German Castrol in V-6 Camry -- I'm Concerned.

[huffmuds9320]

Haven't used the Castrol 0w-30 yet, but I remember on the back of the bottle does not say Energy Conserving on the lower portion. Since the Amsoil 5W-30 is energy conserving, maybe thats why it gives you that extra 1mpg difference. Overall the Castrol is a great oil from what most people say, probably was really made for european cars.

 

[Brett Miller]

I put GC in my S-10 4.3 after running Mobil 1 for 46,000. I have not noticed any difference in gas mileage, but the engine is definately quieter.

 

[buster]

Quieter is a superficial quality that really isn't that important IMO> Basically any thicker oil will make the engine sound louder, and probably oils with tons of additives like RL. More dense oils keep the noise down.

Frictional benefits I would think, should show via MPG changes.

 

[ekpolk]

Correction to my last: the VVT-i 1MZ for Camrys makes 210 hp vs. 220. 220 is the output for the Highlander/RX version of the engine.

Buster: "Quietness" is a pretty subjective value, that varies in importance depending upon the person and situation. To me, a sudden, and unexpected increase in noise level is very important, at least until I pin down why it happened.

 

[haley10]

I would put in a new fuel filter and run some different fuel like Conoco or Citgo.

It may be somewhat coincidental and the oil switch just magnifies it.

I had a similar situation. Some car don't like Formula Shell gas if you've been running that.

I'd eliminate that issue first before I condemed the oil. Sounds like a fuel issue that needs to be resolved 1st.

 

[haley10]

Maybe you have answered your own question. It may be that the VVT needs a starburst oil to work correctly. May be that it's only going to like the thinner 30wt's.

 

[ekpolk]

quote:

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Originally posted by haley10:
Maybe you have answered your own question. It may be that the VVT needs a starburst oil to work correctly. May be that it's only going to like the thinner 30wt's.

---

As much as I tend to fall in love with my own ideas (who doesn't...), the VVT-i theory is just that, another theory. I put it out there to see if it sparked some recognition with other members. The previous oil, Amsoil 5w-30 ASL, which seemed to run very nicely, is neither API licensed nor starbursted. In fact, its on-paper stats are very similar to the GC (other than it being a 0w- vs. a 5w- oil. For now, I'm going to fiddle with things, one at a time, to see if something else (oil filter, etc.) might be off instead of the oil.

 

[Dr. T]

Whereas the Amsoil is probably a better quality lubricant (aka boutique oil), I agree with Terry...you guys need to give things some time.

 

[2x]

I have a 99 Civic and before I was running M1 5w-30 and Amsoil ASL 5w-30 and with the GC now in it for two runs the mileage is definitely lower with no other variables changing. Used to do 34-38 on the highway, now does 31-33 with GC. GC is good, I like it in my car because it is quieter than M1, but the difference in MPG is undeniable. Don't need a UOA to prove anything. Switch to a lighter 30 weight IMO. I bet all will return to normal.

2x

 

[2533a]

quote:

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Originally posted by buster:
Amsoil S2k used to thicken real bad, (seems to be much better now) and that is why I think RL found it to lose its CF over the course of the interval.

---

Buster,

What does "CF" stand for? Terry referred to it as well though as "Cf".

Thanks!

 

[quadrun1]

Coefficient of friction

 

[C4Dave]

An interesting experiment would be to put 5w20 in and see what it does to the mpg's.

 

[kev99sl]

Just a general comment after reading some replies to the original post, since this is one of my (admitedly many) pet peeves.

The way some folks approach troubleshooting a problem makes me chuckle.

Here's a hint: if a person changes his oil, and immediately notices a 4 MPG drop in mileage, sluggish performance, and a louder engine, guess what? The oil should actually be the first on the list of suspects, not the very last. Not fuel. Not air filters. Not headwinds and tailwinds.

I understand that there are all sorts of variables that go into ascertaining what may be causing a change in performance, but doesn't logic dictate to all reasonable human beings that the one and only variable that was verifiably changed should be the first avenue of investigation? Uh, yes. It is very likely that, given time, this oil will be just fine in this application. But it is also very likely that it is indeed the oil that is causing these changes.

All other factors, outside of the one and only factor actually, deliberately changed, come in whatever order you please after ruling out that one and only factor that was actually, deliberately changed.

 

[jason07-1zzfe]

Yeah it should if the change is consistent with a magnitude of change that can be affected by motor oil. Oils do not make a 4mpg change. Unless he mistook a bucket of asphalt for the bucket of motor oil!

 

[kev99sl]

quote:

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Originally posted by Jason Troxell:
Yeah it should if the change is consistent with a magnitude of change that can be affected by motor oil. Oils do not make a 4mpg change. Unless he mistook a bucket of asphalt for the bucket of motor oil!

---

First off, on what basis do you say that a change of oil cannot account for a 4 MPG change?

Second, logic still dictates that if that is the one known, changed variable, that's still the place to start, right?

 

[jason07-1zzfe]

Just a hunch

 

[Brian Barnhart]

I wonder if spark plugs, tires, air filter, fuel filter etc. would have been mentioned as possibilities if the oil used would have been something like Valvo State instead of GC? The issues appeared suddenly when the oil was changed. If the problem isn't the oil, it's something else that occurred at nearly the same time as, or perhaps during, the oil change. I'd be real surprised if one of the other "wear" items mentioned above caused an abrupt change like that described.

A spark plug wire, electrical or vacuum connection, etc. loosened during the oil change might be a possibility. I'd check those and if I found nothing, I'd dump the GC.

 

[ekpolk]

quote:

---

Originally posted by kev99sl:
Just a general comment after reading some replies to the original post, since this is one of my (admitedly many) pet peeves.

The way some folks approach troubleshooting a problem makes me chuckle.

Here's a hint: if a person changes his oil, and immediately notices a 4 MPG drop in mileage, sluggish performance, and a louder engine, guess what? The oil should actually be the first on the list of suspects, not the very last. Not fuel. Not air filters. Not headwinds and tailwinds.

I understand that there are all sorts of variables that go into ascertaining what may be causing a change in performance, but doesn't logic dictate to all reasonable human beings that the one and only variable that was verifiably changed should be the first avenue of investigation? Uh, yes. It is very likely that, given time, this oil will be just fine in this application. But it is also very likely that it is indeed the oil that is causing these changes.

All other factors, outside of the one and only factor actually, deliberately changed, come in whatever order you please after ruling out that one and only factor that was actually, deliberately changed.

---

This is why I had mentioned the filter as a possibility, since I actually chaged two variables, the oil and its filter. Filter changes on a V-6 Carmy are absurdly easy -- the only trick is not burning yourself on the front bank exhaust manifold. I can reach in and get it off by hand without even using a wrench. So I figured change it first in case it was some oddball filter problem.

 

[JeepZJ4.0]

quote:

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Originally posted by ekpolk:

quote:

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Originally posted by ChrisW:
are you still on the original tires at ~30k miles? Some tires reduce mpg as they wear, but i dont know if it's enough to cause a 4mpg difference.

Spark plugs maybe are worn somehow? though i think the newer toyotas use 100k miles platinum plugs.

I too would not point the finger at the oil just yet, though it does seem like it eh?

---

Yeah, the original Goodyear Integritys are still installed. They are about half gone, at least from looking at the treadwear situation. Not a very inspired tire, but by running it at about 36-38 psi, vs. the Toyota recommended 29, I get a blend of crispness, ride, and somewhat enhanced mileage that I like. BTW, the GY max for the tire is 44. Checked the tires after last night's run just to make sure, and they're all stable.

Hadn't considered the plugs, but given the abrupt onset of the unsmoothness and decreased mpg, coinciding with the OC, I'm still looking at the new oil.

---

The Goodyear Integritys aren't exactly the nicest tire. If possible, I'd switch those out for Yokohamas, Michelins or Bridgestones.

The plugs.... DOn't touch them for 100K. We have a 1MZ in our 02 Toyota Avalon. If you look under the hood, service spark plugs with Iridium tipped plugs or something to that effect. In other words, these plugs will out last platinums and they are fantastic. I doubt the oil would be a problem, especially in a 1MZ. In my 4.0L I6 Jeep engine, I'd believe it since the engine was designed in the 60s. Good luck! Keep the GC.... maybe it's cleaning out some stuff that the other oil left behind....

 

[jsharp]

quote:

---

Originally posted by kev99sl:
Just a general comment after reading some replies to the original post, since this is one of my (admitedly many) pet peeves.

The way some folks approach troubleshooting a problem makes me chuckle.

Here's a hint: if a person changes his oil, and immediately notices a 4 MPG drop in mileage, sluggish performance, and a louder engine, guess what? The oil should actually be the first on the list of suspects, not the very last. Not fuel. Not air filters. Not headwinds and tailwinds.

I understand that there are all sorts of variables that go into ascertaining what may be causing a change in performance, but doesn't logic dictate to all reasonable human beings that the one and only variable that was verifiably changed should be the first avenue of investigation? Uh, yes. It is very likely that, given time, this oil will be just fine in this application. But it is also very likely that it is indeed the oil that is causing these changes.

All other factors, outside of the one and only factor actually, deliberately changed, come in whatever order you please after ruling out that one and only factor that was actually, deliberately changed.

---

Actually, before I questioned "the last thing I changed," I'd question the accuracy of my measurement. This is especially true when whatever I changed is not likely to explain the results I'm seeing, and I've only made one measurement. After repeated measurements within a reasonable percentage of the first one I'd be inclined to look at the last thing I changed...