Switch to synthetic?

PR5speed

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2002 Mazda PR5
I have almost 103K miles. Only conventional oil has been in it.

I've had a few people tell me that if I switch over now, it will **** up the engine.

Is this true? has anyone else switched over at high mileage w/ a MP5?
 
i just switched over at 80k and its still running fine. i think ive done around 3k since the switch and ive lost no oil at all and it still looks pretty clean (checked it last night)
 
Maybe you can try semi-synthetic then if all goes well go for full synthetic on the oil change after that. Although I've never heard that going from non-synthetic oil to synthetic oil will ruin your engine...

Perhaps this bit of the wikipedia article on synthetic oil will clear things up.
 
I have almost 103K miles. Only conventional oil has been in it.

I've had a few people tell me that if I switch over now, it will **** up the engine.

Is this true? has anyone else switched over at high mileage w/ a MP5?

I switched when I got my car at 85k miles and had no problems. Just make the switch - anyone who tells you that it's gonna ruin your engine just heard that from someone else who told them that it'd ruin their engine. It's a load of bull.
 
I have almost 103K miles. Only conventional oil has been in it.

I've had a few people tell me that if I switch over now, it will **** up the engine.

Is this true? has anyone else switched over at high mileage w/ a MP5?

I would change to a specific high mileage oil if I were you. I'm about to do the same thing if I can find a full synthetic one.
 
I've heard the same thing from several people. I bought a used 2002 with 112,000 miles on it and switched to Amsoil. I change it once a year and the car runs great!
 
switching from synthetic to conventional should be done in stages, but is still possible. Slav is correct however, a conventional run car can at any time without consequence use synthetic. If anything the extra additives and lubricating properties will help the car run better. 20-30 years ago it was an issue since conventional oil was bad enough and engines ran poorly enough to create good amounts of slugde, so that when people ran acutal synthetics in their car it would kick s*** up and possibly clog some oil line. Conventional oil is so far ahead of what it was even 10 years ago that unless the P.O. liked to run 15-20K OCI on walmart no-name brand, rev the piss out of the engine as his daily trip to work and re-use oil filters you're safe.
 
I switched when I got my car at 85k miles and had no problems. Just make the switch - anyone who tells you that it's gonna ruin your engine just heard that from someone else who told them that it'd ruin their engine. It's a load of bull.

That's good to hear. The person who told me actually is a friend from work - Our **** head GM had done this to his BMW a while back and asked my friend how much it would be to rebuild the engine. - My friend said that this was w/ any car though... Which is why I'm asking on here.

Conventional oil is so far ahead of what it was even 10 years ago that unless the P.O. liked to run 15-20K OCI on walmart no-name brand, rev the piss out of the engine as his daily trip to work and re-use oil filters you're safe.

Nah - ever since I've had it it's had name brand oil.. I'm pretty sure the previous owner always had name brand oil in it too, since he usually took it to the oil change place. (I got it 5000 miles ago, and have changed it twice - when I got it and 3k later)

Oh, ever since I've got it I've been putting in lucas oil stabilizer as well.
 
That's good to hear. The person who told me actually is a friend from work - Our **** head GM had done this to his BMW a while back and asked my friend how much it would be to rebuild the engine. - My friend said that this was w/ any car though... Which is why I'm asking on here.



Nah - ever since I've had it it's had name brand oil.. I'm pretty sure the previous owner always had name brand oil in it too, since he usually took it to the oil change place. (I got it 5000 miles ago, and have changed it twice - when I got it and 3k later)

Oh, ever since I've got it I've been putting in lucas oil stabilizer as well.

(squinty)
don't..there is absolutely 0 reason to use any kind of oil addative, unless you're looking to just trash the car in a few months or run it into the ground. If the car burns oil, probaly time for new rings.
 
I switched when I got my car at 85k miles and had no problems. Just make the switch - anyone who tells you that it's gonna ruin your engine just heard that from someone else who told them that it'd ruin their engine. It's a load of bull.

yea pretty much. i bought mine at around 86k and put synthetic in it a week later. been fine ever since (almost at 100k)
 
I always had mineral oil in my cars. Last year, at -35c,(screwy) car won't start. Battery is fine everything electric is ok. But man the engine was stone cold like an ice block. Finally started...but oh man powerful vibrations, took off slowly..then...BIPBIPBIPBIPBIPBIPBIPBIP!!!! an alarm!!! like an engine alarm!! I panicked, and stopped the car right towards a huge snowbank...let the engine run there for 5-10 mins..then I took off and it was ok...

So last week I changed my oil for syntetic..searched a bit for viscosity loses at low temps. Found out amsoil was best...but $$$..So I went for Quaker State Ultimate syntec 5w30. I want some crazy cold mornings to try this out!!
 
I always had mineral oil in my cars. Last year, at -35c,(screwy) car won't start. Battery is fine everything electric is ok. But man the engine was stone cold like an ice block. Finally started...but oh man powerful vibrations, took off slowly..then...BIPBIPBIPBIPBIPBIPBIPBIP!!!! an alarm!!! like an engine alarm!! I panicked, and stopped the car right towards a huge snowbank...let the engine run there for 5-10 mins..then I took off and it was ok...

So last week I changed my oil for syntetic..searched a bit for viscosity loses at low temps. Found out amsoil was best...but $$$..So I went for Quaker State Ultimate syntec 5w30. I want some crazy cold mornings to try this out!!

You'll get what you pay for with Amsoil. The Quaker State costs less, but can you go 12 months or 25,000 miles in a year with it? The protection from Amsoil is great, but the extended drain intervals are what make it the best bang for the buck. I guess it's not such an issue with the P5 since it hardly takes any oil(thumb). I really see the savings with my truck. It's a diesel and it takes 15 quarts.....:eek: Changing that once a year is nice.....
 
You'll get what you pay for with Amsoil. The Quaker State costs less, but can you go 12 months or 25,000 miles in a year with it? The protection from Amsoil is great, but the extended drain intervals are what make it the best bang for the buck. I guess it's not such an issue with the P5 since it hardly takes any oil(thumb). I really see the savings with my truck. It's a diesel and it takes 15 quarts.....:eek: Changing that once a year is nice.....

hardly take any oil? At least 1 quart between 3000 miles changes, and in our climats, you can't go 25 000 miles between oil changes. I don't know where you take your numbers, but you are completely off the track. Here in summer you can have temps over 40 celcius and in winter it can go -40 celcius, we have fog, rain, humidity...roads are like war zones. It's the worst environement for a car.

25 000 miles...wow...I want the name of your dealer man.. With amsoil, one of my friend in his 2000 jetta 2.0 can't pass 5000 miles without oil being black and used up..And his car is in pristine condition.

One other friend, had a pontiac sunfire, for 2 years, all he done to it is add oil when it needs it..When the head gasket fail, we dropped the oil...I never saw oil as thick as that!

Change oil every 3000 miles, change the oil filter, and you will avoid 99% of engine problems. Here it works like that. Maybe in your part of the world, it's something else, but I don't live there.

(monkey2)
 
I concur with the above comments (mostly)...I would go semi before going full synthetic, and there are plenty of awesome semisynthetics out there. I just switched to MaxLife Blend and am very happy with it. And I can get it at Walmart for $15 for 5qts, so I'm sold. Switching to a semi may be all you need.
 
Hey, whatever creams your twinkie..... not trying to blow smoke up your ass, just giving my personal experience with synthetic oil, like the guy who started the post asked for. Bash the extended drain interval if you want, but I got over my "3000 mile addiction" and have been running Amsoil for over 10 years in trucks that see temps from 110F in the summers to well below freezing in the winters. All run in stop and go traffic in the city and run in dirt and dust in the summers when I am off road a lot. I also tow in the summers. I don't buy new vehicles so the lowest mileage I've started using Amsoil was 50,000. My current truck started at 110,000 and the P5 started at 112,000. The most I ever add is a half quart every six months or so. Synthetic is a lot less volatile than conventional oil. With the exception of the diesel, every engine I put it in drains a little cleaner with each oil change. The diesel just puts a lot of soot in the oil. If I decided to run bypass, I could probably go a few years on a crankcase with regular oil analysis to make sure it was still performing. Just my 2 cents. My dealer has never steered me wrong. Check their website and search for extended drain intervals. They are all dependent on the type of engine, type of oil, and service category. All of my gas engines fell into the 12 month or 25,000 mile (whichever comes first) category with the particular oil I was using. Again, that could be boosted even longer with bypass filtration and oil analysis.
 
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I have almost 103K miles. Only conventional oil has been in it.

I've had a few people tell me that if I switch over now, it will **** up the engine.

Is this true? has anyone else switched over at high mileage w/ a MP5?

Not 100% sure, but I was under the impression that if an engine were leaking oil, synthetic oil would just leak "better". If the engine is burning oil it's not a good to use synthetic either (probably a waste in terms of cost). Sometimes high mileage engines are prone to those problems. I still need to look into that...
 
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Not 100% sure, but I was under the impression that if an engine were leaking oil, synthetic oil would just leak "better". If the engine is burning oil it's not a good to use synthetic either (probably a waste in terms of cost). Sometimes high mileage engines are prone to those problems. I still need to look into that...

Nah, don't think it's leaking oil. I had a compression test done before I bought it. The seal on the valve cover is leaking though, and needs to be replaced. Other than that though, it is not leaking oil.

So, it should be good to switch! =)

I think I'll do it the oil change after next - being that I want to have an oil change with only regular oil - (no lucas added).

Thanks for all the input guys!

(dance)
 
You should also do an engine flush with your last crankcase of regular oil when you switch to synthetic to make sure to get rid of as many deposits as possible. The synthetics usually have better detergent qualities to them so you want to start as clean as possible so that your first crankcase of synthetic doesn't get filled with a bunch of leftover gunk. Amsoil has their own engine flush but you can use any brand as long as it cleans out the gunk. Run it for about 20 mins. at around 2000 rpm and then drain it immediately.
 
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