Originally Posted By: Doug Hillary
The 20w-50 viscosity lubricant was especially developed during 1958-9 by Duckhams for use in the BMC (Austin - Morris) Mini. It was released about the same time as the car
This lubricant was needed because of the integrated engine-gearbox in these cars - they shared the oil with a common sump. Castrol followed with a 20w-50 during 1960
Believe me, they needed a 20w-50 lubricant - but it was really all about a very poor design concept and marketing gone wrong!!
The "A" Series engine in these cars always ran very well on a 20w-20 or 20w-30 lubricant in other applications
During the 1960s the 20w-50 viscosity quickly became the "fix-it"viscosity for poor design, leaky engines and etc. Of course it had other applications.
In Europe at this time 10w-30 had a great following and for example the VW Beetle ran very well on 20w-20 lubricants - Owners were swayed by Advertising and ran the new 20w-50
It has some applications but probably the real need is few and far between
Yes. I lifted it from
this thread, which was the first that came up in my search.
Maybe I'll try to find Doug again and bug him to tell us the history of the 20w-50 grade again. I seem to bug him to do that at least once a year, so I should be due again. I always like the history lessons.
