I have a 1997 F-150, 1997 Taurus, and a 2001 Grand Prix. The Fords are over 120,000 miles each and the Pontiac is at 81,000. I have owned all 3 since their very very early days (but not new). My oil (always Castrol GTX) has never been in a block longer then 3500 miles ever. I ran AmsOil in the F-150 for awhile and ran many more miles on it then. All 3 are in top notch running condition, no smoke, no leaks, and all sound great.

My question is with this many miles on the engines, is it still worth the expense of using snythetic oil in them or is what ever wear is the there is there so its a waste of money?

Thanks,
Jeff

Jeff,

Wether or not to use synehttic oil is not really dependant on the mileage or age of the vehicle, but of it's condition and how long you plan to keep it.

If you keep you vehicles the "normal" 3 years or so, then I would say that synthetic lubricants are most likely not worth your trouble.

If you do like we do in our home, and buy good used vehicles and drive them until it's time for the crusher, then yes I feel they are a real benefit.

That not withstanding, you can save up to 5% on your fuel use, and over the years synthetics actually cost LESS because there is absolutely no need to change oil every 3,000 miles. 7500 mile intervals with a GOOD synthetic oil (like Amsoil) are more than adequate for most people.

Thanks for replying. We do drive them until they get to a point that no yu can but thats not from lack of care, just age. I have no problem spending the time and money to keep them running right (hense the 3000 mile oil changes :screwy: ). I will start using snythetic at the next change.

Thansk again,
Jeff

You are welcome, glad to help.

Do not put synthetic in the newer engines or the lifters will rattle.My neighbor's wife did that,changed to synthetic in a 1998 or 1999 S10 and the lifters rattled like crazy.She did drain out the synthetic out and put in what is recomended,the lifters quieted right up.Put in what is recomended.

I'll call BS to that.

Any synthetic oil will replace ANY "dino" oil w/o any problems what so ever.

Now, can you put 0W-20 synthetic where the manufacturer calls for 10W-40? No, I would not suggest that.

Typically, a good quality synthetic oil will FIX noisy lifters after a period of time, because (good) synthetic oils do an excellant job of cleaning varnish and deposits from the engine.

That is true story and synthetic will not fix noisy lifters all the time.Like my mother's 2006 Chrysler 300C,it call for 5w 20 motor oil only and it says on the oil cap and that is what is going in and NO synthetic.

About the only way you can get in trouble with synthetic oil, is putting it in a high mileage engine that has not had proper maintenence. Engines that havent had regular oil changes, or that have had cheap oil used in them, will tend to be full of sludge and carbon deposits. The detergents will start doing what theyre supposed to do, and clean the inside of the motor. If the motor has alot of carbon deposits, sludge, gum , and varnish, this can break loose and stop up the return holes in the heads, and the oil pump pickup screen. High detergent petroleum based oils can cause this also. Sounds like youve done regular maintenence, so you shouldnt have any problem.

I am a dealer of Amsoil products and in my 20+ years using them I've not had any problems whatsoever. Yeah, I know that's easy to say but I also realize I was also once a spectic. I've used the oils in high mileage engines and new engines without having any negative experiences and neither have others I've known to use them. As for an engine with high mileage and poor maintenance, my own personal experience is, yes, the oil did clean the engine but where the engine initially consumed one quart per 500 miles the consumption dropped to nearly one quart per 1k miles. There have been other noticeable improvements beyond the reduced consumption including smoother idle, more power, better fuel economy and so on. In my newer engines, I've used the 0W-30 and have had no problems either and have put over 80k miles since. I also daily drive a 1995 Olds that has over 140k on it and it runs great. If you have any doubts and are using the Amsoil, you can also give them a call and talk to one of their techs who will be willing to help. I know most people bash the use of synthetics and like I said I used to be spectical about them but I did some research and also gave them a try knowing I could always switch back but in my case I've yet to find a benefit to switching back.

Goose, do you run AmsOil? If so do you run it for 35,000? I ran it once for about 17,000 and the urge to change the oil got the better of me.

Yes, I run my oil within the specs they claim whether its 35k miles or one year and I change the oil filter ever 12.5k. It usually boils down to change the oil once a year and the filter in between. I know that many get skiddish about running it like they say but I'm not hearing of litigations against them and only once have I heard where they ended up replacing a motor.

Thanks Goose.