As I was perusing my Bentley manual I noticed that he says motor oil "used in 
1975 and later cars must be labeled 'For Service API/SE'".  What does this 
mean?

I checked the PENZOIL GT Performance 20W50 I'm currently using and it says 
API Service SH, SG.  An older case of PENZOIL 20W50 I had kicking around 
(doesn't way GT Performance on it) says API Service SH, SH/CD, SG, SG/CD.

So here are my questions:

1) Anyone know what the difference between PENZOIL 20W50 and PENZOIL GT 
Performance 20W50 is?

2)  What do all these API Service acronyms stand for?  SE?  SH?  SH/CD? SG? 
SG/CD?

3)  Am I using the wrong type of oil?  

Thanx.

-- 
+------------------------------------------------------------------+
| Glen Buhlmann            | I know it all.  I just can't remember |
| GB Computer Consulting   | it all at once.                       |
| Burnaby, BC              |                                       |
| gbuhlman@direct.ca       |                                       |
| '77 VW Westfalia         |                                       |
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| http://www.geocities.com/SiliconValley/5288/                     |
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