This forum has a lot of good information about the performance of motor oil and what may be behind it. Many have a favorite oil and some even have an oil in mind that they do not like. We all talk about used oil analysis, oci's, tbn's, filters, additives and the like. I have been digging through a lot of data on vehicles that are used in severe duty and what has been done to get the best service out of these vehicles beyond, careful operation, maintenance practices, fluid specs and other considerations. I spend time on the phone today with a couple of the mechanics and some of the supervisors and have come up with a common thread for improved survival of the engine itself in such operation. Once you've got good oil and filtration and maintenance the single best modification to support such service is increase oil sump capacity. In situations where I can isolate it, sump capacity is more important than synthetic oil. The one thing that the sump capacity helps is not clean oil, but a clean engine. It's the clean engine that makes the difference and the sump helps keep the junk in the oil where it belongs. We have had oil from one of these large sump vehicles that is loaded with junk and the engine itself is clean and running well even though the engine is working in terrible heat and pulling a big load, day after day. It also looks like Auto-Rx and a great big sump could be the magic bullet we are all looking for. As good as Auto-Rx is with a standard sump, it’s even better with the larger capacity and points to the idea that it’s the clean engine that makes the difference, not clean oil. We think it’s so important that the 12 new light duty gas powered trucks we are putting into service are getting large oil pans. We are dealing with a couple of vendors that may in the future be offering larger pans for service vehicles and hope to have some pictures. Anyhow, I just though I would post my thoughts and see what you have to say.
I'd like to make a statement about motor oil
- Thread starter Lonnie
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Lonnie, I could not agree with you more. The best example is the oil capacity of a class 8 truck. Those things don't hold 14 gallons for nothing. No way they get the miles they do without this capacity.
Good call
Good call
Agree with the capacity comment. Often overlooked. As for those 12 light duty trucks, depending on the difficulty of replacing and cost of the oil pans, it might be easier and cheaper to install a large remote filter and oil cooler. Just a thought.
So using bigger oil pans is how you're getting the increased sump capacity. I guess there's no clearance problems due to the larger oil pans.
On an old car of mine ('99 Civic Si w/B16A2) I used a larger Moroso oil pan and consistently saw a large temperature difference on track over the stock pan. IIRC it only added like 1.3 quarts of capacity but that was close to 125% of the original capacity. It wasn't a completely scientific test but I was always happy to have the extra breathing room temperature wise.
Jon
Jon
interesting thought. thank you for sharing lonnie, i never considered that before. it makes sense if you think about it.
Anytime that you can use a larger filter, it definitely helps both in increased filtering capacity, and a little more oil is circulating in your engine.
I have a motorcycle with a 2053 cc watercooled V-twin engine, and it holds 5.8 quarts. That's more than any car I've ever owned. Maybe that will help it stay cleaner.
more sump capacity seems like a no brainer. the oil has longer to cool off while sitting in the sump, any wear particles are diluted (and cause less wear since they circulate less), and any fuel dilution problems are reduced.
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My wife's Mercedes holds 8.5 qt's of oil, and Mercedes says I can expect to go approx. 12k miles between changes. I could never go that far, though.
What about the short trip in cold weather type of "severe service". It seems to me that if the total capacity is increased in a situation where the oil is not always getting warmed to noremal operating temperature before shutting down, it would only worsen the problem.
On the other extreme, GM put a small sump and filter, 4qt + 1pt, on my 4.3L V-6 pickup and then added an external oil cooler. It would seem that more oil and filter size would be a lot cheaper to build.
On the other extreme, GM put a small sump and filter, 4qt + 1pt, on my 4.3L V-6 pickup and then added an external oil cooler. It would seem that more oil and filter size would be a lot cheaper to build.
Can see how the expense of buying/installing a larger oil pan might be beneficial for a fleet of vehicles, especially if getting them in for scheduled service is an issue. IIRC though, you are big on services of about 5K OCI so you can check over the vehicle thoroughly, anyway.
If the vehicles are going to get in every 5K, I'd be suprised if there was a payback on your investment.
On a personal vehicle, a remote filter and/or oil cooler would be the most trouble/expense that I'd consider.
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If the vehicles are going to get in every 5K, I'd be suprised if there was a payback on your investment.
On a personal vehicle, a remote filter and/or oil cooler would be the most trouble/expense that I'd consider.
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I've been running six quarts of oil with an oversize filter in my Buick's stock oil pan (that specs 4.5 quarts) with no problems what-so-ever. I'm thinking that some of these manufacturers may engineer an allowable amount off extra capacity into their oil pans that the owners may not know about.
Besides the cooler steady-state temp, how is a bigger sump capacity any different than just changing oil more often?
If I could change only one thing in an effort to reduce wear, I would increase the oil flow rate by increasing the oil pressure. (But this would wear out my oil pump sooner.)
If I could change only one thing in an effort to reduce wear, I would increase the oil flow rate by increasing the oil pressure. (But this would wear out my oil pump sooner.)
The little 2.5L I4 in my Ranger holds a full 5 quarts, which is more than most four cylinders. Maybe it is coincidence, maybe not, but these engines are known as one of the most reliable Ford has ever built. I'll need to look into an even larger oil pan for it. I know they make them, but I think they are intended for Mustangs and Thunderbirds mostly.
I agree, changing the oil more frequently could in effect accomplish the same thing. But in a large fleet situation more frequent oil changes may not be a realistic option.
The remote filter/oil cooler was mentioned as the limit of what I would consider to increase the sump capacity of my personal car. And then only because of the additional benefits of slightly better filtered oil and reduced temperatures.
Regardless, I'm gonna stick with changing my modern conventional oil every 5K. It sure has worked for me over the years.
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I wouldn't increase the sump size unless it was obviously too small. Even then, I might just run high end synthetic which should give all the benefits (and much more) of a larger sump with conventional.
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