Viscosity Of Oil

[hallelujah]

RECENTLY HAD 1ST SERVICE, OIL USED WAS W5-30,INITIALLY I LOST AROUND 7 TO 8 MPG AND PERFORMANCE DROPPED OFF, BUT AFTER AROUND 200 MILES THE OIL SEEMS TO HAVE LOST SOME OF ITS VISCOSITY AND ECONOMY AND PERFORMANCE ARE BACK TO NORMAL

[Grumpy Cabbie]

It won't be for long - I can assure you!

Say goodbye to 60+ mpg. Say goodbye to smooth engine starts in town.And say goodbye to performance in power mode. The car requires 0w20 and the dealer should know this, so get them to sort it out pronto. You'll regret it if you don't.

[dwilson]

RECENTLY HAD 1ST SERVICE, OIL USED WAS W5-30,INITIALLY I LOST AROUND 7 TO 8 MPG AND PERFORMANCE DROPPED OFF, BUT AFTER AROUND 200 MILES THE OIL SEEMS TO HAVE LOST SOME OF ITS VISCOSITY AND ECONOMY AND PERFORMANCE ARE BACK TO NORMAL

How do you know the viscosity of the oil used - did the dealer tell you?

What reason did they give to using the wrong one?

Picking up my first 1.5 Prius next weekend, but not my first Toyota, and this just seems very strange to me.

[Grumpy Cabbie]

RECENTLY HAD 1ST SERVICE, OIL USED WAS W5-30,INITIALLY I LOST AROUND 7 TO 8 MPG AND PERFORMANCE DROPPED OFF, BUT AFTER AROUND 200 MILES THE OIL SEEMS TO HAVE LOST SOME OF ITS VISCOSITY AND ECONOMY AND PERFORMANCE ARE BACK TO NORMAL

How do you know the viscosity of the oil used - did the dealer tell you?

What reason did they give to using the wrong one?

Picking up my first 1.5 Prius next weekend, but not my first Toyota, and this just seems very strange to me.

You'll be ok with 5w30 with the 1.5 I believe. It's just the new 1.8 than must have the 0w20 oil as the engine is tighter for better economy etc.

Edited August 9, 2010 by Grumpy Cabbie

[hallelujah]

YES I ASKED DEALER WHAT OIL WAS USED AND THEY TOLD ME 5-30, INCIDENTALLY BOTH OWNERS HANDBOOKS FOR GEN 2 AND GEN 3 SAY 0-20, BUT ALSO SAY IF 5-30 IS USED IT SHOULD BE REPLACED WITH 0-20 AT NEXT SERVICE SO ITS NOT ABSOLUTELY CRITICAL , THE TOLERANCES ON THE 1800CC ENGINES WILL BE THE SAME AS IN VERSO OR AVENSIS ETC, ITS BASICALLY THE SAME ENGINE BUT RUNNING ON AN ATKINSONSON CYCLE WHICH IS TO DO WITH THE ECU MAPPING RATHER THAN TOLERANCES OF ENGINE BUILD

[dwilson]

RECENTLY HAD 1ST SERVICE, OIL USED WAS W5-30,INITIALLY I LOST AROUND 7 TO 8 MPG AND PERFORMANCE DROPPED OFF, BUT AFTER AROUND 200 MILES THE OIL SEEMS TO HAVE LOST SOME OF ITS VISCOSITY AND ECONOMY AND PERFORMANCE ARE BACK TO NORMAL

How do you know the viscosity of the oil used - did the dealer tell you?

What reason did they give to using the wrong one?

Picking up my first 1.5 Prius next weekend, but not my first Toyota, and this just seems very strange to me.

You'll be ok with 0w30 with the 1.5 I believe. It's just the new 1.8 than must have the 0w20 oil as the engine is tighter for better economy etc.

Interesting - thanks for this

[dwilson]

YES I ASKED DEALER WHAT OIL WAS USED AND THEY TOLD ME 5-30, INCIDENTALLY BOTH OWNERS HANDBOOKS FOR GEN 2 AND GEN 3 SAY 0-20, BUT ALSO SAY IF 5-30 IS USED IT SHOULD BE REPLACED WITH 0-20 AT NEXT SERVICE SO ITS NOT ABSOLUTELY CRITICAL , THE TOLERANCES ON THE 1800CC ENGINES WILL BE THE SAME AS IN VERSO OR AVENSIS ETC, ITS BASICALLY THE SAME ENGINE BUT RUNNING ON AN ATKINSONSON CYCLE WHICH IS TO DO WITH THE ECU MAPPING RATHER THAN TOLERANCES OF ENGINE BUILD

Thanks for this info. Reassuring that the dealer didn't use the wrong oil but a bit surprising they didn't use the optimum one. Cheers.

[johalareewi]

As explained in a recent thread somewhere (and on Toyota blog)

Gen2 = 5w30

Gen3 = 0w20

[Ancient Nerd]

YES I ASKED DEALER WHAT OIL WAS USED AND THEY TOLD ME 5-30, INCIDENTALLY BOTH OWNERS HANDBOOKS FOR GEN 2 AND GEN 3 SAY 0-20, BUT ALSO SAY IF 5-30 IS USED IT SHOULD BE REPLACED WITH 0-20 AT NEXT SERVICE SO ITS NOT ABSOLUTELY CRITICAL , THE TOLERANCES ON THE 1800CC ENGINES WILL BE THE SAME AS IN VERSO OR AVENSIS ETC, ITS BASICALLY THE SAME ENGINE BUT RUNNING ON AN ATKINSONSON CYCLE WHICH IS TO DO WITH THE ECU MAPPING RATHER THAN TOLERANCES OF ENGINE BUILD

Gen II uses 5W-30. The manual doesn't include 0W-30 let alone 0W-20. I'm surprised, because I would have thought the 0W-30 would be perfectly reasonable, it would just give improved performance/economy when cold. No difference when hot.

I haven't checked this with either Toyota or the dealer. Has anyone else?

Yes, I know I've got a Gen III, but the old Gen II is still in the family, and I've got enough 0W-30 available for the next two services.

[hallelujah]

As explained in a recent thread somewhere (and on Toyota blog)

Gen2 = 5w30

Gen3 = 0w20

PAGE 427 PRIUS 2 HANDBOOK PREFERRED OIL IS 0-20 BUT 5-30 MAY BE USED BUT SHOULD BE REPLACED WITH 0-20 AT NEXT SERVICE. PAGE 546 PRIUS 3 HANDBOOK IF 0-20 IS NOT AVAILABLE THEN 5-30 IS ACCEPTABLE ALTERNATIVE BUT REPLACE WITH 0-20 AT NEXT SERVICE

[Ancient Nerd]

As explained in a recent thread somewhere (and on Toyota blog)

Gen2 = 5w30

Gen3 = 0w20

PAGE 427 PRIUS 2 HANDBOOK PREFERRED OIL IS 0-20 BUT 5-30 MAY BE USED BUT SHOULD BE REPLACED WITH 0-20 AT NEXT SERVICE. PAGE 546 PRIUS 3 HANDBOOK IF 0-20 IS NOT AVAILABLE THEN 5-30 IS ACCEPTABLE ALTERNATIVE BUT REPLACE WITH 0-20 AT NEXT SERVICE

Thanks. What date was the Gen II Prius? It looks as though this changed in the later days of the gen II. Mine was April 2008 and included no 0W options at all. I'll check with dealer before the service, as the car is now on extended warranty (70,000 coming up)

[Grumpy Cabbie]

In a previous post I put 0w30 instead of 5w30. Apologies for adding confusion to an already confusing issue.

As others have said;

Gen 2 = 5w30

Gen 3 = 0w20

Use of other grades is upto you.

[timberwolf]

In a previous post I put 0w30 instead of 5w30. Apologies for adding confusion to an already confusing issue.

As others have said;

Gen 2 = 5w30

Gen 3 = 0w20

Use of other grades is upto you.

On the first service last year of my Gen 2, the dealer (Kings) refilled with Castrol SLX 0W/30. But they over-filled the oil and it was a fight to get them to put it right

[johalareewi]

PAGE 427 PRIUS 2 HANDBOOK PREFERRED OIL IS 0-20 BUT 5-30 MAY BE USED BUT SHOULD BE REPLACED WITH 0-20 AT NEXT SERVICE. PAGE 546 PRIUS 3 HANDBOOK IF 0-20 IS NOT AVAILABLE THEN 5-30 IS ACCEPTABLE ALTERNATIVE BUT REPLACE WITH 0-20 AT NEXT SERVICE

Official Toyota info:

Melissa Coulton says:

March 23, 2010 at 12:10

Hello again Kev,

Many thanks for your patience.

Toyota GB has now issued revised guidelines to all Toyota Centres, clarifying which oil grades are suitable for Toyota vehicles. I’m pleased to say that I am now in a position therefore to confirm the correct oil grade for use in third-generation Prius.

Third-generation Prius is filled with 0W-20 Toyota Genuine Motor Oil at the factory. This is also the recommended service grade to be used by Toyota Centres. (Please note that this is specific to third-generation Prius and Auris HSD only, and does not apply to previous generations of Prius or Toyota Optimal Drive vehicles.)

Second-generation Prius is filled with 5W-30 FE Toyota Genuine Motor Oil at the factory, with the same oil grade recommended at services.

We are not able to comment on the suitability of any non-Toyota oils.

I hope this has cleared up any confusion or uncertainty. Thank you once again for your patience.

http://blog.toyota.co.uk/new-prius-everything-you-need-to-know/comment-page-2#comment-10634

[kevin h]

PAGE 427 PRIUS 2 HANDBOOK PREFERRED OIL IS 0-20 BUT 5-30 MAY BE USED BUT SHOULD BE REPLACED WITH 0-20 AT NEXT SERVICE. PAGE 546 PRIUS 3 HANDBOOK IF 0-20 IS NOT AVAILABLE THEN 5-30 IS ACCEPTABLE ALTERNATIVE BUT REPLACE WITH 0-20 AT NEXT SERVICE

Official Toyota info:

Melissa Coulton says:

March 23, 2010 at 12:10

Hello again Kev,

Many thanks for your patience.

Toyota GB has now issued revised guidelines to all Toyota Centres, clarifying which oil grades are suitable for Toyota vehicles. I’m pleased to say that I am now in a position therefore to confirm the correct oil grade for use in third-generation Prius.

Third-generation Prius is filled with 0W-20 Toyota Genuine Motor Oil at the factory. This is also the recommended service grade to be used by Toyota Centres. (Please note that this is specific to third-generation Prius and Auris HSD only, and does not apply to previous generations of Prius or Toyota Optimal Drive vehicles.)

Second-generation Prius is filled with 5W-30 FE Toyota Genuine Motor Oil at the factory, with the same oil grade recommended at services.

We are not able to comment on the suitability of any non-Toyota oils.

I hope this has cleared up any confusion or uncertainty. Thank you once again for your patience.

http://blog.toyota.co.uk/new-prius-everything-you-need-to-know/comment-page-2#comment-10634

Hi,

thats the reply to me.

Whwn I insisted, very stronly, that they must use 0w20, the service manager walked past, went to the service bay, and returned with a can of 0w20 specially supplied by Toyota.

He assured me, and I did check later, that this oil would be used.

happy bunny, so far on the new tank of fuel I'm getting 75mpg as per the computer.

[Black Knight]

THE TOLERANCES ON THE 1800CC ENGINES WILL BE THE SAME AS IN VERSO OR AVENSIS ETC, ITS BASICALLY THE SAME ENGINE BUT RUNNING ON AN ATKINSONSON CYCLE WHICH IS TO DO WITH THE ECU MAPPING RATHER THAN TOLERANCES OF ENGINE BUILD

Some significant differences in the engine needed to run the Prius MODIFIED Atkinson cycle.

Cams and top end of the engine particularly

[Grumpy Cabbie]

THE TOLERANCES ON THE 1800CC ENGINES WILL BE THE SAME AS IN VERSO OR AVENSIS ETC, ITS BASICALLY THE SAME ENGINE BUT RUNNING ON AN ATKINSONSON CYCLE WHICH IS TO DO WITH THE ECU MAPPING RATHER THAN TOLERANCES OF ENGINE BUILD

Some significant differences in the engine needed to run the Prius MODIFIED Atkinson cycle.

Cams and top end of the engine particularly

Thanks for that Mr Knight. I just hope Hallelujah doesn't work in a service department at Toyota! I'm sure his assumption that all 1800cc Toyota engines are the same and oil is oil is probably rife within certain Toyota dealers too.

Perhaps a Toyota mechanic could confirm so we get clarification from the horses mouth so to speak

I personally will continue to insist on 0w20 as anything else makes the car run like sh**e (to use a Yorkshire-ism).

[acetip]

As explained in a recent thread somewhere (and on Toyota blog)

Gen2 = 5w30

Gen3 = 0w20

PAGE 427 PRIUS 2 HANDBOOK PREFERRED OIL IS 0-20 BUT 5-30 MAY BE USED BUT SHOULD BE REPLACED WITH 0-20 AT NEXT SERVICE. PAGE 546 PRIUS 3 HANDBOOK IF 0-20 IS NOT AVAILABLE THEN 5-30 IS ACCEPTABLE ALTERNATIVE BUT REPLACE WITH 0-20 AT NEXT SERVICE

hi prius owner

please excuse a auris owner trespassing on your forum, i admire the prius, indeed very very nearly got one, but present financial position dictated i put that on hold.

i like to put my pennies woth into this oil dicussion.

toyota advise using say for example 0-20 but you may use 5-30 (the suggest a simular thing wiyh the auris

they are not saying fill your engine with 5-30 at an oil change and then at your next service fill with o-20.

there would be no point.what i think they mean is you can use 5-30 for top up (should you need it. but at next oil

use the correct and prefered 0-20.

other wise why drive up to 10000 miles (between services with an inferor oil. and if you did this would it effect

a warranty claim.

i may be wrong but i dont think they have made this very clear.

[Grumpy Cabbie]

You're being very clear and it's a good point. You might have read some of my previous posts about the poor running experience I had when the wrong oil was used at service. It does make a heck of a difference.

[acetip]

You're being very clear and it's a good point. You might have read some of my previous posts about the poor running experience I had when the wrong oil was used at service. It does make a heck of a difference.

hi grumpy cabbie

i have indeed seen you and others complaing about increaed consumption when your engine has been filled with 5w- 30

instead of the 0-20.

i can understand when starting and during the warming up period the is increased drag,but i am surprised that when your engine is up to running temp that there is any noticable difference. but i dont have a prius so not in a position to judge.

an owner who do their own servicing would (in this country at least) make sure he has got hold of the correct oil

in time for when his service is due, and a toyota dealer should have the correct grade in stock.

prius owners are not the only toyota owners who have had the wrong grade to what is recommended by toyota to use

put in their engines by toyota dealers workshop.

toyota dealer seem to be able to with approval use any make of oil they choose,my local mr t uses Castrol,i dont know if its magnetec,or edge,others use Shell etc.

ford workshops have to use fords oil which is Mobil.

with a non freachised garage you are not sure what they use, and you can be sure it will be one type suits all.

my last 2 cars were mondeos and both still under warrnty i happy to have them serviced at my local ford (they were very good) but the passat td (1986) i had before them i had 15 years and did all oil changes myself.as with the jetta before that (6 years). i am very fussy about what oil goes into my engines.

sorry about the ramble but oil is the life blood of an engine.neglect anything but your engine oil.

[timberwolf]

i can understand when starting and during the warming up period the is increased drag,but i am surprised that when your engine is up to running temp that there is any noticable difference. but i dont have a prius so not in a position to judge.

I can remember after my first service, on grey November day, I got stuck on a cold, wind swept motorway before the engine had managed to warm up, and the engine temperature barely reached 43C the whole time I was stuck in the traffic jam with the engine periodically running for a short time to recharge the Battery. The normal operating temperature on a Gen 2 is about 87C.

[acetip]

i can understand when starting and during the warming up period the is increased drag,but i am surprised that when your engine is up to running temp that there is any noticable difference. but i dont have a prius so not in a position to judge.

I can remember after my first service, on grey November day, I got stuck on a cold, wind swept motorway before the engine had managed to warm up, and the engine temperature barely reached 43C the whole time I was stuck in the traffic jam with the engine periodically running for a short time to recharge the Battery. The normal operating temperature on a Gen 2 is about 87C.

hi timberwolf

it seems that toyota version of the atkinson engine is slower than their other petrol engines to reach normal operating temp.

i had diesel since 1986 and they all took at least 5 miles to be fully warmed.

so you can imagine i was surprised whe i got the auris i.6 vvti, how quickly it reached normal temp,at the very most 1 mile.,which benificial for an engine anyway.

[Grumpy Cabbie]

i can understand when starting and during the warming up period the is increased drag,but i am surprised that when your engine is up to running temp that there is any noticable difference. but i dont have a prius so not in a position to judge.

I can remember after my first service, on grey November day, I got stuck on a cold, wind swept motorway before the engine had managed to warm up, and the engine temperature barely reached 43C the whole time I was stuck in the traffic jam with the engine periodically running for a short time to recharge the Battery. The normal operating temperature on a Gen 2 is about 87C.

hi timberwolf

it seems that toyota version of the atkinson engine is slower than their other petrol engines to reach normal operating temp.

i had diesel since 1986 and they all took at least 5 miles to be fully warmed.

so you can imagine i was surprised whe i got the auris i.6 vvti, how quickly it reached normal temp,at the very most 1 mile.,which benificial for an engine anyway.

And that's one of the problems I guess. The thicker oil matched to an engine that doesn't get warm and also an engine that isn't on half as often as a normal car, esp in town driving like I do.

But it's not the full story. I remember going on a run to the coast and struggled to get 59 mpg when running with the wrong oil. With the correct oil it is easy to get mid to upper 60's mpg on the same run. Its hard explaining this to the dealers - complaining that I'm only getting 59 mpg instead of later 60's but hey, I bought the car for the fuel economy.

[Pkram]

RECENTLY HAD 1ST SERVICE, OIL USED WAS W5-30,INITIALLY I LOST AROUND 7 TO 8 MPG AND PERFORMANCE DROPPED OFF, BUT AFTER AROUND 200 MILES THE OIL SEEMS TO HAVE LOST SOME OF ITS VISCOSITY AND ECONOMY AND PERFORMANCE ARE BACK TO NORMAL

How do you know the viscosity of the oil used - did the dealer tell you?

What reason did they give to using the wrong one?

Picking up my first 1.5 Prius next weekend, but not my first Toyota, and this just seems very strange to me.

You'll be ok with 0w30 with the 1.5 I believe. It's just the new 1.8 than must have the 0w20 oil as the engine is tighter for better economy etc.

Interesting - thanks for this

Booked my Prius in for its first service and after being quoted the price asked which viscosity of oil would be used. When told this would be 5w-30 I declined and asked for the handbook recommended 0w-20. Said they would get it in. On collection after the service was told 0w-20 had been used. In fact from a 5 litre container which was not all used and the remainder of the container had been left in the car on a clean plastic bag. Full marks to Toyota at Derby.

pkram.

[Grumpy Cabbie]

Had my 30k service done last week and I stressed to them that I wanted 0w20 and they were very well aware of this, almost to the point that I think they must have had a bulletin from Toyota.

Anyway, service done and car runs well, very well infact. Also had the cabin airfilter changed (which should have been done at 20k) and the a/c now has more umpth and smells nice and clean.