I bought my '85 Peugeot 505 TurboDiesel with 272,000 on it (all the service
records since new!) Went to Mobil 1, 10w30 winter 15w50 summer. Uses about
1/2 quart 3,000 to 4,000 miles. Being a diesel and me being neurotic about my
cars, I change it between 3,500 and 4,000. I'll let the tow car go 3,500 and
the Peugeot V6 5,000. Also use Mobil 1 filter.
I also switched to 15w50 Mobil one in the last two tow cars, both big '70's
V8's, contrary to what everyone said, oil consumtion dropped to almost
nothing.....don't know why.....
Dan