Confused Soul Needs Advice On What Oil To Use (2001 Avensis, 1.8 Vvt-I

[Nimenomaan]

Uh oh, not another oil tread, you're probably thinking. Sorry about that, but I've been trying to read up on this, I'm just so overwhelmed with the amount of information spread over so many threads.

My car is a 2001 Toyota Avensis 1.8 VVT-I, ~107600 km driven. The oil was last changed in December when it was at 105000, the oil that was used was Castrol Magnatec 5W-40 C3 4L, I had bought the oil planning on doing it myself, but didn't have time so the mechanic did it while servicing the vehicle, I believe he poured in all of the 4 liters of oil (higher level than the max on the dipstick). As of right now the dipstick is at the max level, so it's using some oil (~1.2 dl/1000 km).

It seems like the car struggles a bit for the engine to fully start, I don't recall what it was like before the oil-change, unfortunately (5W-50 fully synthetic was used then).

It's about time for another oil change, and I'm so confused about what type and brand of oil to buy. Castrol and Mobil1 are probably the most readily available brands where I live (Norway). Should I get 0W-30, 5W-30, or another type?

When I check Castrol Norway's oil selector they recommend "EDGE (TI) 0W-30", but they don't mention if it's A5, B2 or C3 or something else. Any idea what "(TI)" means?

Mobil1 Norway's oil selector recommends "Mobil 1 ESP Formula 5W-30 (a)", what does "(a)" mean?

Certainly a longer thread than I had planned, but I would greatly appreciate if someone could help me out a bit! :)

[FROSTYBALLS]

On the UK sites for Castrol and Mobil don't have the suffixes you mentioned after the names of oil. Think Ti is some reference to titanium, but why I don't know.

The oil recommendations for Norway could well be different to the UK due to the difference in climate, operating temperature range, etc. The following topic gives the requirements for the UK - http://www.toyotaownersclub.com/forums/topic/148386-engine-oil/

5W-30 API SL. SM or SN would be the preference for a UK Avensis

[Ave I FIN]

I have used Teboil Diamond 5W40 for a couple of years. Oil consumption is about 3 dl / 1000 km (started at 90000, now driven 146000 km). With Mobil RF 5W50 it was about the same.

[Nimenomaan]

Thanks, I've decided to order Mobil1 ESP Formula 5W-30.

Should I add more oil than the max level on the dipstick, considering the engine type I'm blessed (/cursed) with? I think I've read that 1 cm above max is commonly used, or is that only if you make other modifications?

[FROSTYBALLS]

Never a good idea to overfill.

[Nimenomaan]

Hmm, quite a few people on this board with the same engine as I have seem to do it though. They all basically use the same amount as well.

"You are correct Devon Aygo, the sump was not changed. I have run my Avensis for a couple of year now with a modified dipstick,

+10 mm, green dot on the top. Presently I do not use a drop of oil"

"Anyway I did start using the high grade of unleaded and my oil consumption dropped to 1/3rd. However unfortunately at the same time I made a couple of other changes. I filled the oil 10mm above the full line to help the oil not get overheated ( factory mod with rebuilt engine has a higher dipstick line I understand) and I started using fully synthetic oil."

In the document attached to this post the 10 mm increase in oil levels is "part of the countermeasure".

[MarcosM12]

so some people have a modified dipstick? is this a factory re-design?

I know on most cars over filling on oil causes it to whip up and fill with air bubbles which leads to a loss of lubrication. Also can cause oil to to be forced up past the rings.

[Roker]

This is a factory mod, the 10mm + dipstick can be purchased from a Toyota dealers. part no 15301-0D011

The oil consumption issues affecting 1zz 1.8, 3zz 1.6 & 4zz 1.4 engines is caused by a combination of several issues, leading Toyota to make several changes to the engines up to around mid 2005 where they managed to cure the issues,

1. Insufficient oil capacity, pre 2005 engines only came with 3.7 litres of oil, this caused the oil to remain very hot all the time reducing the cooling affect the oil has on the back of the pistons. The continued high oil temps causes the oil to degrade and sludge excessively between service oil changes.
Toyota increased the oil capacity from 3.7 to 4.7 litres reducing the oil temps in the engine. ( EDIT On post 2005 cars Toyota increased oil capacity to 4.2 litres, On pre 2005 cars which had the official modifications carried out due to excessive oil consumption the oil capacity was raised to 4.7litres except for MR2's which stayed at 3.7litres due to the compact / shallow sump fitted to them )

2. Poor piston design, the rear of the piston only had 4 oil ways allowing the hot oil coming from the piston ring oil scrapers to pass away from the piston
rings. This meant that the oil stayed at the hottest part of the piston crown for too long exacerbating issue # 1 which in turn allowed the oil ways to sludge
up. Once sludging started the oil would eventually start to burn and harden around the rings this started to wear away at the bores eventually misshaping
them. Due to the Nikosil coating applied to the bores they should not be rebored or honed meaning Toyota replaced any block showing even the slightest
of damage. Toyota redesigned the pistons to include 8 oil ways which allowed the oil to pass away quicker.

3. The use of poor quality or overly thick oils (thicker than 5w30) increased the likely hood of the issues above occurring. Toyota noted that even dealers
where using oils such as 10w40 and quickly pointed out that although the owners manual listed 10w40 it was for warmer climates and that 5w30 was the preferred grade and insisted that dealers use 5w30 when servicing and repairing #zz engines.

4. Poor piston ring design, In an attempt to reduce friction, increase efficiency and lower emissions the engine designers profiled the piston rings to a sharp point reducing the contact point on the bore, this on its own only increased oil consumption slightly but when combined with issues 1,2 & 3 caused the piston rings not scrape the overly thick oils effectively. New piston rings where designed with a larger contact area and higher ring tension. Initially Toyota fitted new blocks along with modified pistons, rings, thermostat ( to lower engine running temp ) and a modified dipstick ( to show the new 4.7litre levels) they also recovered the old blocks eventually leading to them switching the approved repair method to remanufactured short blocks fully assembled with the modified parts. Oil consumption was an issue in both 1.6 3zz and 1.8 1zz / 2zz engines Toyota resolved this by raising the oil level 0.5 of a liter to improve piston cooling and adding more return holes in the piston skirt, but if any petrol engine is abused wrong oil / lack of service this will lead to carbon deposits / sludge which blocks the pcv system and causes oil to be forced pass the rings resulting in oil burning .good service history and correct oil is a must with these engines

[Raistlin]

http://www.toyotaownersclub.com/forums/tutorials/article/36-engine-oil-recommendations/

[Ave I FIN]

What oil to use if the engine is already burning oil? Keep using 5W40 and hope that the condition is does not get any worse or switch to 5W30 and add oil more regularly?

[MarcosM12]

I would probably start using 5W30 as its less viscous. This should be slightly beneficial to you according to 'Roker's' post. If your car is pre 2005?

[Ave I FIN]

Yes, it is 2001 1.8 1ZZ-FE .