My Supra's Singing
 

Thank You MrKnickleye for all the excellent advice you have given me as to the upkeep of my Supra N/A. I am using the 20W 50 with a bottle of STP oil treatment. For fuel, I'm using 89 octane with that Dextron III fuel injector cleaner every 3 months and I gotta tell ya my engine has never run better. I have had an excellent summer, thank you. Now that winter is round the corner here in the New York City area, I'll be needin another oil change soon. You advised 10W 40 for winter and said it was good down to 20oF if I am not mistaken. But here in the Big Apple it can get well below 20. Should I consider a different weight? I don't drive in the snow but I do drive when it is very cold. Your advice has my car running in the best shape it ever has so I'll take your word as gospel. All you other folks out there have been very helpful too, but MrKnickleye had given me some very specific info, that's why I'm thankin him personally.

Scruffboy

Long cold winter needs 5w-30
 

According to our owners manual, pg 172 for the 1989, its recommended to use 5w-30 when constant temps will be below 50*F.

If your winter days are usually below that, like around 40*, (and lower) I would use 5w-30 oil.

It freezes here in winter, but the days get up into the 50's and 60's because of the sunshine.

I have seen many years when the temp can drop to the low teens at night, and only in the 30's in day. But that usually only lasts for a few days.

In the winter, I always let my car warm up in the driveway for about 5 minutes before driving. This lets the oil get warm and circulate everywhere before the stress of load is placed on it.

Thanks Pal
 

You have really helped me keep my car runnin top notch.

Scruff

this oil confuses me...

if your supposto (recomended) use 5w-30 in the winter, was it bad for me to use 5w-30 all summer?

i think next summer ill run 20w-50 full synthetic.

Our cars are old, and even when new, they were designed to run 10w-40 most of the time.

Many newer cars are running 5w-30 and synthetic 5w-30 because of the tighter clearances (bearings / pistons) due to increased (tighter / lower #s allowed) emission standards.

Perhaps 1 more MPG.

Also the tighter clearances require a thinner oil to help get it everywhere in the engine quicker.

plus if its hot and you have really thin oil then you could damage your engine, i've seen it happen to a friend of mine..