synthetic oil change intervals

[dpuckett]

MY girlfriend works at a local automotive repair shop. We were discussing oil change intervals one day (specifically diesels, as she was given the task of writing a pamphlet for general maintenance to give new owners), and she said her boss claims you can go 2-3x as long with synthetics as you can with straight dino oil. I asked if they were installing a bypass system or some other filter to go with the extended drain intervals. "No, the synthetic oil lasts much longer than regular oil, and that's why you can go longer on chnages. " Or that's what the boss says.



I contend that extended drain intervals should only be used if you have a bypass system, and/or use oil analyses to tell when the oil is being depleted of additives. The oil change is only as good as the oil and filter you use. Going 10-15K mi when you should be changing the oil every 5K is asking for early engine wear.



So, who is right? Or at least closer to right? And why? I'd like to present a good argument to him if/when I decide to defend my point of view.



Daniel

 

[JCasper]

Show him this, no bypass. Enough said.



https://www.turbodieselregister.com...ns-2003-2007/193501-oil-analysis-results.html

 

[amsoilman]

MY girlfriend works at a local automotive repair shop. We were discussing oil change intervals one day (specifically diesels, as she was given the task of writing a pamphlet for general maintenance to give new owners), and she said her boss claims you can go 2-3x as long with synthetics as you can with straight dino oil. I asked if they were installing a bypass system or some other filter to go with the extended drain intervals. "No, the synthetic oil lasts much longer than regular oil, and that's why you can go longer on chnages. " Or that's what the boss says.



I contend that extended drain intervals should only be used if you have a bypass system, and/or use oil analyses to tell when the oil is being depleted of additives. The oil change is only as good as the oil and filter you use. Going 10-15K mi when you should be changing the oil every 5K is asking for early engine wear.



So, who is right? Or at least closer to right? And why? I'd like to present a good argument to him if/when I decide to defend my point of view.



Daniel

Amsoil Heavy Duty Diesel & Marine (AME) 15W-40 Engine oils, which are PAO based, have a recommended drain interval of up to 25,000 miles/one year.



However, they only recommend the 25K/One year intervals if used in "Personal" transportation vehicles frequently traveling greater than 10 miles and not operating under "Severe Service"



Severe Service is defined as: Extensive idleing, daily short trip driving less than 10 miles (16km), frequent towing, plowing, hauling or dusty conditions.



In "Severe Service" conditions, the recommendation is 15K/one year.



Modifications such as JCasper has done are also excluded! His truck is using a modified fueling system, so he is adding more fuel that results in incomplete combustion, therefor increasing soot that contaminates the oil.



These figures are found on the amsoil website.



Wayne

 

[JFaughn]

I found that many things have to be on a one by one basis , like mentioned above , how is the truck set up & running is the biggest .
The last 3+ yrs , I have been running standard Rotella 15/40w , analysis from 2 different companies [ Blackstone & Cummins ] have both said that at 11,000 + , I could go longer .
I have been using Donaldson , Amsoil , Wix and Napa Gold [ same as Wix ] , using filters with known good rep .
I want to add a centrifuge oil filter or by pass system .
But like any work being done , do the testing to see what you need , analysis .
I forgot to mention that I have switched to the Amsoil mentioned above , want to do an analysis [ because I have been hearing & reading about questionable results after switching , maybe doing some washing/flushing , then if results are ?able , do a change of of the Amsoil [ same ] and see if test results clear up .

 

[JOdell]

I just used changed my oil at 1 year and 18,000 miles. I do light to moderate towing about 30% of the time. I had my oil tested all my numbers were better than the standard 5,000 changes with regular oil. I know this comes from a Dealer. But I back up what says. It is all on how you run your truck. And the maintenance preformed. -Jason

 

[Vaughn MacKenzie]

Without sampling, I wouldn't run any oil past 10,000 miles. With sampling the Amsoil & other top-shelf synthetics are good for a lot more miles than dino oil due to the additives.

With my 2001 I ran 20,000 mile intervals without bypass filtration, sampling every 10k, and the oil did great. Iron count was usually in the 40s after 20,000 miles.

Vaughn

 

[nickleinonen]

i change my oil 2x a year. . not based on mileage. . i run synthetics because of the "severe service" i drive



[my truck should roll over 60,000km this week - delivered oct/03]

 

[JOdell]

Without sampling, I wouldn't run any oil past 10,000 miles. With sampling the Amsoil & other top-shelf synthetics are good for a lot more miles than dino oil due to the additives.



With my 2001 I ran 20,000 mile intervals without bypass filtration, sampling every 10k, and the oil did great. Iron count was usually in the 40s after 20,000 miles.



Vaughn

Vaughn, I agree with you sampling is very important. I have a customer that runs a 05 Pete with a Cat motor. He has run AMSOIL for 70,000 miles and hasn't changed it. That is wicked crazy. Now the twist. He runs a Gulf coast bypass filter. Every 10,000 miles he changes the 2 filters in that and the full flow filter. He also takes a sample and sends it in. When changing the filters out he has to put in 2 1/2 gallons of oil in to replace the oil lost in the filters. He basis his oil changes on recommendations from the sampling company. -Jason

 

[JCasper]

Modifications such as JCasper has done are also excluded! His truck is using a modified fueling system, so he is adding more fuel that results in incomplete combustion, therefor increasing soot that contaminates the oil.



Wayne

That's me.



Wayne you are very much right and I probably should of not been lazy and when I added the amsoil I should of added Bypass.



I have been an amsoil dealer for about 5 years and have run synthetics in everything. I however was skeptical about running it in this truck due to my short 4 mile trips to work, extensive idling, and not getting warmed up on a lot of trips. Although on those short trips my truck is empty (No load) it is still what I would call very Severe service.



I am going to run a normal dino oil for the time being and shorten my OCI due to my type of driving. I will however continue to run Amsoil in everything else and everywhere else on my truck except for the motor.

 

[amsoilman]

That's me.



Wayne you are very much right and I probably should of not been lazy and when I added the amsoil I should of added Bypass.



I have been an amsoil dealer for about 5 years and have run synthetics in everything. I however was skeptical about running it in this truck due to my short 4 mile trips to work, extensive idling, and not getting warmed up on a lot of trips. Although on those short trips my truck is empty (No load) it is still what I would call very Severe service.



I am going to run a normal dino oil for the time being and shorten my OCI due to my type of driving. I will however continue to run Amsoil in everything else and everywhere else on my truck except for the motor.

With the type of driving you do, I would consider a by-pass! Considering you're a dealer, you wouldn't be spending that much to get one.



I've got nearly 5 years and 65,000 on the same change using the Amsoil by-pass with oil analysis done every 10,000. Last analysis showed 0. 7% soot/solids.

 

[Skydiver]

Change LF3552 every 5k.

Change Rotella Synthetic every 10k.

Run oil analyisis every 20k.



No problems.