# Do you use synthetic oil?



## Canadian (Dec 14, 2008)

My car is about to have it's 8th birthday. Seeing as it has been so good to me I've decided to treat it well as it reaches old age. I did some research on synthetic oil and people indicated that they liked it a lot better than normal oil. 

I had the guys put in 10W30 Castol Syntec into the car. I drove it for three months and changed the oil like normal. I head that your first run of synthetic should be a short interval because all the "crap" in the engine will get loosened up by the synthetic and drain out. 

I asked the guys in the pit to pay special attention to what color the oil was that came out. They said it was dark brown. It would appear that a lot of "crap" did come out of the engine. 

Now I've put in 5W30 Castrol Syntec and I'm wondering how often I should change it. With normal oil I'd change it every 3 months or 5000 km whichever came first. I've heard I can go 10,000 km on the synthetic. Is this true?

The car is very happy now. Revs smoother, runs slightly cooler, and the idle is flat. At idle the tach used to bump up and down a bit. Now it just sits there dead steady. I just has my emission test done for my new sticker and the car passed with flying colors. In fact the test results were pretty amazing including 0 hydrocarbons at idle. 

So do you use synthetic? Plus how often do you change your oil?


----------



## NaeKid (Oct 17, 2008)

I only use synth-oil on my new engines - less than 50,000km on the odometer. Anything greater than 100,000km and it gets basic dino-oil with a once-a-year oil-change that includes 1 liter of Automatic Transmission Fluid (ATF) added to the oil about 1/2 hr of driving before the oil gets changed (ie: if I am going to change the oil after work, I will put the ATF into the engine just before work, drive to work, home, then do a "hot change")

ATF has alot of detergents in it that will clean out any sludge through-out the engine and allow the engine to run better.

An alternative is to run diesel-engine engine-oil which is the same as gasoline-engine oil - but - with detergents in it.

Now that you have gone to synth - if you sell the car, inform the next owner that the engine has synth in, the type / brand and they will need to use the same stuff as I have "destroyed" engines by not continuing synth-use if it was running it previously (I personally lost two engines due to this issue).


----------



## Canadian (Dec 14, 2008)

What brand do you use?


----------



## dukman (Mar 1, 2009)

I have older cars. I would never use anything but conventional oil as I have not bought into all the hype. Most cars are fine on normal old oil and really don't even need all the additives. Most cars really don't even need the oil changed every 3,000 miles. In fact, many cars could get by just fine on just a filter change and top off with only an annual oil change. But hey, we are a nation of consumers, lets just keep helping those oil companies get richer and richer.


----------



## bunkerbob (Sep 29, 2009)

I only use synthetic oil in my 12KW generator. I have used Shell Rotella multi oil for years now on all of my vehicles, deisel and gas, and include one treatment of Prolong additive, then following up with regular changes, the Prolong booster. I have a 1993 Jeep Cherokee bought in 1994, now with 235,000 miles on it, still running strong. Could be that great 4.0 liter inline 6 cyl. engine though. Never had an enigine fail, yet. Maybe I've been lucky.


----------



## sailaway (Mar 12, 2009)

Unfortunately I have to use what the Jeep Dealer says in order to keep the lifetime warrenty on my vehicle, but after 14 months it has 70,000 miles so in another year I will be collecting from them.


----------



## NaeKid (Oct 17, 2008)

I use Mobil1 full-synthetic in my 2006 Jeep TJ Unlimted. In my 350ci swapped in YJ, I use basic dino-oil. In my little lady's 4.2L powered YJ, it also runs dino-oil. If I was to change to synthetics, I would expect that the uniform shape of the particles would seep through the seals and end up leaking / burning. Dino-oil's particles are not uniform and they seem to bind up better with the oil-seals.

You can find out more about oils and how they work from BobIsTheOilGuy.com


----------



## Canadian (Dec 14, 2008)

Wow all that oil and not one "lube" joke. Good info there. People are way into their oil.


----------



## Jason (Jul 25, 2009)

See, our minds aren't ALWAYS in the gutter...

In my Dakota ('03 with ~85500 miles on the clock) I just use regular NAPA 10W30. My logsplitter, however, calls for 5W30 synth, as does my dad's 2000Jetta turbo diesel.


----------



## szabotage (Aug 8, 2009)

I run conventional oil in my beaters but been running mobil1 on my offroad toy(s) since the rebuild 10 years ago (the motor has been in 4 different vehicles so far). I used to run synthetic gear oils but for the price and frequency of replacing, I opted back to conventional.

anyone try using additives? I used slick 50 back in the 90's and made the car run a whole lot smoother, quieter and cooler. only problem was when I blew rod and wanted to rebuild it, the silicone buildup embedded into the cylinder walls made it not fun to work with


----------



## NaeKid (Oct 17, 2008)

szabotage said:


> anyone try using additives? I used slick 50 back in the 90's and made the car run a whole lot smoother, quieter and cooler. only problem was when I blew rod and wanted to rebuild it, the silicone buildup embedded into the cylinder walls made it not fun to work with


I had an uncle (aunt's husband) who was one of the early dealers of Slick50 when it first came to market. He swore by the stuff - I see it on the store shelves but have never tried it myself. Would you recommend it for my lady's Jeep (I6 w/ about 250,000km). It seems to leak a little bit (1 liter over the entire summer) and doesn't seem to be burning oil (white paper-test after engine has warmed up). I want to keep her Jeep happy for a very long time ... well, at least till we find another Jeep for her! :sssh:


----------



## szabotage (Aug 8, 2009)

I say go for it, if it's a fairly old vehicle and have nothing to lose, I don't think it would hurt.

BTW, do they still sell slick 50?


----------



## Canadian (Dec 14, 2008)

I'm pretty sure I saw some at Canadian Tire last time I was there. I can't say for sure.


----------



## TechAdmin (Oct 1, 2008)

No. My brother is a mechanic and says you only use oil approved for gasoline engines. It has a ribbon on it. Products from same manufacturers will have different Gasoline engine approval product by product.


----------

