Here's the results of the engine oil survey. First off, thanks to all who participated. Your information was much appreciated and invaluable to neophytes like me. So here's what you said: ENGINE OILS - WHAT IS THE BEST? Well, here is the results of the on line survey of what oils do we use in our "babies". Just to reinforce what an eclectic group we are, there were replies from everyone from owners of daily drivers to quotes from an engine builder for a Ford powered NASCAR team. The unasked question of "why use synthetics, seemed to reduce to a couple of pertinent points. 1. Synthetics are an engineered oil, so all the oil molecules are the same size. They do not require any additives so there is no additive to wear out prematurely. 2. Actual experience tells these experts that synthetic oil will stand up much better in the "non journal" areas of the engine, the 'hot spots' that the oil temperature gauge does not measure. The top favored synthetic oil is Mobil 1, by a wide margin, with Amsoil coming in second. The engine builder for a Ford powered NASCAR team (who incidentally uses a "special blend" they mix themselves for all their race cars) had just completed a $180,000.00 oil study to arrive at their "special blend.." They decided to run a new engine with Mobil 1 and one of their other engines with their "special blend" oil on both a dyno test and a single race. When they tore the engines down and compared results, they found the Mobil 1 engine was within 1% of the dyno results and the wear results of their other race engine. Pretty good endorsement, since their "special blend" costs $1,000.00 a quart! Not sure if they still use that special blend.. There are many conventional oil fans, particularly in the daily driver and non race driver category. Many told stories of tremendous success and high mileage with no problems using conventional oil. Their favorite oil was Castrol GTX, followed by Havoline and Penzoil. One individual reported "I use anything that is on sale." So one could well ask, "how bad is any non synthetic oil?" It would appear based on the survey results, that conventional oil (Castrol GTX in particular) is the best oil available in non race situations. The people who used this oil in their daily drivers or show cars (including 428CJ's) found it to be an excellent oil. No one that reported , used conventional oils in their occasional racers. More than one mentioned that Quaker State oil is a no go; it is a high ash oil that leaves excess engine deposits. All of the racers, either occasional or serious, and some who had Boss 302's and 428 CJ's that saw only street duty, swore by the synthetic oil, with Mobil 1 being the top choice. I asked one of the experts, "so why use synthetics if I don't race my car?" He answered this way. "Based on race experience where we used synthetic oil exclusively, Mobil 1 is the best." He also said that he used Mobil 1 in his daily drivers. When questioned why he would use synthetics that are 4 times the cost of regular oil, he replied "cheap insurance and improved gas mileage". He claims that Castrol GTX costs him $2.19 a quart and he can buy Mobil 1 on sale for $3.50 a quart at Target. The $ difference in an oil change is minuscule. All synthetic users recommended that on a new engine, to break it in first (although I believe Audi and GM now use synthetics from new and recommend oil changes in the 6-9,000 mile range). Once the car has 1000 to 1500 miles on it they recommended a switch to synthetics. They also cautioned that using synthetics on an "older engine" might cause leaking past the seals. But on newly rebuilt engines, go with synthetics once past the break in period. The purpose of this survey was not to change anyone's mind, but to simply report what some of the experts have to say about synthetic vs. conventional oil. On a personal note, Castrol GTX worked really well in my Shelby GT-500 and I would still be using it if we still owned the Shelby. But on our newly rebuilt 351W in our 1969 Mustang GT Convertible????? Watch for an update on this one..
