Changing my oil too infrequently? PCV problem?

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Originally Posted By: MParr
I’ve used quiet a bit of Pennzoil and the brown baked on coloration is typical. Just look at the oil as it comes out of the bottle. If you like using conventional oil, switch to Valvoline, Motorcraft or Havoline. Change out the pvc valve and plumbing.

This truck used to see 10-12,000 miles of highway only miles annually. It was pretty much only driven on the highway for the first 50k or so. Then engine was spotless until I started regularly short tripping it. I've been keeping it on synthetic because I thought it would be better for severe service like this engine sees. I think the question now is, would I be better off with a cheap conventional and changing it more often? Every 100 hours would be every 3-4 months for me, but not very many miles. I've thought a lot about how I should be determining my OCI, besides regular oil analysis. Some people use hours, others use fuel consumed. The following quote is from another thread:

Originally Posted By: babbittd
Originally Posted By: oiltard
If I cruise at 60 for an hour (to make the numbers simple) vs. sitting in stop and go traffic for an hour and only going 10 miles, the mileage formula treats the latter as being 1/6th as much a factor in oil life usage, whereas the time formula at least treats them equally.


Very interesting.

http://www.government-fleet.com/article/...ive-idling.aspx

According to research by Ford Motor Company, one hour of gasoline engine idle time equals 33 miles of driving.


Lets assume that one hour of idle time equals 33 miles of driving, and that our average in motion speed is 33mph.
Lets also assume that under normal intended operating conditions my truck would average 18 MPG.

On my last OCI I went 185H, 2,559 miles, 201.2 Gallons burned, 13.8 MPH avg speed, 1.08 GPH avg.

Assuming that my average in motion speed is 33 MPH and that 1 Hour of idle time = 33 miles of wear:
My truck spent:
41.82% of it's run-time in motion, 77.37 hours, burned 142 gallons of fuel (1.83 GPH)
58.18% of it's run-time at idle, 107.63 hours, burned 59.2 gallons of fuel (0.55 GPH)

So according to the Ford data, my oil had 2,559 actual miles on it and 3,552 equivalent miles of idle time wear on it. This means that my oil had the equivalent of 6,111 miles of wear on it.

Another way that some people say you should determine your OCI is by the fuel consumed. My truck is rated to get 18/21 MPG(19.5 combined). Toyota states a 5,000 mile/6 month OCI.
5,000/18= 277.78 Gallons (1.83 GPH) (Assuming 33 MPH)
5000/19.5= 256.41 Gallons(1.69 GPH) (Assuming 33 MPH)
5,000/21= 238.1 Gallons (1.57 GPH) (Assuming 33 MPH)

If I went 5,000 miles at 12.7 MPG I would have burned 393.7 gallons of fuel, that would be 362.32 hours at 13.8 MPH.

If I changed my oil at 256.41 gallons burned at 12.7 mpg/13.8 MPH, that would give me a run-time of 235.97 hours/3,256.41 miles.

I think on the Ford Superduty trucks they used recommend 3 months/5,000 miles, 200 engine hours or 250 gallons of fuel burned, whichever occurred first. This was for the diesel trucks with oil-fired injectors that were prone to shearing the oil down quickly.

https://www.fleet.ford.com/truckbbas/non-html/DeiselTips/DLSIDLETIMESS.pdf
 
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Judging by the condensation on your oil fill cap, I would be more worried about contamination build up than mile equivalents, or oil break down.
 
Originally Posted By: Oldtom
How about installing a Fram Ultra and a Fumoto drain valve? Leave the Ultra on for a full year, but change the dino oil three times a year. The Fumoto will make oil changes quick and easy. Use any dino with a reputation for cleaning.

Do change the PCV valve. The PCV on my Dodge Caravan still rattled when shaken, but, a new Mopar PCV cut oil consumption down to nothing. Also, the oil seems cleaner at the same mileage.

I've thought about using a filter for multiple OCI's, our diesels run the same oil/filter for up to 500 hours. I don't see why a gasoline engine couldn't use the same filter for 3-400 hours. I can't say for sure that the Ultra would add much protection over the Toyota filter. I really don't think filter efficiency means much until you start talking about bypass filtration. Oil analysis companies will tell you that they can't tell any difference between UOAs with different brands of decent/reputable spin-on filters. Oil analysis companies will also tell you that they don't see any difference in wear between Dino and synthetic oil, Dino just breaks down and need to be replaced sooner than synthetic. I think my issue is accumulated moisture, which neither Dino or synthetic oil can deal with in large quantities, so I'm almost of the opinion that I should use a cheap oil and change it more often.
I will not use a Fumoto valve on this truck because it is operated in off-road conditions and I am concerned that it could get snapped off if I were to hang it on something or bottom out over something. This truck is ridiculously easy to change the oil on.

Im for sure gonna change out the PCV valve when I get time to go pick one up.
 
Get yourself an infrared temperature gun. They're like $30-$40 bucks online. Can be used for lots of cool things like finding a sticky brake caliper (one rotor hotter than the other). Do one of your short trips and shoot the temp gun at the oil pan or oil filter. Even if your coolant is at 220F I bet your oil isn't anywhere near that. After a ten minute drive it's likely not even 180F. Water boils at what? So if you short trip a lot, you're not burning the condensation out affectively. Of course localized oil temp throughout the engine will differ, bearing temperatures can be 300F while pan or sump temps are low 200's, but the whole capacity of oil needs to be able to burn off condensation from time to time to avoid creating acidity. Take her out on a long drive regularly. As antidotal as this is, whenever I drive my Marauder it goes at least 25 miles highway, most of the time more than that. It's an '03 with 113k on it, and lives on Valvoline Synthetic. The valvetrain and heads look like a new crate engine. Zero varnish. Still bright shiny aluminum and steel. Take this for what it's worth.
 
Originally Posted By: BlueOvalFitter
Originally Posted By: Bjornviken
Tray a amsoil 5w-30 singature series

What will this oil do for his engine that some other 5W30 synthetic can/can't do?

I can’t say for sure what difference it would make but Amsoil Signature is indeed significantly than most big oil companys’ synthetics. It contains a decent percentage of ester base oil and it has a large concentration of detergents, mostly of the calcium variety. Those are two of the main differences that could benefit the original poster. There are likely more significant differences in the ashless additives used that don’t show up in UOAs.
 
Originally Posted By: BlueOvalFitter
Originally Posted By: Bjornviken
Tray a amsoil 5w-30 singature series

What will this oil do for his engine that some other 5W30 synthetic can/can't do?



Noack volatility?
 
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