dual oilfilters

[Joseph Upson]

Two oil filters wouldn't hurt but if you can do the same with one large filter that would be better. What hasn't been mentioned is the ability of the oil filter to be bypassed under some conditions, related to high viscosity or higher than normal flow such as during high rpm.

I plugged the by-pass valve in a 3.4L block once to force all of the oil through the filter. It came back to haunt me when a fouled up cam install due to a rocker nut backing off and coil bind resulting in cam failure. Before draining the oil I decided to run engine flush through the engine to help flush out the metal (you're supposed to use kerosene, that's what crane said).

In a matter of moments the oil filter clogged and actually stalled the engine since the by-pass was plugged. I believe I increased the spring pressure on the oil pump also. A dual filter might not have allowed that to happen.

There has to be an upside to dual or there is absolutely no basis for offering such an upgrade. I could be wrong though. I would reason that the more contaminants removed from the oil the longer it remains serviceable, at least a demonstration I watched years ago proved that point using toilet paper to filter out more contaminants resulting in much longer oil life as made evident by the test engines performance with highly filtered high mileage oil.

[pocket-rocket]

Well if for some reason you didn't change the filters when they were supposed to be changed and the first one got clogged and started bypassing, the second would be there to pick up the slack. But then you have pretty much everyone on this board that keeps up on the oil/filter change, so that makes it worthless. Over time I would rather do 1 large one to help keep operating costs lower then 2x filters.

[Joseph Upson]

Well if for some reason you didn't change the filters when they were supposed to be changed and the first one got clogged and started bypassing, the second would be there to pick up the slack. But then you have pretty much everyone on this board that keeps up on the oil/filter change, so that makes it worthless. Over time I would rather do 1 large one to help keep operating costs lower then 2x filters.

If everyone in the U.S. starting today changed their oil exactly when it was necessary and not a day sooner, I seriously wonder what kind of effect it would have on the price we pay for it today especially in our current situation. If a measure could be taken to increase oil life above what it is currently in addition to that how much more would we benefit?

I believe there is a natural urge for us motor heads to over-do and upgrade. Many of us have made additions and upgrades that far exceed what is actually necessary for sufficient engine life expectancy. A good example of the importance of moves like this is the oil life monitoring systems being incorporated into modern vehicles now.

It does two very important things, one in the wake of warranty and the other the increasing costs of fossil fuel and that is to insure you change your oil when it's necessary to avoid damage to the engine and to avoid the wasting of a limited natural resource.

In my opinion, changing oil long before it is actually necessary is a far greater waste than adding an additional oil filter. In my very first car with a 2.8L purchased new I didn't perform the first oil change until it had 10k on it and then about every 7k after that. When I sold it with more than 140k miles on the odometer, it still ran strong and didn't have a knock or tick despite having been overheated twice and run out of oil once from a leaking valve cover.

It was driven nearly a quarter of a mile after the valves started tapping to a parking space on campus before being shut down. Now that was a tough Firebird and proof positive that oil resiliance is much greater than we acknowledge.

For years car owners have in my opinion been induced to paranoid oil changes (every 3000 miles) for the sake of generating regular profit for service providers.

If everyone in the U.S. starting today changed their oil exactly when it was necessary and not a day sooner, I seriously wonder what kind of effect it would have on the price we pay for it today especially in our current situation.

Certainly we all know that increasing fuel economy of our vehicles would have an effect, despite the auto manufacturers reluctance to do so. Am I the only one to notice that there is no real reason for our cars to weigh as much as they do today, an 08 Malibu weighs 3415 lbs nearly 400 lbs heavier than the 2000, it makes no sense to me.

The metals are much better and so is the oil, I believe a conservative effort to reduce oil consumption will do us a lot of good right now. Cooler running better filtered oil can reduce the frequency of oil changes and save us a lot of money. Some owners manuals already recommend 7k oil change intervals, synthetic should at least get you 10k.

What do you think?

[bszopi]

I believe there is a natural urge for us motor heads to over-do and upgrade. Many of us have made additions and upgrades that far exceed what is actually necessary for sufficient engine life expectancy. A good example of the importance of moves like this is the oil life monitoring systems being incorporated into modern vehicles now.

On my wife's Alero (2003 with the 2.2 Eco-Tec), I only change the oil when the light comes on. In the 2-3 years we have owned the car, it usually comes on at around 7k miles.

Am I the only one to notice that there is no real reason for our cars to weigh as much as they do today, an 08 Malibu weighs 3415 lbs nearly 400 lbs heavier than the 2000, it makes no sense to me.

Creature comforts and safety. Navigation systems, 8 speaker sound systems, side curtain airbags, impact crush zones. You name it, it adds weight to the vehicle. Oh, and the fact that the 2008 Malibu is significantly larger than the 2000 probably helps a little bit as well.

[IsaacHayes]

A friend was working on a 70 or 71 mustang putting in a new clutch and replacing the mechanical linkage to the clutch (all worn out and he had to make new stuff) on the top loader trans and I noticed the OEM sticker said to change oil every 6,000 miles!!! Wow back in the 70's!!! Back when oil wasn't as good as it is today.

[pocket-rocket]

Well I change my oil about every 7k miles or so, sometimes later depending on my budget situation. Then again, I use synthetic as well, but I don't watch the odometer like a hawk and pinpoint where I can go to get the 7k rollover to land me in my drive. What I meant by my comment was that most of the people on this board are performance people and take more care of our cars then the average Joe. I wonder how those oil monitoring systems work and if they could be removed from a junk yard car and put in an older one...

[Joseph Upson]

Well I change my oil about every 7k miles or so, sometimes later depending on my budget situation. Then again, I use synthetic as well, but I don't watch the odometer like a hawk and pinpoint where I can go to get the 7k rollover to land me in my drive. What I meant by my comment was that most of the people on this board are performance people and take more care of our cars then the average Joe. I wonder how those oil monitoring systems work and if they could be removed from a junk yard car and put in an older one...

The monitor is probably set to consider the poorest market quality oil you can put in the car, then based on a preset mileage expectancy, it probably deducts mileage life based on a time, mileage, speed and temperature algorithm, which would allow differentiation between hwy usage (the best) and city, the worst.

I have read no document suggesting that but it seems the most practical approach. I doubt that it takes the advantage of using synthetic oil into account because to my knowledge there is no sensor installed to do so in the manner that there is to detect ethanol use.

So switching to synthetic probably bumps the life expectancy up a grand or two or maybe three.

[pocket-rocket]

Well I run my car hard a fair amount of the time, so I'm sure that knocks it back down a grand or three, lol.

[bszopi]

From AllData for my Alero...

GM OIL LIFE SYSTEM
Your vehicle has a computer system that lets you know when to change the engine oil and filter. This is based on engine revolutions and engine temperature, and not on mileage. Based on driving conditions, the mileage at which an oil change will be indicated can vary considerably. For the oil life system to work properly, you must reset the system every time the oil is changed.

When the system has calculated that oil life has been diminished, it will indicate that an oil change is necessary. Either a "CHANGE ENGINE OIL" message in the Driver Information Center (DIC) or a CHANGE OIL indicator will come on. Change your oil as soon as possible within the next two times you stop for fuel. It is possible that, if you are driving under the best conditions, the oil life system may not indicate that an oil change is necessary for over a year. However, your engine oil and filter must be changed at least once a year and at this time the system must be reset. It is also important to check your oil regularly and keep it at the proper level.

If the system is ever reset accidentally, you must change your oil at 3,000 miles (5 000 km) since your last oil change. Remember to reset the oil life system whenever the oil is changed.

[gpse3400]

I personaly like the TDC and TGP water cooled oil filter adapters. But since I'm keeping the AC on the beretta, Im needing something like the Caddilac oil cooler. But I think 3*00 berettas can use the TDC , TGP oil coolers if the A/C mounts like the w-body.

Also the TDC TGP ones act like a oil heater in cold winter days.

Some 3400's in the minivans and some 3100s in police spec Luminas got an oil cooler that is made specially for the GEN setup. You might wanna search there.

[gpse3400]

I ran the oil in my Monte to over 6000 miles and the DOD lifters started to clatter...I did two oil changes in an attempt to alleviate the lifter noise and it went away... Some say it was the oil I was using. Some think the oil was just dirty... One thing to think about if you run the oil for too long you don't nessesarilly get rid of all the grit in the oil...Despite the filters best protection. Changing it is the only way to get rid of most of the particles that the filter leaves behind.

The GP doesn't seem to care as it eats a quart every 2K...I seriously wonder how much longer that engine will last....188K is alot....

[TurboGTU]

I'll see if I can find a police spec Lumina.

I don't know if this is on topic or not, but if your using regular oil, then yes you would need to change it about every 3K miles. But if your running synthetic blends you can go 7K miles. It be fine if you just change the filter after 3k miles and add about a quart of oil of synthetic blend.
Full synthetics can go more.
I have used Mobile 1 15,000 mile Extended performance on the Fusion and changed the filter and add a quart every 3K miles. Im already on the last 2k miles before I need to change all the oil. Last change I had used a quart of Ford synthetic blend (real cheap) since its the last 3k miles. So using two filter to leave them on longer is bad. Had a costomer come in than hadn't change the oil for 8K miles and the cartrage filter littrally fell apart. It was CRISPY!

[Z26-T]

I've done some that the engine oil life didn't come on until around 7000 miles, but when it does come on and the oil comes out, the oil is terrible. I've done some that it looked like it was coming out a duramax, made the same black stains on my hands as the duramax. Done a couple trade ins, looked at the sticker and the customer hadn't changed it in 10k+ miles. Am I saying it was good they went this far? No. Am I saying you should go by the oil life monitor? That's up to you. Personally, I do it from 3k-5k miles, 5k with additives, 3k without, and the oil looks terrible both ways (because of how I drive, and short distance driving). I'm at 150k and the car is driven like a race car, I don't burn/leak oil, and it sounds healthy. I don't see any pluses of using dual filters. Yes, the filters remove the dirt and grit from the oil, but what about the hydrocarbons (unburned fuel) that is in the oil from normal blow by? How much "dirt" is there actually in your engine? I don't really get how large amounts of "dirt" is going to get into my engine if I change the air filter, clean the funnel, and put the oil cap/dip stick back in... The reason you change your oil is because the cleaners and detergents inside your oil start to break down after 3k miles, and are overloaded with contaminants (acids, hydrocarbons) from normal combustion.

[pocket-rocket]

http://60degreev6.com/forum/showthread.php?t=39940

That is a post I did a while back that had a site that did a study on synthetic oils. The people used various main stream synthetics and did oil sample tests to back up manufacturer claims.

[Superdave]

I've had to change my oil about 4 times since March.. damn fuel contamination


Hopefully all that is over with now that it's tuned..