SLS wrote:
I never payed a lot of attention to antifreeze other than making sure I had enough to keep things from freezing. But these days I realize how important it really is. I'm going to switch to the AMSOIL Propylene Glycol Antifreeze and Engine Coolant a Super long life fluid - 750,000 miles/7 Years of service in over-the-road trucks & 250,000 mile/7-Year service life in light-truck and auto applications. Essentially nontoxic & biodegradable. Superior performance in all climates. Contains corrosion inhibitors & anti-foam agents. I'ts not cheap but neither is replacing my engine.
You should talk to your buddies and Amsoil and see if they can make a timing belt for our Jeeps that will last 300,000 or 400,000 miles so that we only have to change it at rebuilds. Everything else they make is orders of magnitude better than the "equivalent" products we use.
Propylene glycol simply has much lower toxicity than ethylene glycol. Ethylene glycol would be essentially nontoxic too if it wasn't imbibed.
Ethylene glycol breaks down in the environment more quickly than propylene glycol, so a claim for PG being better doesn't wash.
It also requires more PG as a percentage of the mixture with water than EG to obtain the same freezing point. One negative of PG is that it is substantially more viscous than EG at low temperature at the same concentations. PG is considered to have a higher heat capacity than EG, but more has to be added to get the same effect, and since water is actually the component with the highest head capicity in the system, then which of the two mixtures, PG/water or EG/water, has the better ability to carry away heat from the system if mixed in the appropriate proportions to be useful at the same exact temperature ranges?
Actually...I don't have anything personal against PG. I get annoyed, like the others, with the "use this product and save the world stuff." When it comes time do my flush and change, I'll take the advice of some of our truckers on this forum and use something designed for a wet-lined engine. I'm not overly concerned with whether the carriers is EG or PG, but just want to make sure I use something with the proper additives.
I don't dispute that Amsoil makes good stuff. I just don't think it's the 10 or 100 times better (that its fans purport) than the "equivalent" products most of us use. I currently run the Shell Rotella T synthetic 5w40 that I change every 10,000 miles. I'm sitting at 78K and the motor hasn't blown yet.
We tend to get into pretty intense discussions in regards to brand, variety, and viscosity of motor oils, for instance. And really, the most significant thing isn't what you use, it's a matter of having the correct amount in there at all times and changing it out periodically. Differences in viscosity, brand, variety are really only going to net an incremental improvement over anything else. The only way to really know how good one product is over another is to machine all of the parts in the engine exactly the same, drive 10,000 of those vehicles under exactly the same conditions, tear them down after a few hundred thousand miles and compare the damage. The singular data points most of us, me included, report are relatively meaningless. The best we can do is give a binary result: did the engine blow or does it still run? The guys who do the UOA's do provide some useful information in terms of showing potential trends, but in general those are string of single data points of snapshots in time that may or may not transfer to the rest of us.