CAN ENGINES BE TOO OLD FOR SYNTHETIC

[SLOBuds]

I have had a couple of experiences where synthetic (most likely) caused changes to my engines oil usage. My experience and all of the similar reports sort of allude to the possibility of experiencing leaks after the change. The leaks being caused by some type of 'cleansing' action within the synthetic itself.

It is near impossible to attribute the synthetic oil to the leaks. But in my case the leaks (and top end blow-by through valve seals) were close enough to my switch to synthetic changeover that I am sure it was the cause.

The synthetic guys say that it isn't due to the oil, but due to the bad gaskets and I should change my gaskets. I think that is an empty argument because the gaskets don't leak with dino and there is no compelling reason to change oil types if I am not going to save money with the change. Or, they would have to show me that I save money ON TOP of my expense to replace my seals and gaskets.

Other than that, which apparently is a condition that not everyone experiences, I do like synthetic oil and use it whenever possible. I change oil once per year, regardless of miles. 240k miles on an Avalon using synthetic. 100k on a Ford Ranger.

 

[Soundguy]

Another reason I might not use synthetic on an antique or classic machine gas or diesel is due to fuel contamination of the oil.. I'd ahte to toss expensive oil cuz it had too much diesel or gas in it from an old worn carb.. or hard starting low compression diesel.

soundguy

 

[cmuncy]

About 8 years ago when I had enough of IT and got into working on diesel trucks, we had a lot of experience with synthetics, especially with Amsoil.

It seems that Amsoil has a detergent in it to clean out the "crap" that you'd expect to find in all of the nooks and crannies on engines.

Even after flushing an older engine with the engine flush ( talking about a bad smell: ranks right up there with friction additive for rear ends.... on trucks...) we had issues with turbo pedestals leaking oil around the orings.

One thing that we did on all synthetic conversions was add a single or dual stage bypass filter. Worked great. We would see trucks with 10k on oil and the oil still looked like corn syrup.