Just bought for the first time, 5 qt castrol fully synthetic ( fan of castrol oil) for my next change along with my nissan OEM oil filter( get discounts)... Anyway let's hear some feedback

Synthetic or conventional?
Feedback? Concerns? Questions? Comments?

 

There are certain things to consider. How long have you owned your car, how many miles are on the car, and have you always used conventional oil with it?

If the car has high mileage on it, and it's always had conventional oil used, you WILL develop numerous oil leaks by switching over to synthetic. Every oil gasket and seal will start leaking, but not immediately.

I've learned my lesson from this. My previous car was a supercharged Grand Prix. Not knowing if the previous 78,000 miles of the car was regular or synthetic, I started using synthetic. Withing a short amount of time, the valve cover gaskets and then the oil pan started leaking. When the valve cover gaskets started leaking, the oil would get onto the exhaust manifolds and I would smell the oil getting cooked. When I replaced the supercharger with a rebuilt one that was ported with a smaller pulley, I also had the lower intake manifold gaskets replaced and did the valve cover gaskets too.

If you don't mind spending time and money replacing leaking gaskets and seals, then go ahead and switch over to synthetic.

 

I always run synthetic I figure if it's all it's cracked up to be then it's going in my max I use royal purple I changed it after 3 thousand miles and it came out purple
Good stuff I swear by it

 

The car has been on conventional oil all it's 189,000 miles life. I already started a leak at the cam sensor, which I replaced by switching the o ring, and still have one near my rear main seal. I figured since I am dripping a few, and I have been hard it the past few months, I wOuld give it a good change with some fully synthetic.... Also, how about longevity? Would it change my every 3000 mile change to maybe 3500 miles? All Comments welcome.

 

With that much mileage, I wouldn't concern switching over to synthetic oil. It could cause more harm than good beyond developing oil leaks. Synthetic oil can cause sludge particles to loosen up, and if the oil filter doesn't catch it, they can clog up the small oil passages inside the engine which can starve certain areas of oil.

Synthetic doesn't need to be changed every 3,000 miles. The only reason why you change regular oil around that time is not due to it getting "dirty" but rather that conventional oil starts to lose it's viscosity resulting in it breaking down on the molecular level and not being able to provide the proper lubrication to the engine components as the oil starts exceeding 3, 4, 5, and 6 thousand miles. But then again, when the "Three thousand mile" rule came along, that was way back in the day before oil had additives in it to extend it's life and to add lubricity. Modern conventional oil in most cases can be changed around 5 to 7,500 miles, depending on the manufacturer's recommendations, driving conditions and climates, etc.

If you really want to know about your oil change intervals, you can have an oil analysis done after you change your oil, and the lab will tell you how much life was left in your oil after you changed it a your 3,000 mile mark, along with contaminates, fuel, etc. A friend of mine did this and his result is that he can safely double his oil change mileage.

 

I would just like to keep it running as good as it does now since i will probably have to keep this car for at least another year. And with this main seal leak, I am worried that one day I'm not gonna be checking my oil, and develop a rod knock. I was also thinking maybe topping it off a little more than usual, I usually put in a 5 qt Bottle and it's about 1/4 up the dip stick. I was thinking maybe buying a extra quart and maybe putting a little in, or is that too excessive ? And I bring up longevity because whn me and my gf got our oil changes together( her driving a 07 tsx) she asked for synthetic.. She is getting 7500+ miles on one change.

 

I am sticking with conventional oil.

 

If the rear main is leaking, then synthetic will make it leak worse.

After you run the car, let it sit for several minutes on level ground and check the oil level. Don't overfill it past the high mark. The space between the high line and the low line should be one quart, so if it's halfway in the middle, you only need to had a half quart.

 

I'm gonna start filling it up to high mark, just to play it safe for that leak. I really don't feel like taking it apart, unless I was to do a 5 speed swap...

 

Synthetic blend over here.

 

walmart Mobil 1 0W-40 pure one filter

 

Funny, my car had 87k when I bought it in 04. Every single oil change since has been with synthetic. Im up to 136k now with no oil leaks. I doubt the previous owner was running synthetic.

 

Since the OP is a fan of Castrol, Riddle me this:


Castrol makes a great dino oil. So great that they found a way to turn it into synthetic oil. HAHA!

DW

 

Thats always been an old myth, sythentic will not create leaks. Chances are those leaks were already there but were sealed up with gunk and deposits and the detergents in the synthetic oil just freed up the gunk revealing the leak.
Ive switched to synthetic in vehicles that had well over 100k and they were just fine with no type of leaks.

 

Hmm, have about 40 miles on this run... So far, so good lol

 

ehhh i will switch to syn on my next car.

I run pennzoil high mileage 5W-30 every 3k miles

 

Ive been a fan of full synthetic for my 01 Max since it hit 100K without any "serious problems." Fan of Amsoil, but thinking about a Synthetic Blend. Anyone heard or have used that in their rides???

 

I use synthetic in my fast max, conventional in my daily max.

 

I know the grandma I bought my car from didn't use syn oil. I switched it over and no leaks. Lol yea I used to like castrol, mostly the price, until I found out it doesnt start out full synthetic. Legal loophole and they can call it that. Only major brands still using full syn are mobil 1 and AMSoil

 

Agreed...

 

Not true. By definition, synthetic is more refined, thus thinner. If you compare a 15w30 Conventional vs. 15w30 synthetic the visual is imperative and noticeable to the naked eye in the color.

Synthetic also runs hotter, and may break apart clumps that, true, might have been there in the first place, but with time, the clumps isn't what breaks apart and cause the leaks. It's that the oil is so thin that it can squeeze through the clumps and come out as a leak.

I personally tried synthetic for, I kid you not, less than 3 weeks, because it just made my bay stupid hot, and it started leaking more so than it was in the first place, from the rear valve cover and camshaft seal.

Since then, I've never gone back to it. I always use conventional 15w30 with Lucas Oil Stabilizer to increase the viscosity and life of my oil.

Just my .02 OP

 

Same here brothas!
I've used the syn-blends before. Valvoline, to be exact, the high mileage one. I liked it for what it was worth and didn't cause any leaks or heat issues. It did make everything nice and smooth though throughout the ride (NO HOMO!)

 

Every time Im around an engine builder I always pick their brain. Never have I heard one say they use conventional in a higher milage import engine. Its not like its much more expensive and why risk breakdown for $5 or $10 xtra is my point. Theres so many benefits and so few drawbacks, myths of instant leaks dont count

 

Post hoc ergo propter hoc

 

Both my I30 and Max have over 220k Miles. Both get Full synthetic Royal purple 5w30 with Royal Purple filters every 5k miles. I've considered trying AMSOIL on my next change. Haven't decided yet.

Synthetic is supposed to lubricate a lot better vs Conventional. Better cold starts, better heat transfer, etc etc. I'm sure many will argue but there is some proof out there. You'll never see race cars using conventional, just sayin. It also doesn't have to be changed as often. Supposedly AMSOIL full synthetic doesn't have to be changed for 15k Miles vs 3k for the standard conventional.

 

yea but from what i understand, you shouldnt jus make the switch to synthetic. U should do an oil change to a blend, run that for a month wit a new filter. After the month is up, do an oil change with syn with a new filter. now u good to run syn

 

Funny...that's exactly how we change dog food brands for our two dogs. We run them on a half an half blend of the new and the old for a couple weeks, but no filter, then change over to the new brand full time. Otherwise, they tend to leak out the back end....

 

 

Synthetic > Conventional.
All myths about switching are garbage.

bulk of problems are from incorrect VISCOSITY change, not actual oil blend type.


/Thread

 

From what Ive read on this forum. It seems the 0w-30 castrol German is the best oil for the VQ motor. Though ive also read the b.c is so thin it will leak through worn gaskets...

 

as did I. Had high milage switched to synthetic and now I was leaking and was low on oil and caused some knocking stuff. Im goim back to high milage this week

 

how many threads do we need on this subject??? it is not a myth that synthetic will cause problems with a high mileage car, its made more for racing and lower mileage engines cause its thinner than regular oil. plus, the $hit is expensive and does'nt make any difference in a high mileage car, period.

 

Mobil 1 0w-40 because RaceCar.

 

hi there, i agree. i bought my maxima in2006 and changed to syn.and next change was almost 1/2 quart low so went back to castrol and it uses no oil between changes 10w/40 with 142,000 miles and it screams,best car i,ve ever driven considering it,s a 6cyl engine.

 

The truth is, unless you plan to keep your car and gauge its performance up to at least 100K, don't bother with it. Really, people want to feel good when they believe oil will be the cure all. The FACT of the MATTER IS, when cars are 10 plus years old w/ 150K on its speedometer, seals are bad, leaks are occurring, and most of all, parts are just aging.

While oil and a good filter are critical, it is not going to do anything in terms of fixing your problems. Given today's technology, as long you change your oil and filter periodically, you are fine!

I use puralator oil filters and mobil 1 on my newer car and plan on keeping it for a very long time, unless it starts giving me serious issues.

With older cars at the 100K mark, I've stuck w/ 5w-30 Valvoline or Castrol brand. No serious issues, or concerns from me.

 

Not sure if serious, but you have a point I guess. Same w/ cooking oil. Some oil is made for cooking, some not. hahaha

 

Is for real? Can to not tell.

If you're serious, you're wrong.

either way this is an argument that people seem to make their own opinions of for whatever reason. Simple fact is, synthetic is better, period.

 

exactly right Syn is better for high mileage engines thats the only FACT I know of. Read up on this http://www.upmpg.com/tech_articles/motoroil_viscosity/ and this as well http://www.upmpg.com/tech_articles/m...son/index.html. Obv AMS wins in their "independent test" but the other results they have no reason to lie and are probably pretty damn accurate.

 

iv read some funny post on here... This is by far the funniest

 

He just wanted some attention, he a mr know it all lol