but a muffler(maybe) after the turbo. No DPF/EGR/SCR/catalytic converter/regen ect.

Thank you. There were comments that apply to both 7.3 & 6.7 and some were emissions related.

The subject focused upon was Mercedes Benz I-5 & V6 diesels. The V6 was put in a MB SUV with tuning and a half sized oil sump, with interesting results.

Some of this stuff is universal and eye opening.

 

[aquartlow]

FWIW, I have 415K+ on my 2000 F250 7.3 6spd 4x4 and I change it's oil at around 3.5-4K miles(yeah lots of oil and filters over it's lifetime)-just think about how much fuel has been through the original fuel pump at 14 mpg average . It still runs great, starts immediately, fairly quiet(makes a difference when I retorqued the rockers/injectors), original injectors that I shimmed the solenoids once. It has towed a 10K lb gooseneck around 2/3 of the mileage accrued. Good Oil/filters are cheap compared to any diesel engine repairs.

 

[oil pan 4]

I am not a big supporter of running filters for two change intervals. With 4k miles accrued since last August , I would run the oil a little longer and change both the oil and filter around August . That should be with no more than 6k miles at your present driving habits.

I've seen the OCD ran for multiple change intervals on diesels, and they're always just fine.

 

[dnewton3]

OIl filters are most certainly capable of running long OCIs, or multiple shorter OCIs.

I think the concern today is about the quality of filters, from all the brands. If you have a well-made filter, then there is no reason to think it wouldn't go 2x the OCI (8k miles rather than 4k miles in the OPs application). But who's to say if the filter installed is a "quality" product these days?

Example 1:
Install a filter, run for 4k miles. Is that filter well made and has no defects? It's Schrodinger's filter ... you don't know until you cut it apart.
After you install a new filter, for another 4k miles, it too is a total guess. You may have just installed a bad filter for the next 4k miles, even if the first one was good. Those two filters have no influence upon the other; they are unique singular events with no realm of influence past their own existence.

Example 2:
Install a filter and run for 8k miles. Is it good? Who knows? If it is good, then you have a high degree of likelihood of success over 8k miles. But if it's bad, you double down on the badness ...

My point being, the duration of the filter change interval (FCI) has no bearing on the success or failure of the filter itself. The quality of construction is not dependent upon the FCI interval. These are independent parameters. The risk of failure is no more or less, regardless of the duration of use.


Assuming the filter is good out of the box, there is plenty of proof that a filter can easily go 10k miles in most applications.


I've posted some recent filter dissections, used in some less-than-BITOG-ideal conditions. Yet everything was fine.

Thread 'NG 1311 engine oil filter; 150 hours, 4 years.'

May 15, 2025

From my Kubota L3430.
150 hours in 4 years of use.
Media was perfectly fine; no voids or tears. Had minimal loading of the media.
Silicone ADBV was pliable.
Construction was good. (back when Wix made decent filters)
Oil was VPB 10w-30 HDEO.

Same oil and filter went into service; the last of my old stock.

• dnewton3
• Replies: 2
• Forum: Engine Oil Filters

• 

Post in thread 'Ariens 09414200 hyd filter'

May 15, 2025

Hydraulic systems like this generally come up to full temp, and keep the moisture out. It's not like an engine; where one of the byproducts of combustion is water vapor. So the oil stays fairly clear of any moisture inside the system. Hence no rust or corrosion, generally. So as long as the oil stays reasonably free of contamination, there's no real reason to think that a few years is a limit for a filter. 10 years and this was just fine internally. Even externally, the only indication was some rust on the base plate; not anywhere close to a risk of rusting through.

• dnewton3

• 

 

[Ruby]

The 7.3 was a great motor for the F250- F350 Trucks, which were made by International. I had a 2002 F350 with the 7.3, again great motor, dependable and easy to work on. When I had my 7.3, I used to buy the 3- 5 quart jugs of Motor Craft 15w40 and the Motor Craft Oil Filter (FL1995) at WM.

There were never any issues, I changed the oil/oil filter every 5000 miles. The oil stayed pretty clean because the emissions components were not on the 7.3's which kept the oil much cleaner. The only reason I no longer own this truck was because it kept rusting out, otherwise I would still have it.

My current truck, 2011 Ram 3500 with the Cummins 6.7 holds 12 quarts of oil. I use Shell Rotella T6 Synthetic 5w40 and change the oil and filter every 5000 miles although the Manuel indicates 7500 miles. I can use the 15w40 oil at temperatures at zero or above, or the 5w40 diesel oil year round. I choose to run the 5w40 year round because it covers all temperatures. Because of the emissions components on my truck, the oil is pretty dark/black right after a fresh oil change.

 

[DirectRejection]

In the other thread, I should have said 40 years ! Diesel fuel cleanliness ASTM test us that old. It is crazy with the seachanges involving emissions.

 

[Ruby]

I'm not an environment expert, but I question all the emissions components on the diesel trucks 2007 to date. These components starve engines of power and fuel milage. It all started with the ULSD which you think would have been good enough to keep environmentalist happy. In fact, the emissions standards that were coming put a stop to the 7.3 in mid 2003, then the 6.0 was introduced.

Although, I really like my 6.7 Cummins, the 7.3 was one heck of a motor.