Using thicker engine oil to prevent burning?

Nash Bridges

I have a ’03 Avensis 1.8 Petrol, 125k miles (newer model). Yesterday the oil light flickered while driving. The oil level was below dipstick and it took 2 litres to get it up to dipstick level again. Hopefully I haven’t damaged the engine but will replace the oil and filter tomorrow in any case.

I know that this is a common problem with some Toyota petrol engines of this age. This is a reasonably recent problem, the last oil and filter change was in April and there were no leaks or burning during the previous 12 months. There are no oil stains under where I park the car every day so I’m pretty sure the problem is burning. Doing any serious engine repair or overhaul is out of my budget at the moment and a 9 year old car with 125,000 miles is definitely out of warranty so I plan to keep the car limping along by keeping a close eye on the oil level and topping up as needs be.

Having researched Honest John, Boards and Toyota owners club there are a lot of mixed messages out there. Some suggest fully synthetic 0w30, others to use more viscous oil e.g. 10w40 (recommended is 5w30). It would make sense to me that a thicker oil would transfer less into the cylinders but may be less fuel efficient and harder for the engine coming into winter.

Has anyone an opinion on using a thicker engine oil to prevent or reduce burning? Will it help or is it best to just use the recommended grade?

Nash Bridges

Nash Bridges wrote: »

..........the last oil and filter change was in April ...............recommended is 5w30............

I'd top up with the recommended oil, it might only be burning a small drop. At least top up with the 5w30 until you quantify how bad it is

Bigus

It might seem counter intuitive , but maybe add a can of flush before you do the oil change, it might free up the oil rings a bit.

I'd go with the heavier oil too, after all the clearances are all loosened up now , so thicker oil won't slosh around as much onto the hot cylinder walls.

maidhc

The problem with these engines isn't wear, but the oil control rings getting gummed up. Some people seem to have had positive experiences of using engine flush and the like.

Nash Bridges

Thanks for the responses, I'll definitely give the engine a flush before changing the oil, maybe an additive in the fuel next fill would be helpful too.

I think I'll stick with the recommended oil grade though. I'm worried that I might end up causing more serious problems with the engine with thicker oil.

Nissan doctor

Using a thicker oil will only mean that the rest of your engine isn't getting the correct lubrication.
It may mask the problem in the short term, but it will never fix the problem.

stimpson

Castrol do a high mileage oil. I tried it in the CRX and she barely used anything between oil changes. She used to drink 500ml between changes. It should be the same grade as speced so no worries about performance.

Nash Bridges

That high mileage oil sounds ideal but I already changed oil and filter on Saturday. I used the recommended grade just in case I caused any bigger problems. I also gave the old oil a flush as some suggested and the engine is running an awful lot smoother now.

Will just keep a close eye on oil level from now on, and hopefully it will be a bit better. Thanks to all again!

ferrismrk

Is the car still using oil, or did the flush work. I only ask 'cause my Avensis is doing exactly the same thing.

corkgsxr

10w40 would be fine in them

Nash Bridges

ferrismrk wrote: »

Is the car still using oil, or did the flush work. I only ask 'cause my Avensis is doing exactly the same thing.

Yes the flush worked. Or at least there is a massive improvement.

I checked just now and the oil level has dropped slightly, maybe 40% of the distance between the min and max marks on the dipstick, if that makes sense. That's with 3 months and about 2500 miles of driving. That's okay I think for a 10yo car, certainly better than ~2litres burned in the previous 6 months.

So based on mine, use the flush, exact recommended oil and change filter too. Should at least provide a decent improvement. Good luck!

2pack

im sure this would also help if a diesel car was very smokey due to engine wear