Does it make a real difference to use synthetic oil in an old 1985 car?

I am just trying to decide if i use synthetic oil in my 85 bmw next time I change the oil. I was told that is better, but no one can really explain to me why.Does it make a real difference to use synthetic oil in an old 1985 car?
I agree with Ian F. The new synthetics not only stay cleaner, but they will loosen and remove gunk left by the old petroleum oils and you will probably end up with oil leaks and burning oil.





Synthetics are DEFINITELY better lubricants, but on an older car, most of the engine wear has already occurred so you wouldn't be gaining much aside from the lower viscosity in the winter and lack of new sludge forming in high summer heat.





I've used Mobil 1 in my 1989 Trans Am from the start and my mechanic says my engine is still clean inside.Does it make a real difference to use synthetic oil in an old 1985 car?
Just my opinion.





If you've been using conventional oil for years without any problems, keep using it.





My Chevy truck has over 240,000 miles on it and conventional oil has worked for me just fine.





That being said, if you buy a new car, I recommend using synthetic from day one.
It's supposed to last longer, and may lubricate better. The former is a lot more certain than the latter.





The only problem is, in an older car, your seals might be getting a little on the old side, and any radical changes in oil composition might loosen sludge or harden or soften seals, and you could start leaking oil. You'll never know for sure what'll happen until you do it.





But if you've made it 23 years on natural oil, I think that should tell you something.
Personally I don't think so. I have use castrol for 25 years. Never had a problem. No oil gunk in my motors
it seems in my experience it is more important to use a high quality filter to keep dirty particles out of the engine. even with a snythetic oil you should change at 3-5k miles anyway. i think most mechanics would probably agree.
I think the best benefits would be had by using synthetic in a brand new car and continuing throughout it's lifetime. To use it in an older car, it might still retard wear and possibly help (slightly) with gas mileage but I think benefits would be only marginally better. (My opinion)
it is just a personal choice you have to make. but with an older car it might cause some problems with a sudden change. it does last longer and suppose to lubricate better.
synthetic lubricates better and you can go 6 or 7,000 miles between oil changes, the only thing is it's expensive and if your car uses any oil or leaks any it will use it a lot faster.
It's bull crap that synthetic oil will harm your engine or seals. It is better for your engine because of its shear composition, flash temperatures and vaporization. HOWEVER, what is it you are trying to accomplish? If your goal is not to set a record for high miles and you aren't planning on keeping it for over 2 years then you could be spending more money then you actually need to. Of course your oil change intervals can be extended more ( Mobil 1 has those specific mileage brands ), though I wouldn't recommend extending it for more than your manufacturers light duty schedule.
Generally it is slicker and lasdts longer, but it is usually lighter weight (5w30) for an unworn engine, so I'd go with a convential heaveir oil like (20w40) weight.
The general idea behind better lubrication from synthetic oils (I'm thinking of Mobile-1) is that all the molecular chains are about the same length, so the shorter ones don't vaporize and the longer chains are not left behind as sludge. That generally means better lubrication and longer intervals between oil changes, although the manufacturers will still hold you to the recommended oil change to keep your warranty valid. If your engine leaks internally or externally, synthetic oil will quickly find a way out, especially if you use a lighter grade. That's another way they save fuel. Any lighter weight oil is slicker and the original synthetics were 5w-20. They were recommended as an exact replacement for 10w-30 or 10w-40.