clean oil...is that good?

 

While I'm not going to defend anyone that changes synthetic at 10,000 mile intervals (I'm a dino 3 month / 3,000 mile kinda guy) I do know that the higher end vehicles (BMW, Porshe, etc..) have a sensor that monitors oil breakdown and viscosity. Some if these cars are going 9,000+ miles on dino oils before an oil change is indicated. Knowing this I can't think of any reason you wouldn't be able to get 10,000 miles from synthetic.

You might find this funny. My dad uses uses the synthetic oil (Castorl Syntec) that he drained out his car for the riding lawnmower. He changes the oil in the lawnmower once a year.

 

You can use Synthetic on a vehicle with 91,000 miles, you just have less investment to protect and a greater chance the seals won't hold it in.

Synthetic has proven over and over again to be a better oil to use in your vehicle. There are three downsides though, cost, warranty, and oil leaks.

You can make up the cost by driving more miles. 5,000 miles seems to be as common for synthetic as 3000 is for conventional oil. You just don't want to exceed the mfg suggested limit which is think is 7,500 miles while your vehicle is under warranty. As for leaks, try it and find out.

I put synthetic in my 96 Voyager (92k) last winter and found oil spots on the garage floor. I went back to conventional and they went away. If I want to use it in that vehicle I know I'll need to replace a seal first. Probably that seal will leak the conventional oil in the near future and I'll have to replace it anyhow.

If the wheather gets to -30, then using synthetic is cheaper than having a car that won't start.

The forth down side is who is driving the vehicle. I have two trucks two cars and a mini van on the road, driven by myself, my wife, and two teenagers. I'll run synthetic in my truck, but I would rather have the others changed every 3000 miles, just so that the hood gets opend once in a while.

This logic applies to a lot of drivers today. 3,000 miles is a reasonable distance to go without checking your oil. 5,000, however, isn't, and if you are a little late on it, 6,000 is asking for trouble.

Which reminds me, I better take a look that Concord with 163,000 miles driven by a 16 year old.

I would say go for it. It's so easy to change the oil on an F-150. No jack or stands needed. Change it in April and October. If the seals won't hold it, you go back.

 

I just looked at my Amsoil catalog & found that Amsoil recommends 25,000-mile/1-year drain intervals with a filter change at 12,500 miles (Amsoil filter).

Hmmm, I just might switch to synthetic.

 

The only reason why you wouldn't want to use a synthetic in an older vehicle is the capacity for leakage. If you have a small oil leak...you'll have a bigger one after the change. As far a seals go, all modern synthetics are seal friendly.