Substitute 5W30 for 10W40 in my 1988 Toyota Celica

[Lightsilver]

I have a 1988 Toyota Celica that I bought brand new.

I'm getting older, and only put about 1000 miles a year on it these days.

The owner's manual calls for 10W-40 above 32F, and 5W-30 below 32F. Since I only drive it in the summer, I've been using 10W-40 castrol dino oil.

I'm wondering if it would be OK to use 5W-30 Castrol dino oil during the summer.

The reason I ask is my primary vehicle uses 5W-30 year round, and I have quite a lot on hand; several cases of 24 quarts.

I know oil has improved quite a bit over the last 20 years.

The Celica has a VERY small oil leak I haven't been able to trace. I find oil stains in the newspaper under the car about the size of a quarter: a few drops, at most.

I've never seen any loss on the dipstick...in the 1000 miles I drive it each summer.

It would just make it a little easier for me f I could use the 5W-30 oil I have on hand, so I don't have to buy 4 quarts of 10W-40 every fall, to change the oil in the Celica.

Thanks guys!

 

[HTSS_TR]

The oil spec'ed of my E430 is Mobil-1 0W40 and it has xW20 since 2007-2008 without any problem, actually the engine is much quieter with thinner oil and fuel mileage improves by about 4-5%.

If you use 5W30 in your Celica, you may need to check oil level a little more often. Go ahead use 5W30 in summer as long as you race your car.

For the oil leak on the ground, it may be as easy as tighten the oil pan screws.

 

[fdcg27]

First off, I offer you my highest regards for having had a car for that long from new.
Now, wrt oil, the 10W-40 of the mid to late 'eighties was probably not much thicker than the 5W-30 of today after a few thousand miles of use.
I am also assuming that you aren't beating on the car.
I would therefore say that a current 5W-30 would probably be okay.
I might use it myself in an old Japanese car, like the mid 'eighties Civics we had back in the day.

 

[tinmanSC]

Originally Posted By: HTSS_TR
Go ahead use 5W30 in summer as long as you race your car.

One assumes this is supposed to be "as long as you don't race your car."

And I can't imagine that 5w-30 would hurt anything in that car.

 

[Lightsilver]

Originally Posted By: tinmanSC
Originally Posted By: HTSS_TR
Go ahead use 5W30 in summer as long as you race your car.

One assumes this is supposed to be "as long as you don't race your car."

And I can't imagine that 5w-30 would hurt anything in that car.


LOL. That's what I assumed.

When the car was newer, (and I was 20 years younger...) I often drove it fairly hard, but now, I don't even come close to the red line, and I drive the speed limit.

It's still fun to drive, once in awhile....but I'm afraid I've gotten used to my primary vehicle, which has power locks and keyless entry, a (GASP!) auto transmission, ABS brakes, air bags, and I sit about 2 1/2 feet higher (at LEAST) off the pavement.

I'm really getting OLD.

 

[Trav]

I take care of a few older Toyota's one is 86 Corolla GTI 16v
It has the same spec 10w-40 summer 5w-30 winter spec as yours.
I found using 5w-30 in summer it used a little oil, if that's not an issue then there is no problem running it.

 

[Lightsilver]

Originally Posted By: Trav
I take care of a few older Toyota's one is 86 Corolla GTI 16v
It has the same spec 10w-40 summer 5w-30 winter spec as yours.
I found using 5w-30 in summer it used a little oil, if that's not an issue then there is no problem running it.


I think that your car has the 1600CC 16 valve engine, the same as was used in the MR2,while mine has the 2000cc 16 valve engine...but I'm not positive.

A little oil use would be OK. I drive it so little, and I'm pretty anal about checking the oil level anyways.

I have so much 5W-30 oil on hand; I bought it in 2007 or 2008, BEFORE oil hit the ceiling in 2008.

I can't remember how much I paid; probably around $1 to $1.50/quart, on sale with rebates.

I remember it seemed 'cheap'.

 

[chad8]

I have a couple older corolla's. I have owned 10 Toyota's including the 3.0 sludge motors that never did..
They are easy on oil. 5w30 is ideal for year round use unless it burns oil. Then 10w40 is a little better to stop the burn. 5w30 is better for mileage but at 1000 miles a year , you could run about any oil on earth.
I have run everything from supertech to mobil 1.
Any decent dino oil like penzoil yellow , castroil , or even supertech is fine. The older ones like a little more robust(thicker) oil.

 

[HTSS_TR]

Originally Posted By: Lightsilver
Originally Posted By: tinmanSC
Originally Posted By: HTSS_TR
Go ahead use 5W30 in summer as long as you race your car.

One assumes this is supposed to be "as long as you don't race your car."

And I can't imagine that 5w-30 would hurt anything in that car.


LOL. That's what I assumed.

I'm sorry, I was in a hurry. Your assume is correct.

Your engine will rev easier with thinner oil and it is possible that it will be quieter.