Well, I'll bet most people don't really give a rats rear end about what oil I use either, but here goes. I'll start by saying that from the time I did my first oil change I have always bought Penzoil. In my old Imperials I use straight SAE30W. In my modern V8 cars, that means 1980 and newer, I use 10W-30. I have one 1980 car that has a worn engine, so I use 20W-50 in it. I also use 20w-50 in my '56 Imperial since it is pretty tired as well, but I am now thinking of changing that one to SAE40W, since I think it is actually heavier. I also have an old Continental with a tired V12. My fellow LZOC members all caution me to totally avoid ANY use of multi-viscosity oil in it, especially with that old engine. They have insisted that I use straight SAE30W. The '68 that I just bought has been getting 20W-40 from its previous owners, so I planned on continuing that once I change that dang starter and am able to drive it. The climate here isn't great for crawling around under the car unless it is parked at least on a cement slab, and preferably in a warm garage. That car presently is not in or on either one. I guess that I should add to all of this that I have never blown up an engine in an estimated total of about 2,200,000 miles of driving since 1968. The engine in one of my parents car's siezed after I drove it in 1970, but that was because my father had neglected a blown head gasket that put a two quarts of anti-freeze into the crank case over a period of six months. I also was too young and stupid to have a clue that anything was wrong, although I don't recall any actual symptoms while driving the car. These days I would be alerted to this by seeing the nasty concoction driping off the dip stick while checking the oil. Cheers! Paul In an email dated Sat, 4 12 2004 5:15:50 am GMT, "Dick Benjamin" <dickb@xxxxxxxxx> writes: >>>>>Straight 30 weight? I usually use 10W30 or 10W40, as per the manual on >my > >'70. ?Why would these be considered the wrong oils? Is it just because this > >car is worn? > > > > > >I don?t have a manual from a'70, but what you say surprises me. > > > >10W30 is very thin oil, especially for a car with 35 years of use on it. ? I >use SAE30W in all my old cars, but my choice is somewhat influenced by where >I live. ?Our temps almost never go below 32 degrees, and SAE30W was the >recommended oil for that environment, even when the cars were new. ?A more >worn engine requires heavier oil to maintain proper oil pressure. ?See what >the factory says about this - - - > > > >The following is quoted verbatim from the 1972 FSM (the capital letters are >theirs, not mine!): ?"IMPORTANT: ?If the vehicle is to be used for maximum >performance service (very high speed or very rapid acceleration), the engine >requires heavier than normal lubricating oil. ?This is due to the high >speed, loads, and temperature of moving parts developed in these engines >during this type of operation. "FOR BEST PROTECTION OF THE ENGINE UNDER >THESE CONDITIONS, THE HEAVIEST AVAILABLE ENGINE OIL OF SD OR SE QUALITY >SHOULD BE USED THAT WILL PERMIT SATISFACTORY COLD STARTING. [these are >obsolete quality ratings, today we would say SJ or SI] > > > >SAE 30 AND SAE 40 ARE RECOMMENDED [then it goes on to discuss multigrade >oils, which are also permitted, if 20W40 or 20W50 is used, with a special >"high performance" additive (STP?). > > > >For many years, some car manufacturers, and most heavy equipment >manufacturers advised against using multigrade oils (the viscosity index >improvers are not lubricants - My understanding of the reason is that they >are simply thickening agents, so when the lubricant is under great stress >(high temp, high loads), the coefficient of friction is higher than with >straight weight oils. ?I also have some antique heavy equipment (dozer, >backhoe, skiploader etc), and those manuals are very emphatic about it. > > > >In my modern cars, I don?t agree with the recommended 5W30 oil either. ?I >believe the car manufacturers specify very thin oil in an attempt to satisfy >the CAFÉ requirements - they don't give a hoot how long the engines last, as >long as they go beyond the warranty period. ?I switch to 10W30 after the >first oil change - and when the cars get older, I'll probably go to a still >heavier oil. I do use multigrade in the new cars, because I know they were >designed to tolerate it better. > > > >Enough of my biased opinions - suit yourselves, guys. > > > >Dick. > >-----Original Message----- >From: mailing-list-owner@xxxxxxxxxxxxxxxx >[mailto:mailing-list-owner@xxxxxxxxxxxxxxxx] On Behalf Of Rob P >Sent: Friday, December 03, 2004 6:54 AM >To: mailing-list@xxxxxxxxxxxxxxxx >Subject: RE: IML: 1968 Check Gauges light/Oil Pressure > > > > > > > >>From: "Dick Benjamin" <dickb@xxxxxxxxx> > > > >>There are other possibilities, such as the wrong oil being used (you should > >>be using at least either straight SAE30W or 15W40, depending on where you > >>live, low oil quantity, or a worn oil pump. > >> > > > > > > > > > > > >----------------- ?http://www.imperialclub.com ?----------------- > >This message was sent to you by the Imperial Mailing List. Please > >reply to mailing-list@xxxxxxxxxxxxxxxx and your response will be > >shared with everyone. Private messages (and attachments) for the > >Administrators should be sent to webmaster@xxxxxxxxxxxxxxxx > >To UN-SUBSCRIBE, go to http://imperialclub.com/unsubscribe.htm > > > > > > ----------------- http://www.imperialclub.com ----------------- This message was sent to you by the Imperial Mailing List. Please reply to mailing-list@xxxxxxxxxxxxxxxx and your response will be shared with everyone. Private messages (and attachments) for the Administrators should be sent to webmaster@xxxxxxxxxxxxxxxx To UN-SUBSCRIBE, go to http://imperialclub.com/unsubscribe.htm