I did a quick search and came up with nothing. I just bought a Chrysler Conquest with 120xxx on it, and it needs an oil change bad. I wanted to know if switching to synthetic this late into its life would hurt it or benefit it. I have always run mobil one/royal purple in all of my vehicles but have never had one over 60k. Thanks !!!
If it already leaks engine oil it’ll leak worse. Otherwise it should be fine.
no leaks as of now, bottom of the car is bone dry!
well spray some oil on there so it doesn’t rust then
how about i get it undercoated it at work for free plus tip lol
I can’t see the benefit justifying the cost unless you are going with an extended oil change interval. That’s the same way I see it with new cars too though.
well it doesnt break down and seems to actually keep the enigine cleaner. Well that could have also been the nitrous on all my other cars too 
I’ve heard valvoline maxlife is great for older engines. It’s a synthetic blend. Should easily be able to run 5-7k+ miles on it.
[quote=“BrockwayMT,post:4,topic:38601"”]
well spray some oil on there so it doesn’t rust then
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I have some spare old oil if you need it! Ha Ha!
Synthetic is all i run in all my autos.
its 120,000 mile car just do a high mileage oil change synthetic is not needed
^^
agreed… I wouldn’t switch to synthetic, you have no reason to apart from blowing more money in this case. it ran fine for the first 120K without it, right?
I would run a Synthetic blend. Its really up to you.
Synthetic can stand up to more abuse regardless of how many miles on the motor.
Run Mobil 1
Mobil 1 high mileage is your best bet.
In my mind, mileage doesn’t matter. Yes if you have leaks with petroleum based oil they will not get any better and might get worse with synthetic. Aside from that, better lubrication is better lubrication. Why not take steps to slow whatever wear on moving parts will happen in the future? I mean, if you’re dry palming it and suddenly remember you have vaseline do you say “naw, I’ve been rubbing it raw thus far it won’t feel any better to lube up now.”? No, you don’t. Same goes for your engine.
:lol:
[quote=“HYBOOST,post:9,topic:38601"”]
I have some spare old oil if you need it! Ha Ha!
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You’re not supposed to use used motor oil as the acids in it make the rust worse. I recommend ATF cut with about 10% diesel so it sprays better.
FWIW Redline and Amsoil are generally regarded to be the best oils on the market. Mobil 1 reforumlated with some sort of a lesser grade of synthetic base. I’m not real clear on the details as I don’t know a whole lot about motor oil chemistry, but it’s still a full synthetic and still a good oil, but not in the same class as the first two I mentioned. Whether that means they’re worth 8-10 bucks a quart is up to you.
[quote=“Violator,post:14,topic:38601"”]
I would run a Synthetic blend. Its really up to you.
Synthetic can stand up to more abuse regardless of how many miles on the motor.
Run Mobil 1
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Most API SM GF4 motor oils are semi synthetic.
I’d try motorcraft/kendall… Those are a great value.