Is changing oil filter every other oil change OK?

Dealership overfill, in particular rounding up to the next quart (or litre) is something I've experienced too. It motivated me to go back to DIY. FWIW, our nearby Toyota dealership uses bulk oil, and measures specd quantity out carefully in large graduates. That's progress.

I'm sceptical that "Once the 5k mark had been reached, the oil had burned itself down to exactly the low level mark without going under." More likely you've just got some oil consumption, and should keep a close eye on it (which I think you're doing), and periodically top it up.

I don't see the statements in the Owner's Manual regarding "acceptable" oil consumption as indication this is normal. That rate of oil consumption is actually close to horrendous, lol. Such statements are likely put in there on advice of their lawyers, as a disclaimer.

My take: Toyota should be obligated to also put these oil consumption statements prominently in their glossy sales brochures.

FWIW, our 2010 so far (at 63,000 km) seems to consume no oil between changes. I am changing it much more frequently than than the US schedule though.

 

An "Interference Engine" is one where the valves will hit the pistons if the timing belt/chain breaks (A broken belt = New Engine!) . Our Prii have a timing chain which will give fair warning (noise) long before it breaks.

This has nothing to do with oil consumption. If any of your other cars has a timing belt, find out if it has an "Interference Engine". If so, it is absolutely necessary to replace the timing belt as suggested by the manufacturer. If it has a "Non-interference Engine" you can be somewhat lax with the timing belt maintenance as all that will happen if the belt breaks is that you will need a tow.

JeffD

 

You're misinterpreting what's written in the manual. What's indicated as acceptable/normal in the manual, would be the worst case scenario -- in the event that they have a bad one (no manufacturing process is 100% perfect), and a customer comes back demanding that the problem be corrected. Toyota could then say, "That's considered acceptable/normal... as indicated in your owner's manual."

It would typical for <100k Prius engine to consume less than one quart of oil (or as low as none) between 5K mile oil changes.
FYI: My 150K mile '08 burns 1/2 - 3/4 of a quart between 10K miles changes.

 

I know what interference is but have never heard it expressed as low interference in his low engine wear reference..
I happen to own an interference car with a belt. Fun.

 

The reason why the OM gives a notional value for acceptable (or normal) oil consumption has more to do with lawyers than engineers.
All engines will burn SOME oil, it's just that most ICEs burn a very trivial amount that's not easily measured by a metal stick with two reference marks stamped on it.
So.....if you have a company that doesn't want to replace motors that are burning oil at an unacceptable rate, you have to establish an "acceptable" rate....right?
That's why the value listed in the OM is as high as it is.

As far as the original 3-year-old question?

Easy.

If I'm replacing the oil?
I replace the filter.
HOWEVER....(comma!)
If the OCI is 10,000 miles and a customer wants to replace the oil (except what's in the filter) every 5,000 and the filter every 10,000 miles???
I'm cool with that for 2 reasons:
1. It's THEIR car.
B. The filter is being replaced within the maintenance periodicity.

For a DIY'er you get most of the benefit of a more practical OCI without having to deal with the filter every 5K.

 

The BEST New 2000 Toyota Prius 4cyl. 1.5L Oil Filter from Brandsport Auto Parts (#TOY-90915-YZZF2-Toyota-Prius-2000-4cyl-1-5l) Under $6 For New

2009 TOYOTA PRIUS Engine Over $600 for used.

If you drive less than a million miles per engine, it is cheaper to by filters.

 

A used oil filter is one of the most difficult to recycle items going, virtually a lost cause. If it it's completely unnecessary to change so frequently, it is very simple to cut their numbers in half.

 

I will find the information on the every other oil change filters . In the mean time I happened to find an article on how used oil is actually better than new oil. The Effect of Oil Drain Interval on Valvetrain Friction and Wear


update:
I haven't found any hard data on the every other oil change filters but have noted Honda has gone to recommending this practice. I would like to ask those that say we need to change the filter every time to come up with data on bad filters after 5k miles ? or even 10k?

 

Sure I'll clarify. The oil was in the midrange prior to a road trip, at the end of the trip it went to the low level mark but not under. I added a quart and it was full again.

By low interference I simply meant its not a high interference engine. The tolerances are slightly greater and theres not as much close friction and heat generation.

The point I was trying to make is that I don't believe that a fully broken in prius engine will clog a filter with particles within 5000 miles. If the automakers are able to suggest stretching oil changes to 10k miles or more, surely a filter can last 10k, especially on a very small displacement engine.

I had my oil changed at the dealer last month and have driven 5k miles since then. I doubt the filter needs replacement already. However the oil has become dirty so I may be comfortable changing the oil only.

 

Well, I consider a quart between oil changes to be moderate, considering it has 165k miles. The owners manual states that quite a bit more is normal, I agree that it shouldn't be acceptable. I'll have to read it again but I thought it said something like up to a liter per 900 km or something crazy like that.

I'm sure the 3rd gen was improved. The 2nd gen still seems advanced beyond its time in many ways, yet still archaic in others. Toyota had to cut some corners to make this vehicles a success, and an easy way to do so was probably an ICE that would have been great 30 years ago, with a ton of bolted on technology and upgrades.

 

The engine tolerances are greater than what? Thats pretty silly man. I assure you this engine has the same tolerances as any other engine with main difference being it has solid lifters. Which usually means more friction in the top end than an engine that uses hydraulic lifters.
It has a VVT section that requires very filtered oil in fact the VVT section of this engine has its own little filter.
So yeah it has pretty low tolerances. Very low tolerance of dirty oil.

Its not good to run the engine especially on a road trip with it being one quart low. The bottom end of this engine like most is splash lubricated. No splash no lubrication. Based on the amount of posts we have seen here with engine damage caused by low oil I would avoid running it low. If its low and your taking hard corners you could be losing scavenging.

And the terms engine interference and engine tolerances are 2 different worlds and have nothing to do with each other.

 

One quart below maximum capacity is still the bottom of the "safe" range. An engine with a 4 quart capacity will operate the same on 3 quarts as it will on 4, although the oil life will be diminished more rapidly. I've never actually had the oil level go officially "low", only to the bottom of the safe range before adding another quart.