Originally Posted By: Clevy
Originally Posted By: Ducman
Originally Posted By: Clevy
Originally Posted By: RISUPERCREWMAN
Amsoil does nothing better that I can't get at Walmart for much cheaper with no shipping costs. IE Mobil-1 Extended Performance or Royal Purple. I change my oil when the oil life computer tells me to. Anybody who runs Amsoil for 25K mile service interval in an engine needs to see a psychologist.
Well I agree with the first part about the Walmart comment however if Amsoil really can go 25000 miles why not run it out that far.
Everyone I know who runs extended intervals with Amsoil ends up needing to add oil at some point during the interval. Enough top ups would re-additize the sump and raises the tbn which could very well mean the oil can go that 25000 mile advertised interval.
No way would I run the oil 25000 miles if no top ups though.
Precisely.
Periodical top ups can make quite a big difference to the long term outcome.
I believe, that's why when running a Frantz bypass filter and changing the filter element at the recommended intervals, it's actually possible to push out the OCI's to the >100,000 mile region in some engine applications.
As an example of what's possible.
I have UOA's from one particular engine with a 3.7 l oil capacity, that verify the difference in the oil's reserve with a single small 200 ml top up over a given OCI, and with a total of 3x larger top up quantity over the same OCI.
The actual difference between the UOA's is staggering in terms of the oils life span.
Those franz filter systems are awesome. A friend of mine has been running one since the mid nineties on his cummins and when he trades in the truck he gets it installed on the new one he buys.
He gets uoa done and his oci tend to be every 50000 miles or so.
He changes the TP roll every 10000 miles and tops up the system.
With that kind of system the oil change interval could almost go indefinitely.
Yes, it could almost go indefinitely when supported by UOA's.
I think the only thing one would have to be concerned about would be the relationship between TAN and TBN in the longer term.
If I remember correctly.
They used to recommend changing the TP filter element every 2000 kms.
Just for giggles, I did an experiment with an old worn out/badly neglected 4.1 litre 6 cylinder passenger car engine, that was very seriously sludged back in the mid 80's, just before a full rebuild.
In some parts of the engine the sludge was actually about 3/4" thick before the rebuild.
I'd often seen the filters at the car shows, and was always curious as to how good they really were. Or whether it was snake oil stuff.
I figured the test engine was a good candidate to find out more about its effectiveness.
I did an oil change on the engine and refilled with some cheapo 15w-40 diesel engine oil and fitted the Frantz filter.
I drove the car as usual(which was mercilessly) for about another 1000 kms before yanking the engine out to rebuild it.
The difference on tear down was absolutely mind blowing, as there was virtually no sludge to be found in even the most far flung and remote regions of the engine where there was typically very little oil flow.
That result opened my eyes up to possibilities of using a bypass oil filter system of some description.
Needles to say I consider a significant part of the experiment was a success.
Seeing pics posted on this good forum of engines which people consider to be sludged.
I think to myself all they need to do is fit a Frantz filter and change the element at regular intervals then top off the oil level as required.
Problem solved.
