TP Change Interval Analysis

[acewiza]

Here's a pic of the cut open TP from a 6,000 mile run off a 5.2l Magnum v-8 in a 2000 Dodge 1500 Ram pickup. Ignore the obvious specs around the front and bottom. That is just dirt from sitting under the workbench for a couple days. I was hoping some more telling knowledge could be seen after draining for awhile:

http://66.17.171.114/PhotoAlbum/Cars/Pics/1500_01.jpg

We went on a ~1,800 road trip vacation last week. The MG was due for a change, but it was still flowing and I was behind the power curve for getting ready, so I left it in there just to see what would happen. Any thoughts?

It was still flowing (getting hot) with almost 6,000 miles on it. My guess would be this is just a clean-running engine that can go quite awhile on a roll of TP. I think this goes well towards supporting the notion that TP is not all that limited in terms of endurance, as some naysayers in the forum here seem to keep claiming. I see no reason why a good running smaller engine coudn't do 10k miles on a roll of TP.

 

[johnd]

I think your judgment is on the money but I'm surprised at the long interval. I was sitting here wondering whether to change mine at 2000, 2500 or 3000. Maybe the temperature evaluation would, indeed, be the way to go.

 

[Gary Allan]

quote:

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I think this goes well towards supporting the notion that TP is not all that limited in terms of endurance, as some naysayers in the forum here seem to keep claiming. I see no reason why a good running smaller engine coudn't do 10k miles on a roll of TP.

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This may surely be true in some applications, under some conditions. However you would be throwing out the "perpetual sump" aspect of tp filtration if you did so. You can't run 10k and put in another roll and top up and continue to run.

Now if you're just looking for fine filtration and have no intentions of retaining the sump, then sure.

As I've said in another post, it would be nice if there was a cheap lab to do just PC. You could then just do PC starting at 3k and see where the particle count starts to climb. You then determine where your cost/benefit crossover occurs.

 

[sifan]

acewiza - How long has the oil been in your engine? I agree with johnd that your TP change interval is too long expecially with a V8 eninge.

The M1 5W30 oil in my '03 Toyota Echo (4 cylinder engine) has seen 30k miles. I change the full flow oil filter every 18k miles and TP every 3k miles with 1 qt of makeup oil. Due to the way I drive it like an old lady to conserve fuel and reduce engine wear, the engine (52k miles on odo) suffers carbon deposit related issues despite the use of Techron and Sea Foam Deep Creep every 1k~2k miles for the last 20k miles. I notice the my used TPs are especially dirty like the one shown in the photo in the winter even with 3k miles. As the oil stays longer in the engine I should reduce the TP change interval from 3k to 2k or 2.5k miles.

I will install the pre-oiler to my Echo soon which reqires full oil drain. I am thinking afterwards to keep TP change interval to 3k miles while doing full oil drain and full flow oil filter replacement every year (18k miles per year). Or I might use dino oil instead and do the whole routine every 3k miles to alleviate the carbon deposit problem in the engine.

I am not so sure about infinitive OCI with oil bypass filter. Maybe the bypass filer should be used as a supplement filter along with the factory full flow filter with regular OCI.

 

[acewiza]

That was the 1st MG change on this OCI, 1k late. Truck is running M1 TSUV 5w40. It has about one and half quarts of makeup and topoff and a fresh roll of TP in it at this point. I am shooting for 15k OCI with 2 MG changes at 5k ea. I had a 10k UOA from another vehicle with 2 MG changes at ~4k, which showed plenty of life left in the M1 10w30 EP it was running at the time, so this seems reasonable. I will do a UOA at 10k after the next MG change to confirm the hypothesis. Perpetual sump is not the goal on these, just long OCI and TP change interval determination.

This motor normally gets run very hard. WOT for periods of a minute or more towing up hills, running through the mountains around here (again WOT to maintaining speed on steep grades), and cruising down the Interstate at 75mph, literally all day long. Amazingly, it got 19mpg one day driving in Yellowstone last week. That was the only break it got the whole time, just loafing along in 4th or 5th gear at 30-50mph. It now has 115k miles on it and runs better than new.

[ September 07, 2006, 07:19 PM: Message edited by: acewiza ]

 

[SWHeat]

I'm confused. Other than doing the perpetual sump idea....why would you need to change the TP in a V8 (or any other engine) at 2K, 3K or 4K if it is still flowing?

 

[unDummy]

Trasko's can last 10k miles for a 1/2 toilet roll.

If not changing oil regularly, TBN drop can be an issue even if the filter is still filtering.

I guess the 3k recommended TP change interval is to help prevent issues from TBN drop for those using a weak oils, for those NOT using TBN boosting additives, or not practicing UOAs.

 

[Gary Allan]

quote:

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Originally posted by SWHeat:
I'm confused. Other than doing the perpetual sump idea....why would you need to change the TP in a V8 (or any other engine) at 2K, 3K or 4K if it is still flowing?

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There is no need to change it if it is still flowing if you are going to swap out the oil at some point anyway. Many oils by themselves will make 15k without difficulty. A TP bypass will just add a higher level of filtration.

 

[acewiza]

Exactly, Gary. You think 20k with 3 5k MG changes and a full-flow change at halfway is in the cards? Might that constitute enough makeup oil over that period for a good premium syn like TSUV?

The point to this post was to refute the oft bandied about rhetoric I've seen around here that goes something lke this: "TP filters great but you have to change it very frequently so you end up spending more time and effort with it, plus adding more oil so it is really not that great a bypass solution."

WRONG.

Concerning the pic I posted, it looks to me like there is a very slightly more darkening towards the top, which seems to indicate there is plenty of life left in this filter, with 6k miles on it running in a V8 engine. Anyone agree?

 

[unDummy]

I agree. Just remember to verify TP temp or flow prior to jumping to the 'never change TP again bandwagon'.

In the UOA section, there are plenty of ~10k+ runs with nothing but a full flow filter. Newer engines & oils are just that much better. But, driving style needs to be considered.

If you want to run the TP for a full 10k OCI, and are still practicing OCIs, I don't see the need for 2-3 TP changes.

Don't forget that driving style will also affect the situation. For example, one member, with a timer, drives 10k all highly miles in 250hrs. I used my stopwatch for about a month and calculated 3k miles, mostly city driving, in the same ~250 hours. A timer is more eye opening then the odometer.

But, if you NEVER want to change the oil again, I'd agree with the 2K-3k roll change interval.

 

[acewiza]

I haven't actually settled on any specific approach ATT. The only thing I have determined for sure at this point is it will end up varying somewhat from one vehicle to another in our little fleet, depending on things like you mention above, driving style, among others. Just testing ideas and trying to find a combination of cost effective, efficient and high quality service, but at the same time "low maintenanece" methods. Gotta have that cake and eat it too, if at all possible!

 

[Gary Allan]

quote:

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Originally posted by acewiza:
Exactly, Gary. You think 20k with 3 5k MG changes and a full-flow change at halfway is in the cards? Might that constitute enough makeup oil over that period for a good premium syn like TSUV?

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Your only limit, imo, is if the oil itself can carry the OCI. Something like RTS or TSUV (anything with a high initial TBN) will probably manage if the miles are long enough. You probably need to put a time/mileage limit to it for practical purposes. Something like 1 year max. If there's no shearing problems ..then the tp filters should keep deposits well in check ..or so I'd reason. I would also reason that if your oil is shot, and producing more nasties, that you would see your tp filter starting to shorten in life span.

I'm waiting for XS650's OLM comparison to TooSlick's OCI fuel calculation. Ted has a formula back constructed from empirical data. All you have to do is record fuel usage (or accurately track your mpg). This type of reasoning, more or less, combines and odometer and hour meter into one factor. Fuel consumption takes just about everything into account. Idling, long trip, short trip.

 

[mjo]

quote:

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Originally posted by sifan:
Due to the way I drive it like an old lady to conserve fuel and reduce engine wear, the engine (52k miles on odo) suffers carbon deposit related issues despite the use of Techron and Sea Foam Deep Creep every 1k~2k miles for the last 20k miles.

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Sifan, a "PCV catch can filter" would surely help in reducing the carbon buildup. You could just dump the oil collected from the catch can back into the engine and your TP filter would clean it up. Good luck with the preoiler.

 

[sifan]

Thanks. I recently installed an AMW PCV catch can, but, I wish I had done that sooner. However, the catch can does not prevent PCV from being clogged up by oil. I used to replace PCV every 12k miles. But, now after only 9k miles the engine starts to idle a bit roughly. I notice smooth idle returns after PCV replacement.