Synthetic oils

I've been running synthetic oil for several years in our entire fleet. We don't change oil every 15,000 miles though. We change oil when it needs to be changed which is usually about every 200,000-300,000 miles. Yes, you read that correctly. We run a bypass filtration system on every truck and do oil sampling every 15,000 miles when we change the bypass filter element.

 

We started running the amsoil synthetic oil with the filter bypass system back in July in our freightliner. We have not had a need for an oil change as of yet. We will change it when needed according to an oil analasis. We are happy with it so far, the truck seems to run a bit smoother. It is really nice not to have to do oil changes so often.

 

WOW! I'v looked at those systems but didn't know if the claims were true or not.

My concern with synthetic ils is that they seem to leak from everywhere if you run them in a high mileage motor that has ran conventonal oil. I run synthetics in all my personal vehicles but I had a MErcdes diesel car I bought with 280k on it. I put synthetic in it and it started burning ALOT of oil, it burned a good bit of regular oil but it was sucking down 3 quarts a week of syntetics and that's too pricey to pour out the pipe. That motor needed rings though. I have heard that the motor will consume more synthetic at first but the syn will actuall clean out the ring groves and overtime the consumption will lessen, just a matter of if you can afford to dump that much synthetic oil.

 

Amsoil is the best oil by far.... (my opinion but they do have independent test to show results). I ran it in my Truck when I was a O/O.. didn't really have it long enough to really tell you results.. I did notice a "small" increase in fuel mileage by using Amsoil...

I use it in all my vehicles...

 

I use Amsoil sythetics anywhere there is oil in my truck, as well as the power steering gear. The Series 3000 5w-30 Heavy Duty Diesel oil is great. I change at 50,000 intervals, with a filter change at 25k.

15k intervals are ridiculous. Many fleets change at 25k. You can go longer than the 50k that I do, as others have mentioned. Just get a bypass system from Gulf Coast Filters, or one of those FS2500's. Amsoil also has a system that's cheaper than both of those, but doesn't have the filtration capacity. Although, it does have spin-on filters, which would be much less hassle.

Things that improved for me with the use of synthetics?

-Engine runs cooler. When I got my truck, it would get hot under load and climbing hills. The fan would kick on. Now? Rarely ever.

-Fuel Mileage went up. I did a few things to improve this area, but I think the biggest benefit was the synthetics. Immediately saw a 3/10 mpg improvement, which steadily got better. I average 7/10 to 1 full mpg better since I switched over all my fluids to synthetic.

-The cost. While it may roughly be double the cost of a standard oil change, it will last you double the time-or much longer. Not just money-wise, but time wise as well. Changing oil every 15-25k means time in the shop. Even the Speedco's of the world are still going to cost you an hour of your day.

-Engine life. Running synthetics is better for your engine. It will have much less wear, which means that in-frame rebuild can be put off for a while. As with my situation, the engine also ran cooler. Less heat will also mean longer engine life along with the accessories under the hood.

I had an '87 5.0L Mustang GT that I ran nothing but synthetics in for 109,000 miles of hard driving. When the car was totaled, I sold the engine. But before that, we tore it open to see what the bearings and insides looked like. The motor was clean-no sludge anywhere. Everything looked new. That changed my mind forever on synthetics, and I use them on everything-including my lawn mower. By the way, that Mustang GT also got 26 mpg on the highway, and sometimes up to 30 when I wasn't driving like a madman.

 

I'm not an O/O, nor do I own a truck of my own.

But, I have used synthetics for over 20 years. I was one of the first in our area to jump on the AmsOil train. My friends thought I was nuts. It took less than 30 minutes for me to come to the conclusion I NEEDED it in everything I drive/ride.

With the correct use and filter changes, you can gain a lot from the use of synthetics. You save money, increase the life of the engine, and reduce the downtime when you have to do a rebuild (less clean-up needed).

MedicineMan: Synthetics aren't recommended for high milage engines that have not used it from the start. It causes problems you described, because of excessive wear already on the engine. Take heart though, Castrol and others have developed a synthetic especially for high milage engines

 

Is there any drawbacks to Synthetics?

 

the only drawback like mentioned is that you can't put them in a motr that is high mileage and hasn't used them. SOme would say the cost but with being able to extend the oil changes they moake up for that too. Now if you still change the oil just as often then yes they are too expensive.

There has been some debate over the quality of amsoil and royal purple. but amsoil is in use in a large number of trucks. I run royal purple in my jeeps and I love it but there is debate over that perticular oil becuse it has teflon or graphit or something in it. I know cummins absolutely forbids royal purple use in there motors so even though I have used it for years I think I'll be using amsoil in th trucks

 

I own a 99 Silverado with a 4.8 liter LS1 I bought it used when it had 60,000 miles on it. The previous owner said he always used synthetic oil. Anyway when I tried conventional oil in it it sounded like the lifters were messed up. Click click click or tick tick tick. So I put Mobile one in it and it purrs like a kitten.