Oil Change Question

[realshelby]

Bypass is psi dependent. The smaller micron the higher psi. So for synthetic-which is “clean” oil, extended interval filters have larger micron media because they do not need to be as fine and keeps from bypassing as much as soon.

Not always true. If you have enough filter area the psi across the filter is going to be similar from a 20 micron to a 40 micron filter. Only, and ONLY when a filter has become contaminated beyond normal load should you have notable bypass at operating temperature!
No where has any manufacturer listed a suggestion about synthetic oil qualifying for a larger micron filter that I have found. Wear particles are wear particles, no matter what oil is being used. Microscopic metal particles and especially silica particles need filtered out!

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[Saxapl]

Not always true. If you have enough filter area the psi across the filter is going to be similar from a 20 micron to a 40 micron filter. Only, and ONLY when a filter has become contaminated beyond normal load should you have notable bypass at operating temperature!
No where has any manufacturer listed a suggestion about synthetic oil qualifying for a larger micron filter that I have found. Wear particles are wear particles, no matter what oil is being used. Microscopic metal particles and especially silica particles need filtered out!

Oh I think they are constant bypass. A 51348 bypasses at 8-11 psi. There is going to be constant bypass due to normal operating pressure. That filter, which is the same for a Briggs twin, does not have the ability to filter all oil all the time. And you run more oil pressure than 11 pounds meaning you are always bypassing to some degree.

But again, I can only say what Wix says about its product. I have no independent data other than manufacturer data, so maybe you have something more.

 

[realshelby]

I think you need to research what "bypass" pressure means...
The 8-11 psi you mention is a fairly common bypass pressure...BUT THAT DOES NOT MEAN IT STARTS BYPASSING AT 8-11 PSI of oil pressure! That is the rating where the difference between filter input pressure is 8-11 psi higher than filter output pressure! So you could have 60 psi of oil pressure showing at your main oil feed into the engine and have zero bypass occurring. Now if you have 60 psi coming into the filter housing....and the oil pressure leaving the filter housing drops to 49-52 psi your oil filter bypass valve would in fact begin to open to equalize pressure ( assuming an 8-11 psi rated valve) so it won't drop further. That does not mean there is NO oil going through the filter and being filtered, but it does mean that SOME oil is bypassing the filter media. There are different bypass valve ratings, but all are simply the DIFFERENTAL in oil pressure between incoming and outgoing oil pressures.

 

[MakinDoForNow]

Gee. I bought a Ford used fleet car in 1975 that had 108,000 miles in it. It was run all that time on natural gas but the nat gas tanks and equipment were removed just before I purchased it I changed the oil every 5k miles and I did not notice any darkening of the oil until 15-20k miles after I bought it.

 

[Saxapl]

I think you need to research what "bypass" pressure means...
The 8-11 psi you mention is a fairly common bypass pressure...BUT THAT DOES NOT MEAN IT STARTS BYPASSING AT 8-11 PSI of oil pressure! That is the rating where the difference between filter input pressure is 8-11 psi higher than filter output pressure! So you could have 60 psi of oil pressure showing at your main oil feed into the engine and have zero bypass occurring. Now if you have 60 psi coming into the filter housing....and the oil pressure leaving the filter housing drops to 49-52 psi your oil filter bypass valve would in fact begin to open to equalize pressure ( assuming an 8-11 psi rated valve) so it won't drop further. That does not mean there is NO oil going through the filter and being filtered, but it does mean that SOME oil is bypassing the filter media. There are different bypass valve ratings, but all are simply the DIFFERENTAL in oil pressure between incoming and outgoing oil pressures.

I certainly agree with your description. All bypass valves work based upon pressure differential. But I think where we are apart is that I do not agree that a bypass means no oil goes through the filter. . When you start the motor, you are in bypass. Incoming pressure is high psi compared to zero. As post housing pressure builds, the bypass still operates to regulate pressure. The filter media cannot handle the volume of all the oil all the time. Nor does it need to as some amount of bypassed oil is normal and will be filtered at some point. When you think about 5 qts of oil, it will all cycle relatively routinely.

There are specific bypass filter systems (engine bypass) for the very reason of increasing filtering capacity…or quantity more precisely.

I’m thinking we are saying the same thing…except for maybe you disagree that there is always some amount of bypass? Which I say there is. But I certainly agree with you that bypass is based upon pressure diff and that you do not have full bypass all the time. You simply cannot run at normal oil pressure and not see a 8-11 psi differential on the back side of a 21 micron 51348 due to impedance. It will always bypass to relieve some pressure in normal operation.

But again…just what the Wix guy says. I’ve never done my own research.

 

[realshelby]

I’m thinking we are saying the same thing…

No, we are NOT saying the same thing.
I am going to try to bow out of this. I hope my explanations have cleared up what bypass means in normal automotive filtration systems and how it acts....

 

[MaverickTopGun]

.........You simply cannot run at normal oil pressure and not see a 8-11 psi differential on the back side of a 21 micron 51348 due to impedance. It will always bypass to relieve some pressure in normal operation.

Bypass can occur with cold, thick oil on start-up, or when revving hard while cold.
https://bobistheoilguy.com/forums/threads/question-about-filter-bypass.200435/#post-3067880

 

[Saxapl]

Bypass can occur with cold, thick oil on start-up, or when revving hard while cold.
https://bobistheoilguy.com/forums/threads/question-about-filter-bypass.200435/#post-3067880

Indeed. Agree. It does and it can.
Filters spend a great deal of their time bypassing. It is normal operation. I pulled a post from the same site which says that as well in case the filter manufacturers are not to be believed. But internet posts are…internet posts.

Regardless…this got off topic. Sampling. I think that is not controversial. If you really want to know what is happening, sample.

Here is the post:
Post in thread 'What does filter extended duration actually mean?'
https://bobistheoilguy.com/forums/t...ed-duration-actually-mean.366469/post-6426188

 

[Motorjunkie]

Don’t listen to ppl who aren’t mechanics. Change your oil at the very most 5k miles.

Tradition is not a good reason to keep doing things the old way. As a former Mercedes tech, I did a lot of business with All European Auto in Michigan. They used Dodge Sprinter vans with the Mercedes turbo diesel. They used Amsoil exclusively and ran those vans for years at 25k mile intervals. As oil AND engine technology gets better, we can stretch the old intervals beyond what used to be the norm. But in any case, stick with the Ford recommendation throughout the warranty period. Experience is the best teacher.

 

[MaverickTopGun]

Filters spend a great deal of their time bypassing. It is normal operation.

I don't agree. Bypassing is not often. Briefly happens when it does occur.

In the bobistheoilguy post I linked to above, users Jim Allen, ZeeOSix, Motorking, and dnewton3 all say, based on experiments and basic fluid mechanics, bypass events are brief & quick. Thick, cold oil can make it happen at first on start-up, but not for long. The Motorking user was a Fram Tech Rep who really knows oil filters. The rest are engineers.

To really minimize bypass events, our Maverick can use the bigger FL400S or Fram Titanium FS3600 to lower the pressure differential a bit. Helps some anyway.

 

[john218]

Can we please “bypass” the need to argue back and forth?

 

[cjwagner]

Anyone care to weigh in on this?

Oil Change Reminder
Your vehicle comes with an oil change reminder that determines when you should change the engine oil based on how you use your vehicle.
Your vehicle lets you know when an oil change is due by displaying a message in the information display.
The following table provides examples of vehicle use and its impact on oil change intervals. It is a guideline only. Actual oil change intervals depend on several factors and generally decrease with severity of use.

When to Expect the OIL CHANGE REQUIRED Message
Interval Vehicle Use and Example
7500–10000 mi (12,000–16,000 km) Normal Normal commuting with highway driving No, or moderate, load or towing Flat to moderately hilly roads No extended idling
5000–7500 mi (8,000–12,000 km) Severe Moderate to heavy load or towing Mountainous or off-road conditions Extended idling Extended hot or cold operation
3000–5000 mi (5,000–8,000 km) Extreme Maximum load or towing Extreme hot or cold operation Extended engine idling


https://www.fordservicecontent.com/...ingEnabled=False&userMarket=USA&buildtype=web

 

[Bobby130]

Wow! Way more BS than fact in this thread!!!

If you don't have an oil sample analysis readout to PROVE your theory about oil ( and filters...) you really cannot say you are correct or full of BS.
An oil analysis will tell you if ANY fuel is getting into your Ecoboosts oil, will tell you if there is dirt in your oil ( you know, those pesky bypassing oil filters with 5K miles on them...), will tell you how your oil additive package is doing, and many other things.....
You can still change your oil and filter at 3,000 miles if it pleases you. Just know there are many cases of engine damage from oil filters not being correctly tightened and oil drain plugs not being tightened so doing oil changes 3 times or more the recommended intervals does not necessarily reduce risk of engine damage....if you happened to forget to tighten your drain plug or missed the oil filter seal that stuck to the block and you put on the new filter without noticing it....

I was a Master tech for 36 years at Honda and I change my own oil at 5000 miles. Then I can look underneath for leaks or anything that might be a problem. When at Honda they had a problem with oil burning .So if you were to wait untill 7500 or 10000 miles you would have run out of oil. Hondas we’re not the only ones with oil burning. Chevy Toyota and many others. Just a note about going to a dealer for service. Get them to take a tour of the shop. Look around for underneath shields. If you see a few stacked around the shop you need to find a different dealer. What else did they leave off or loose? At my own dealer there were too many left off but no one cared. A lot of oil plugs were left loose or left out .Oil filters double gaskets and blowing before it left the shop. Choose your dealer wisely.

 

[Guv]

Oil life monitors track climate, driving habits and other conditions. The algorithm calculates mileage, idle time, engine temperatures, trip times, engine loads, and ignition starts and stops. It then establishes an oil change interval as low as 3,000 miles (4,800 km) and all the way up to 10,000 miles (16,000 km) and more depending on severity of conditions.

Purposely not resetting the Oil Life I have had an oil change alert after less than a 1,000 miles following an oil/filter change with M1. This was on my 2019
F-150 5.0. Makes me think it’s not quite as complex or advanced as advertised.

 

[JennyJoannSuebeeMcNash]

I was a Master tech for 36 years at Honda and I change my own oil at 5000 miles. Then I can look underneath for leaks or anything that might be a problem. When at Honda they had a problem with oil burning .So if you were to wait untill 7500 or 10000 miles you would have run out of oil. Hondas we’re not the only ones with oil burning. Chevy Toyota and many others. Just a note about going to a dealer for service. Get them to take a tour of the shop. Look around for underneath shields. If you see a few stacked around the shop you need to find a different dealer. What else did they leave off or loose? At my own dealer there were too many left off but no one cared. A lot of oil plugs were left loose or left out .Oil filters double gaskets and blowing before it left the shop. Choose your dealer wisely.

I gave up my 2014 Accord LX-MT (only 84K miles!) for a Maverick because of the burning oil/gasket leak issues. My (non-Honda) mechanic said the 2014 engines were plagued with issues. Would like to hear more about this issue from an actual Honda tech. Thanks!

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