sciontc_mich

Okay, friend got a 2006 RAV4 with the 4cyl engine. Since they're both 2AZ-FE,
why is it that the 06 RAV4 requires 5w-20 oil and 4.5 quarts? When the tC requires 5w-30 and 4 quarts?

Did the 06 tC change in its specs for oil and quantity?? Let me know.. Thanks.

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DouBLeJ16

That's a damn good question..

trialsindude

Possibly because the RAV4 has a bigger oil pan.....

Batjew

no. same engine in the 06 as 05, im sure there's a bigger filter in teh rav4, and considering it's an SUV, it'll work harder to pull more. again it's a manufacturer RECOMMENDATION, not set in the stone. and who's to say the engines are the same, the Carmy and tC engine aren't the same internally anyway.

SquallLHeart

hmm... though.. i have to add that many of the tC parts have seemed to work on the RAV4, which i did not know about.. met a guy that had one that said so. (can't remember what things though... i'm sure the CF engine cover was one of them.. haha.. duh..)

sciontc_mich

well the oil filter is the same exact filter for both engines, checked the part numbers.. the 90915-10004 fits both and is the same filter..

so my big question is.. why more quantity of oil? and why the change from 5w-30 to 5w-20 oil??

thanks for all the replies so far..

TheQuietThings

the only differences in the 2 engines i can find, is the compression, and the fuel delivery system.

The Rav4 has a 9.8:1 compression
tC has a 9.6:1 compression

RAV4 fuel delivery system is SEFI
tC fuel delivery system is MPFI

I'm really not sure if that has anything to do with why the oil weight is different, but its a possibility.

engifineer

check the oil pan.. same engine in no way means the same oil pan. It could be a different size due to clearance or other issues.

I dont know why the viscosity is different.. but I do know that they changed the internals on the 2az a bit.

And I dont know if you check your oil again after starting and idling the vehicle after an oil change (you should), but mine takes almost another 1/2 qt afterwards, as most do. That makes almost 4.5 qts

nodsetse

New Camry engine is 9.8:1 too, yet again has the same designation. Appears tCs have a unique engine, not likely to be used elsewhere.

Whocares05050

Intresting...

iowagary

What difference would the slightly lower compression make? Can anyone make a generalization there?

unsungfate

i thought that a higher compression ratio was better than a lower one?

DouBLeJ16

Higher compression is good for NA engines.. Lower compression is good for FI.

DouBLeJ16

I saw on tv yesterday that they're putting a 269hp V6 into the RAV4 now.. I don't suppose there is any hope for a swap into the tC?

engifineer

You can generate more power on the same platform with higher compression typically. Too high and you run a higher chance of pre-ignition, especially if you go FI, which is why you see people dropping the compression on an engine sometimes before adding FI. It depends on the starting ratio and how much boost you wish to run.

One drawback of running higher compression ratios like 11:1 is the need to run premium fuel to help prevent pre-ignition. Not really a huge price difference if you add it up over a year, but still something to consider. Some think it is costing them a fortune to run 91 instead of 89... which is not true if you actually do the math

If you want to run NA and produce more power, one option is to bump the compression up as long as you are within the limits of the system .

TheQuietThings

Higher compression means more air is being crammed into the engine, which normally results is more power, and worse fuel economy.

engifineer

^^ no, higher compression means just that.. .more compression. The higher you compress the gas the more power you can produce per ignition up to a limit. A higher compression piston on a stock bore and stroke has a domed top on it.

You can actually create power more efficiently with higher cr than with lower cr.

unsungfate

^^^^sweet, i want those 11.1:1 cams zpi has now...

sciontc_mich

interesting info from everyone.. glad i asked about the engine differences.. i was also curious.. does a higher CR mean better fuel economy? or just more power?

GT4Dreams

The 269 hp engine in the rav is a v6, not a 4 cylinder.

Higher Compressions = (in blunt explanation) more air and fuel in the same amount of space = more power.

Higher compression will require higher octane gas. Celica GTS compression is 11:8:1 I beleive, and it uses premium gas.

Higher compression cars don't equate to better fuel economy, but it does equate to more power (even if it's just a little bit more)

Turbo cars have lower compression because they have a turbo.