Oversized Oil Filter?

I have seen a few posts in the past mentioning using a Filter for the Ford Mustang 5.0 for our 4.0 liter Jeeps.
Who does this? How much extra oil do you have to put in? Any other tips?
I am ready for an oil change and I am considering doing this. Any experience would be appreciated.

I think thats a bad idea because it will take longer to get oil pressure on cold start up. I think that MOD is for the filter relocation adaptor where the filter is turn down so it don't drain back to the pan. 4.0 filters have a anti-drain back valve.

I do it. No problems w/cold oil pressure, or start up pressure at all. It takes about an extra quart.

On a side note my pressure went from 15 at idle to 40, switching from a Fram to a Purolator pure 1. Do a search and you'll see many negatives about Fram.

The way I look at it the more oil you have circulating the better.

Check this thread for a larger NAPA alternative ECKSJAY recommends. I'm not sure if this is the Mustang filter.

http://www.naxja.org/forum/showthread.php?t=48478&highlight=bigger+oil+filter

I use this filter with no abnormal pressure issues. It's longer, and little tighter fit in my 2000, but it goes in fine. I'm not exactly sure how much more it holds over stock. Probably b/t a half and full quart more, but I put in six quarts and top off after checking the dipstick. I've found them to be spendy, though, I think this size NAPA gold is pushing $10.

12 Volt Man said:

I have seen a few posts in the past mentioning using a Filter for the Ford Mustang 5.0 for our 4.0 liter Jeeps.
Who does this? How much extra oil do you have to put in? Any other tips?
I am ready for an oil change and I am considering doing this. Any experience would be appreciated.

Click to expand...

I use a Mobil 1 M301 filter on my 2000. I beleive it's the one from the Mustang 5.0, but I'm not certain. It holds a bit more oil than stock and is supposed to be a better filter. Been running for over 2 years and have had no adverse oil pressure problems or anything like that. My dad also runs this on his 93' YJ

It's a big Ford filter (fullsize truck, IIRC), Wix number 51773, Napa Gold 1773, etc... I've noticed no issues with it taking longer to build pressure on a cold start. It just holds an extra quart of oil and has more filtering media. When I get them in bulk with friends they're cheaper than OE sized regular prices at the auto parts stores. Check out http://www.fleetfilter.com/ for case prices on the 51773.

langer1 said:

I think thats a bad idea because it will take longer to get oil pressure on cold start up. I think that MOD is for the filter relocation adaptor where the filter is turn down so it don't drain back to the pan. 4.0 filters have a anti-drain back valve.

Click to expand...

Hi ... almost all filters now have an anti-drainback valve, so there really isn't an issue with cold startup oil pressure. I use a standard "Ford Size Filter" on my '91 4.0 HO, which is a Wix size 51515. This is a *very* common size used on a ton of Ford models. It holds an extra half-quart and has the exact same anti-drainback valve as the stock size for our 4.0 (Wix size 51085). It's even a little cheaper than the size for our 4.0, since its made in higher numbers (more vehicles use this size).

It has the same size spin-on adapter and exactly the same diameter ... just longer, giving it the higher capacity.

Since it also has a larger filter element, it has more filter surface area, which will provide better flow without sacrificing filtering capabilities. More filtering surface area also allows the filter to hold more dirt without clogging up.

I called the Wix 800 tech line, and they verified that it has the same filter medium (same type of cellulosic paper) as the stock-sized filter, just more of it because the overall size is larger.

I looked into all of this very carefully and decided it was a great mod, but if I've missed something, I want to know. I only care about what's best for the motor.

One extra note: The part numbers above are for the '91 and up 4.0 only. Earlier years use a different size of threaded spin-on.

I totally agree that this is a great mod, and have run the larger filters regularly on my Jeep fleet. But my only remaining question is why the factory went with the shorter filter in the first place?

The following reasons are all I can think of:
1) Cheaper for them to use a smaller filter
2) Shorter filter allows easier engine installation during production
3) Shorter filter is less likely to contact starter on late model XJ's
4) Shorter filter allows engine to hold exactly 6 quarts of oil
5) Shorter filter ensures fast oil pressure build up even if a filter is used that doesn't have an anti-drain valve
6) ????

Perhaps there's some other reasons I haven't considered. Anyone have more ideas?

2001XJeep said:

I totally agree that this is a great mod, and have run the larger filters regularly on my Jeep fleet. But my only remaining question is why the factory went with the shorter filter in the first place?

The following reasons are all I can think of:
1) Cheaper for them to use a smaller filter
2) Shorter filter allows easier engine installation during production
3) Shorter filter is less likely to contact starter on late model XJ's
4) Shorter filter allows engine to hold exactly 6 quarts of oil
5) Shorter filter ensures fast oil pressure build up even if a filter is used that doesn't have an anti-drain valve
6) ????

Perhaps there's some other reasons I haven't considered. Anyone have more ideas?

Click to expand...

Understand all but 3 and 4. All filters I've seen that lie horizontally are a few inches up from the starter...and run parallel to it. As for capacity...umm, with my bigger filter my engine holds exactly 7 quarts.

So then, who sells Wix filters. I called the local Auto Zone and Checker Auto Parts. Neither of those places carry them. Napa? Wal-Mart?

So, you guys are talking about an FL1A filter (Motorcraft)? They are, well at least were two months ago $2.97 at Wally World. I have a 5 litre stang, it takes that filter. Cool, so I can get an FL1A for jeep also....or is there a Modification to take it. The post is not clear on that. Thanks. Scott.

I found this online. I thouhgt they had Anti-Drain back Valves. I can tell you from experience this filter is a Great one. I have a Stock 1989 5.0 Mustang, the valve covers have never been removed or the engine touched. I have over 450 Thousand miles on the engine. All I used was FL1A's and Castrol GTX 10W-30 every 3000 miles. I am going to switch to this filter. THANKS GUYS!!! Scott



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Motorcraft Oil Filters


Code: ACOFLseries
Options: Type Please Select(#FL1A) Filter(#FL820) Filter(#FL400S) Filter (+.50)

Availability: Usually ships the next business day.
Regular price: $3.95
Wholesale price: $3.95, 12/$35.40






Every Motorcraft filter delivers the quality performance you’ve come to expect from Ford Motor Company products. They’re the only filters designed, engineered and recommended specifically for Ford, Lincoln and Mercury vehicles. Engineered specifically for Ford, Lincoln and Mercury vehicles, each Motorcraft oil filter, including the popular Motorcraft FL1A, uses as many as 12 high-quality components.


Construction features include:
Steel Cases
"Ironed" for a precise fit, fluted to ease removal and painted for rust-resistance.

Pressure Relief Valve
When it's cold outside or if the filter becomes clogged, oil flow through the filter can be reduced. If this happens, the relief valve opens to provide a continuous oil supply. Its design also minimizes the chance of contaminated oil recirculating back into the engine.

Anti-Drain Back Valve
This feature keeps oil in the filter to prevent "dry starts" after your engine has been turned off. It's made with specially formulated material that resists the aging effects that an engine's heat can cause.

Efficient Filter Media
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12 Volt Man said:

So then, who sells Wix filters. I called the local Auto Zone and Checker Auto Parts. Neither of those places carry them. Napa? Wal-Mart?

Click to expand...

Same question... what's this "WIX" stuff?

12 Volt Man said:

So then, who sells Wix filters. I called the local Auto Zone and Checker Auto Parts. Neither of those places carry them. Napa? Wal-Mart?

Click to expand...

NAPA filters are Wix. Asked them since its NAPA branded, parts guy says all their filters are manufactured by Wix.

ECKSJAY said:

Understand all but 3 and 4. All filters I've seen that lie horizontally are a few inches up from the starter...and run parallel to it. As for capacity...umm, with my bigger filter my engine holds exactly 7 quarts.

Click to expand...

On my 2001, running the longer filter only leaves about 1/2" or less clearance between the starter solenoid and the oil filter. Not enough to interfere, but it would contact it when installing/removing if not careful. The oversize filters I've been using hold 1/2 quart so the engine takes 6.5qts.

My ZJ and TJ both have the filter pointing straight out the side of the block and there's plenty of clearance to run a much longer than stock filter. But it is nice to have one case of oil perfectly cover two vehicles.

ODXJ97 said:

Same question... what's this "WIX" stuff?

Click to expand...

Great quality brand.

For Wix, see also Napa and Carquest. Follow the link above that I provided and there's a cross-reference chart on that site. Note their part numbers. Those who sell their branded filters often use the Wix number with a slight variation. IIRC, Carquest's number would be 151773 whereas Wix number is 51773, and Napa is 1773.

i just started using a ford motorcraft FL1A and have been very happy with it. i did some searching and it appears it's the same exact filter as a purolator pureone (PL30001), but for about half the price.

2001XJeep said:

I totally agree that this is a great mod, and have run the larger filters regularly on my Jeep fleet. But my only remaining question is why the factory went with the shorter filter in the first place?

Click to expand...

The filter on XJs that don't have the metric one (older) is the same one that has been used on all sorts of Dodge/Chrysler vehciles for a while. I think its cheaper for them (economies of scale) to use the same filter- its Napa part 1085- across their fleet.

OK, update after a trip to NAPA today. I looked at the NAPA Gold Filters. The guy at the counter confirmed they are made by WIX. I looked at two options the 1515 which is for a Ford 5.0. It is approx 2 inches longer than the stock sized one. Then there is the 1773, it is approx 4 inches longer than the stock one. The 1515 looks like it will hold about a 1/2 quart more oil, and the 1773 (total of 7 inches long) looks like it will hold a quart extra oil.

I went with the 1515 for this oil change. I may try the 1773 next time. The guy at the counter check the specks on the filters and they match up to the stock recommended one as far as threads and anti-drainback valves etc.....

I think as long as you keep good oil pressure, both are a viable option.

Now, I gotta figure out which Mobil 1 filter is a match to either of those. Autozone has a deal for 5 quarts of Mobil 1 and a filter for $30.00.

12 Volt Man said:

Now, I gotta figure out which Mobil 1 filter is a match to either of those. Autozone has a deal for 5 quarts of Mobil 1 and a filter for $30.00.

Click to expand...

You can call the Mobil 1 Oil Filter Hotline at 1-800-882-0890.

Hours are Monday to Friday, 7 am to 8 pm (Central Standard Time), on Saturdays from 7 am to 5 pm (CST), and on Sundays, from 11 to 3 pm (CST).

They will give you the cross reference part number.