Best oil for fuel economy?

[Dohc98vteC]

My Prelude has almost 142k and still going strong. I use Supertech oil filters and Valvoline All Climate 5w-30, at an 3k OCI. However, I add about a half quart between changes, due to the oil vtec will use up. I once switched to Castrol High mileage 5w-30 and didn't notice any mpg increase, what would be a good oil to use for best fuel economy at a reasonable price?

 

[dave1251]

You would be better off making sure that your tire's are inflated properly. Change your air filter at a reasonable rate. For better MPG motor oil does not help a lot.

 

[surfstar]

ditto.

You won't find any significant change from oil. Save money by buying any API SL/SM oil that's on sale (or rebate) and you'll be money ahead.

 

[TR3-2001SE]

I agree with the others. If you are using a 5w-30 there is little improvement by going to a 5w-20 or 0w-20. I have found you take a hit by going to 15w40 or 15w50 in milage but it is very small ie 1-2mpg.

 

[huffmuds9320]

Right, proper tire pressure is important to better gas mileage as well as regulsr maintenance. I don't think Honda recommends 5W-20 in that engine. Synthetic might give better fuel economy but not likely noticeable. Oil itself comaring the same weight like 5W-30 with regular, blend or synthetic would not result in any significant difference. I don't think you can get +5mpg by switching to synthetic.

 

[Rickey]

If you can stand the harsh ride and the handling is still Ok, pump the tires to the maximum inflation indicated on the sidewall. This "should" be worth 1 or 2 MPG. I did this on my '04 Cavalier and got an increase. Hard to say but at least 1 MPG. This was from an increase from 32 PSI to 38 PSI. The OEM tires are sidewall marked for 45 PSI max

. Yes I tried that pressure and it rode like a two horse wagon

Good luck... Rickey.

 

[deven]

Ummm...I am probably assuming that the original poster knows all the tricks for optimum gas mileage so your question about what oil to use....that is easy, the thinnest oil possible and that is 0w20. I have seen good uoa's with Mobil 1 0w20. Run it with confidence because contrary to popular old belief that its not lubricating properly is just nonsense. Just look at 0w20 uoa's. Like they say the proof is in the pudding. While minimal improvement in gas mileage but every little helps right?

 

[Rickey]

Yeah but he will be able to actually realize a difference from the inflation if he hasn't already tried it that is.

 

[Clyde65]

quote:

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Originally posted by Dohc98vteC:
I once switched to Castrol High mileage 5w-30 and didn't notice any mpg increase, what would be a good oil to use for best fuel economy at a reasonable price?

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When they say "High Mileage" they don't mean high fuel mileage.

 

[Dohc98vteC]

Haha, hey now I may be new on this forum, but I meant reducing oil consumption on that one

quote:

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Originally posted by Clyde65:

quote:

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Originally posted by Dohc98vteC:
I once switched to Castrol High mileage 5w-30 and didn't notice any mpg increase, what would be a good oil to use for best fuel economy at a reasonable price?

---

When they say "High Mileage" they don't mean high fuel mileage.

---

 

[TooSlick]

I'd clean the engine using Auto-RX and then go to a 0w-20 synthetic like Mobil 1. I'd also change the fluid in the five speed transaxle and install the Amsoil syncromesh fluid in place of the petroleum lube that's probably in there.

I think you'll see a gain of 3%-5% in fuel efficiency from doing these simple things.

TS

 

[Rand]

I dont think I would put a 20 wt oil in a prelude engine not spec'ed for it that has 140,000 miles on it.

 

[Ron AKA]

The critical oil paramater to look at is High Temperature High Shear viscosity (HTHS). The lower it is, the more fuel efficient the oil will be. This is because the losses are lowest in the engine, which in turn means the engine will also make more net HP. So look for an oil which has an HTHS of 2.6 or close to it. I believe 2.6 is lowest allowed HTHS. See this post for more information.

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=1;t=015836

 

[Clyde65]

Is 5W-30 an adequate barrier between moving parts on an engine with 140,000 miles on it? That's what you should ask yourself.

 

[greg_J35]

quote:

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Originally posted by Clyde65:
Is 5W-30 an adequate barrier between moving parts on an engine with 140,000 miles on it? That's what you should ask yourself.

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In my opinion,

Honda produces precision engines that are capable of going 300,000 + miles and if they reccomend 5w30 then it is good enough to go the distance.

 

[bobo]

I take it your objective is to save money. Perhaps you could start by extending your OCI beyond 3K, particularly given you add 1/2 quart between oil changes.

 

[MKR]

My "precision" Honda engine lasted 125,000 miles using 5w30, and then blew a rod through the side of the engine. Probably not the oil's fault though.

 

[brucelee]

"The critical oil paramater to look at is High Temperature High Shear viscosity (HTHS). The lower it is, the more fuel efficient the oil will be. This is because the losses are lowest in the engine, which in turn means the engine will also make more net HP. So look for an oil which has an HTHS of 2.6 or close to it. I believe 2.6 is lowest allowed HTHS. See this post for more information."

Well, not really. However, you might want to look at viscosity at 100C. This is likely a better parameter for guaging MPG per oil.

The HTHS simply tells how well the oil resists shearing, not how "heavy" it is.

 

[Ron AKA]

quote:

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Originally posted by brucelee:
"The critical oil paramater to look at is High Temperature High Shear viscosity (HTHS). The lower it is, the more fuel efficient the oil will be. This is because the losses are lowest in the engine, which in turn means the engine will also make more net HP. So look for an oil which has an HTHS of 2.6 or close to it. I believe 2.6 is lowest allowed HTHS. See this post for more information."

Well, not really. However, you might want to look at viscosity at 100C. This is likely a better parameter for guaging MPG per oil.

The HTHS simply tells how well the oil resists shearing, not how "heavy" it is.

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I believe the theory is that the oil temperature at the piston rings and journal bearings is well above 100 deg. C, and the HTHS is more reflective of the friction loss in the bearings and rings. Oil is being sheared in these locations. The higher the shear viscosity the higher the loss.

 

[Ron AKA]

quote:

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Originally posted by Dohc98vteC:
My Prelude has almost 142k and still going strong. I use Supertech oil filters and Valvoline All Climate 5w-30, at an 3k OCI. However, I add about a half quart between changes, due to the oil vtec will use up. I once switched to Castrol High mileage 5w-30 and didn't notice any mpg increase, what would be a good oil to use for best fuel economy at a reasonable price?

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As others have suggested the improvement will be relatively minor, but you should gain some by switching to a 5w20 with a HTHS of 2.6. Castrol GTX 5w20 is probably one of the economic choices. You may do a little better still with a 0w20, but that will cost you the price of a synthetic; Mobil 1 or Pennzoil Platinum. Also as others have suggested you can probably extend your OCI out to 5,000 miles or so, to save a few more $$'s.
Castrol GTX 5w20 Data Sheet