Hello, I have been running synthetic oil in my car for a few years and I am wondering if the extra cost is worth it. I also have noticed that the rear crank seal seems to me to leak worse with synthetic oil. It has the Caddy seal, the one that has to be fitted. It has the called for crush and a little sealer in the groove behind it and ends are offset about 3/16" from block surface. I think this is the third seal I have had in it over the years because of rebuilds or because motor was out for other things I changed seal trying to stop the leak. I mainly use the synthetic thinking I might get a little more protection if motor ever gets to hot or something like that and have read that newer oils are not as good as they used to be for motors with slider cams, maybe that is all bull, I don't know. I am wondering what some of you people think on the subject, and if it is true that new oils are made for roller everything in new motors. I have also noticed that the synthetic gives me a little better hot oil pressure at idle at a stop sign but that probably is not really an issue. Thanks for your time, Tom W:Comp:
In my opion you can not go wrong with synthetic engine oil.I have personaly wittnised 2 busch grand nation egines i took apart that saw over 300 deg water and oil temp and the bearings looked fine.Yes for some reason the synthetic will leak more but i have personaly have not had it happen to me.And alot of your new oils are for roller cam engines that are being produced today so you have to watch the markings on the oil to make sure it is compatleble with flat tappet cams. mike
I use synthetic in any engine I care about. The 454 in my boat was worn-out when I bought it, I've been using 15-W40 diesel (and gasoline) rated oil in it. Much higher levels of anti-wear additives than in the new formulations of "car" oil, but still much less expensive than synthetic. The trick is to find oil that's rated for both diesel and gasoline engines. You can tell, the diesel rating on the container starts with "C", for "compression ignition" as in "CD", or "CF", or "CG" or whatever. The gasoline rated oils start with "S" for "spark ignition", SE, SF, SG, whatever.
Hi, Thanks for the replys, What I heard about the new oils must be true then. I will stick with the synthetic since it has been run so long with it and have to live with the rear main leak. The leak seems to be the worst after a day of drag racing, maybe on launch the seal gets flooded with more oil than it can handle. I still have the stock pan and baffle with a scraper maybe a bigger pan with some type of baffle in the back would help the leak? My stock balancer always leaked a little to but that stopped after going to a BHJ which doesn't have the little grooves in it where seal runs. I have also been told that synthetic oil will eat up the stock rope seals, anyone else ever heard this? Tom
I've owned my 425 since 1976. I will tell you that rope seals SUCK. I've tried many different things with them, from packing them in tight to soaking them, and they always wind up disentegrating and end up sucked into the oil pick up screen. I refuse to ever use one again. I will use a previously enjoyed neoprene seal 3 times before ever putting any rope seal into any engine ever again. I use synthetic in my engine, and have also noticed better hot idle oil pressure. I also use it in my power steering and that works quieter and smoother too. I also use it in my rear end. (no, not that one!:grin: ) I can't decide if I want to put it into an original tranny with over 250,000 miles on it though. Maybe after I rebuilt it with new clutches I will. I love the stuff!!!:Brow:
Schurkey, Thanks for the info. I did not know about the S for spark and C for compression. I like the idea of using this in an older well used motor especially if it already has oil leaks or it still has a rope seal. I like synthetic in any motor that is going to get pressed hard or one that I plan to keep a long time. Especially if the engine is new. I have not tried or even gotten comfortable with the idea of using synthetic in a transmission. I use it in the motor and rear. Never even knew you could use it in the power steering. Also since synthetic is thinner and slicker for the same weight and I don't like oil leaks. I use the thicker synthetics for vehicles that are primarily used on the street. The oil leak and loss of protection margin is not worth that last 1 hp for the thin stuff to me.
Most people don,t know this but your new cars come from the factory with synthetic thur out the drive train engine,trans,rear my 2002 blazer came that way. mike
