8.1 oil change...how many quarts? throw a dart

[F4Gary]

Originally Posted by davebw31

Oh Nooooooooooo, you using a Wix filter? Throw that in the garbage. If you knew the "particulates rating or Microns" and what the "by-pass valve pressure is rated at" you will never use a Wix, NAPA, Fram, or any other "cheap" filter.


I know something about filters and oils. I was the fleet manager of the fourth largest school bus fleet in the USA.


In the motor home I use the Delco 2 qt. filter. In everything else I use Luber-Finer, Baldwin, Motorcraft, Mobil 1, and Honda filters in my car. They all have 14 lb. rated by-pass valves, some with anti-drain back feature, and are a minimum 5 Micron filtration. The point is don't cheap out on oil filters. Most of the cheap filters have a 20-25 lb.by-pass valve and only 10 Microns filtration! When we were using 10W30, 10W40, or 20W50 oils these filters were just OK. We are now using 0W5, 0W10 and 0W20 oils that flow differently and need lower by-pass pressure valves and better filteration.

BTW: I periodically send my oils out for testing and ever so often I cut open the filter to check for metal particles. The report says "continue use", however I still change all vehicle oils at 5,000 miles

Sorry, but this is outdated info. Go read Bobistheoilguy.com.
The best oil filters now are Fram UltraGuard, Mobile 1, Wix/UltraGuard, and Royal Purple.

[tmw188]

The dip stick is easy to read on my motor. Just start with 6 qts. and go from there.

[Forkyfork]

Originally Posted by Moesbro

Oops, My original math was off, those jugs of oil are 5 qts, not the gallon I was assuming. So, it was actually about 8 qts. of oil to slightly over fill it with the 2 qt. filter. I had also always heard that Wix filters were good quality. Running Castrol GTX 10w-40 btw, in case anyone wants to shoot that down too. 😎

Im sorry. I know you are feeling a bit of flack here. Maybe its a typo but the 8.1 calls for 5-30, 10-30 can be run if you aren't driving it in a colder environment.

This is the service guide and has all the lube points by chassis.

http://deserttruckservice.com/pdf%20...ssis.guide.pdf

[tmw188]

Yes I don’t think 10w-40 is recommended. I almost purchased that wt. until I looked in the manual.

[Forkyfork]

I think the oil weight is on the oil cap or somewhere in the engine compartment. We were able to figure it out without the manual.

FWIW these engines consume oil. Keep some on hand you can possibly need to add 1 qt oil every other tank.

[tmw188]

Originally Posted by Forkyfork

I think the oil weight is on the oil cap or somewhere in the engine compartment. We were able to figure it out without the manual.



FWIW these engines consume oil. Keep some on hand you can possibly need to add 1 qt oil every other tank.

It is on the cap 5w-30 but other options are given and yes about the consuming oil. I was just talking about that today. When I’m traveling and towing I will go thru 1qt in about 800-1000mi. I carry enough oil for the trip at hand or buy a qt if boondocking at WM. I may try petroleum based oil next tine to see if there would be a difference but think it could be worse.

[vettenuts]

The original reason I saw cited for not using a #W40 oil was sticking of the rings. However, oils have change a lot in the last 12+ years. The marine version of this engine uses a heavier oil. I recently went to the Mobil-1 European 0W40 oil because it meets the European requirements and the viscosity at 100 degrees C is barely out of the 30W viscosity range (it is a very light 40W oil).

[Forkyfork]

Originally Posted by tmw188

It is on the cap 5w-30 but other options are given and yes about the consuming oil. I was just talking about that today. When I’m traveling and towing I will go thru 1qt in about 800-1000mi. I carry enough oil for the trip at hand or buy a qt if boondocking at WM. I may try petroleum based oil next tine to see if there would be a difference but think it could be worse.

I suspected it and then found this in the service manual which confirms that it is expected. Its possible that the engines that fail due to oil starvation weren't kept topped off.

Measurement of Oil consumption: Engines require a period of time to BREAK IN so that moving parts are properly seated. erefore, oil economy should not be tested until the vehicle
has accumulated at least 8000 km (5000 mi) and the oil has been changed for the rst time. Manufacturers of piston rings state that piston rings in today’s engines, control oil very e ectively. For example, if 1/10th of a drop of oil would be consumed per explosion when driving at 60 MPH, an eight-cylinder vehicle would use about 90 quarts of oil on a 600-mile trip. e actual average consumption of oil per explosion in today’s engines is from 1/1,000th to 2/1,000th of a drop.
Oil consumption is often more related to duty cycle than mileage. A good GM guideline is one quart per 100 gallons of fuel used.

[Mudfrog]

I thought I had read this before in my manual so looked today to verify. It states in bold text,

"Do not use SAE 10W-40, SAE 20W-5 or any other any other grade oil not recommended".

This on my 2003 8.1.

As far as oil usage, ours has never used any between changes. Honestly, I wouldn't keep it if it used a quart every 1000 miles.

Like others, a bit over 6 quarts fills it to the mark at the change. Dino 5W-30 and a Fram filter do the trick. And before you cringe, I've been using this combination for over 40 years and never had a single issue.

[harleyjt]

You wouldn’t use a Fram filter if you cut one open and saw how it’s made compared to others.

[harleyjt]

Originally Posted by Forkyfork

I suspected it and then found this in the service manual which confirms that it is expected. Its possible that the engines that fail due to oil starvation weren't kept topped off.



Measurement of Oil consumption: Engines require a period of time to BREAK IN so that moving parts are properly seated. erefore, oil economy should not be tested until the vehicle
has accumulated at least 8000 km (5000 mi) and the oil has been changed for the rst time. Manufacturers of piston rings state that piston rings in today’s engines, control oil very e ectively. For example, if 1/10th of a drop of oil would be consumed per explosion when driving at 60 MPH, an eight-cylinder vehicle would use about 90 quarts of oil on a 600-mile trip. e actual average consumption of oil per explosion in today’s engines is from 1/1,000th to 2/1,000th of a drop.

Oil consumption is often more related to duty cycle than mileage. A good GM guideline is one quart per 100 gallons of fuel used.

Seems a bit much. On average in my coach that would be a quart in 700 miles. That would be unacceptable to me. I have always subscribed to a quart in a thousand.
Jt

[Forkyfork]

Originally Posted by harleyjt

Seems a bit much. On average in my coach that would be a quart in 700 miles. That would be unacceptable to me. I have always subscribed to a quart in a thousand.
Jt

Just posting what workhorse put in their maintenance guide. I didn’t write it.

My point being. Check the oil regularly because it is normal to have to add some in between changes.

[Forkyfork]

Originally Posted by harleyjt

You wouldn’t use a Fram filter if you cut one open and saw how it’s made compared to others.

They don’t need to. Plenty of youtubes and blogs already have.

[Mudfrog]

Originally Posted by Forkyfork

They don’t need to. Plenty of youtubes and blogs already have.

Actually, I have opened one up and saw nothing to be concerned about. Seems kinda strange that some people go on about how junky these filters are, yet the company continues to be a mainstay in the filter business. Not trying to be a wise guy but,, do any of you know for a fact that a Fram filter "itself" caused the death of an engine? If yes, then what criteria did you use to come to that assumption?

As I said above, i'm going with actual experience, over 40 years worth. I'm not looking at videos on the web or reading someone's, most likely, biased opinion.

Heck, not sure why I'm even posting here as we all know we have our opinions that won't be changed.