Originally Posted By: kschachn
I think the chart does allow 5W-20 for cold weather, but that was most certainly some inferior dino oil available in 1994. I think old charts are pretty much useless these days, irrespective of the fact that a lot of automakers seem to persist publishing them in today's manuals. I've seen some that really don't make sense.
I have some older vehicle charts and I've never seen one didn't make total sense to me.
The following I posted in another thread but it's applicable I think:
"Even for cars built in the 70's and 80's the 20W-20 grade was still spec'd as an option for fall, winter and spring use.
For my first car, a '72 Ford Capri, 20W-20 was spec'd for ambient temp's from 25F to 70F. My '86 Porsche has similar recommendation for the 20W-20 grade from -10C (14F) to 15C (60F).
Interestingly enough the 5W-20/30 grades were specified for my Capri only for sub-freezing temps from 32F down to -40.
Much the same for my Porsche with the 5W-20 grade from -10C (14F) and lower and a dino 5W-30 from -30C (22F) to 32F.
The 20W-20 grade had fallen out favour by that time because the now common 10W-30 grade had much better cold start performance, spec'd down to -25C (13F) although only up to 70F for both of these European cars.
Obviously manufacturers didn't have a lot of confidence in light multi-grade mineral oils of the day.
Porsche spec'd a 0W-30 up to 30C (86F)."
I think the chart does allow 5W-20 for cold weather, but that was most certainly some inferior dino oil available in 1994. I think old charts are pretty much useless these days, irrespective of the fact that a lot of automakers seem to persist publishing them in today's manuals. I've seen some that really don't make sense.
I have some older vehicle charts and I've never seen one didn't make total sense to me.
The following I posted in another thread but it's applicable I think:
"Even for cars built in the 70's and 80's the 20W-20 grade was still spec'd as an option for fall, winter and spring use.
For my first car, a '72 Ford Capri, 20W-20 was spec'd for ambient temp's from 25F to 70F. My '86 Porsche has similar recommendation for the 20W-20 grade from -10C (14F) to 15C (60F).
Interestingly enough the 5W-20/30 grades were specified for my Capri only for sub-freezing temps from 32F down to -40.
Much the same for my Porsche with the 5W-20 grade from -10C (14F) and lower and a dino 5W-30 from -30C (22F) to 32F.
The 20W-20 grade had fallen out favour by that time because the now common 10W-30 grade had much better cold start performance, spec'd down to -25C (13F) although only up to 70F for both of these European cars.
Obviously manufacturers didn't have a lot of confidence in light multi-grade mineral oils of the day.
Porsche spec'd a 0W-30 up to 30C (86F)."