Regulars probably know I own a towing company and a full service repair facility.
Had a young man come in with his father with a new-to-him Chevy 2500 with a Duramax—need brakes all the way around. Suggested an oil and fuel filter change bc the OLM was indicating due and since they bought it used and had no maintenance records suggested doing fuel filter with the oil change. They declined my suggestions because they told me they had just ordered an oil filter adapter plate for the Duramax enabling them to use a Caterpillar oversized filter.
https://mddperformance.com/products/cat-oil-filter-adapter-kit
This allows the use of a 1R-1807 on the Duramax. The father and son believed the factory filter and oil quantity was undersized.
I strenuously advised against this modification for the following reasons:
—stick with OEM / Duramax 6.6 has been on the market well over a decade, I can't remember exactly, but we are probably if not at then very close to 15 years of production now. Never once has GM, despite other upgrades, changed the capacity of the oil pan or increased the filter size. I would give the D-Max "Work-Horse" status. It's been a great engine. There is simply no data or anything to indicate the oil capacity or filter is undersized. None.
—after a quick Google search the Cat 1R-1807 has no anti-drain back. The positioning of the filter housing means oil can and will drain back out of the oversized filter leading to reduced oil at start—which is proportionally where most engine wear occurs.
—although I have no direct oil filter studies I can find to substantiate this....there is empirical evidence from multiple types of different filter media that dirt attracts dirt. In other words, it well known a slight dirty or dirty but not to capacity filter be it water, air, vacuum cleaner....anything.....is more efficient than a virgin new or lightly loaded filter. Filters filter best once collecting dirt. In my opinion, over-sized filters although providing more filter area actually are less efficient overall because of the above dirt attracts dirt effect.
—The truck had around 225k miles. I suggested at this age and mileage any possible benefits (which I don't believe there are any benefits) would be too little too late at the truck's age and mileage. Knowing the father and son as regular clients and knowing he was saving up for this truck and money is tight I assured them the better spent money would be doing a full maintenance on the truck of all fluids I.E. oil, filter, fuel filter, transfer case, differentials, transmission and coolent. The previous owner did not have any maintenance records.
They left very confused but I'm hoping they cancel the oversized filter kit. The only reason I can ever See an oversized filter being beneficial is if running extreme OCIs. Even extended OCIs are no problem for OEM sized premium filters like M1, Ultra, Royal Purple ect. I think to oversized a filter would take a very specialized operation maybe like mining where you run 24/7 for a said duration and the only time maint could be accomplished was using a shut down of the operation.
What say you? Boards have been slow so I figured this would be a good discussion topic.
I also directed them here to the "Bobber's". Finally, the family has been a long time client of my shop and I offered to do a free pre-buy inspection before they signed the deal. Just to muddy the waters I suggested a gas truck for the son and not diesel but boys will be boys I guess. I also suggested a Ford 6.7. I think the Duramax is a good engine but my experience has proven for my use the Fords hold up much better IMO.
They got overly excited and bought this truck without taking advantage of my free inspection offer. IMO a mistake but hope it works out for them. They are good peoples.
Had a young man come in with his father with a new-to-him Chevy 2500 with a Duramax—need brakes all the way around. Suggested an oil and fuel filter change bc the OLM was indicating due and since they bought it used and had no maintenance records suggested doing fuel filter with the oil change. They declined my suggestions because they told me they had just ordered an oil filter adapter plate for the Duramax enabling them to use a Caterpillar oversized filter.
https://mddperformance.com/products/cat-oil-filter-adapter-kit
This allows the use of a 1R-1807 on the Duramax. The father and son believed the factory filter and oil quantity was undersized.
I strenuously advised against this modification for the following reasons:
—stick with OEM / Duramax 6.6 has been on the market well over a decade, I can't remember exactly, but we are probably if not at then very close to 15 years of production now. Never once has GM, despite other upgrades, changed the capacity of the oil pan or increased the filter size. I would give the D-Max "Work-Horse" status. It's been a great engine. There is simply no data or anything to indicate the oil capacity or filter is undersized. None.
—after a quick Google search the Cat 1R-1807 has no anti-drain back. The positioning of the filter housing means oil can and will drain back out of the oversized filter leading to reduced oil at start—which is proportionally where most engine wear occurs.
—although I have no direct oil filter studies I can find to substantiate this....there is empirical evidence from multiple types of different filter media that dirt attracts dirt. In other words, it well known a slight dirty or dirty but not to capacity filter be it water, air, vacuum cleaner....anything.....is more efficient than a virgin new or lightly loaded filter. Filters filter best once collecting dirt. In my opinion, over-sized filters although providing more filter area actually are less efficient overall because of the above dirt attracts dirt effect.
—The truck had around 225k miles. I suggested at this age and mileage any possible benefits (which I don't believe there are any benefits) would be too little too late at the truck's age and mileage. Knowing the father and son as regular clients and knowing he was saving up for this truck and money is tight I assured them the better spent money would be doing a full maintenance on the truck of all fluids I.E. oil, filter, fuel filter, transfer case, differentials, transmission and coolent. The previous owner did not have any maintenance records.
They left very confused but I'm hoping they cancel the oversized filter kit. The only reason I can ever See an oversized filter being beneficial is if running extreme OCIs. Even extended OCIs are no problem for OEM sized premium filters like M1, Ultra, Royal Purple ect. I think to oversized a filter would take a very specialized operation maybe like mining where you run 24/7 for a said duration and the only time maint could be accomplished was using a shut down of the operation.
What say you? Boards have been slow so I figured this would be a good discussion topic.
I also directed them here to the "Bobber's". Finally, the family has been a long time client of my shop and I offered to do a free pre-buy inspection before they signed the deal. Just to muddy the waters I suggested a gas truck for the son and not diesel but boys will be boys I guess. I also suggested a Ford 6.7. I think the Duramax is a good engine but my experience has proven for my use the Fords hold up much better IMO.
They got overly excited and bought this truck without taking advantage of my free inspection offer. IMO a mistake but hope it works out for them. They are good peoples.
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