I have nothing to do all weekend, so I'm changing my oil. My car has 191000 on it, so I was considering synthetic. Do I just use the regular 5W30?

 

Synthetic /may/ be a bad move on a motor with that many miles on it. Synthetic molecules are smaller than dino-juice, and the oil can sneak out of places that regular oil can't- such as, your old engine seals. I used to know a girl in Canada with an '83 who tried synthetic and she got a TON of oil leaking out from everywhere.

Of course, there was no harm done, she just went back to regular oil and the leaks stopped- but she wasted all that $$ on the synthetic.

But motor age/wear aside, yes, just use whichever viscosity you were using before.

 

I've used Mobil1 Synthetic, Valvoline MaxLife (which is not a synthetic), and now I am using RedLine which is a synthetic oil. I have not noticed a difference in oil leakage at all and my motor has 197k on it. I keep track of how much oil I add between changes as well and have noticed no large difference. I will say to stay away from higher mileage oils. These oil companies put all sort of seal conditioners in there that supposedly expand bad seals. That's a great idea but in my two cents it seems like that can also accelerate the poor condition of the seals as well. Just change your oil every 3k miles or 3 months and you will be fine. If synthetic is too expensive try a blend which almost all manufacturers have.

 

Well, I just grabbed some regular Quaker State 10W 30. It's all we use in the household, so I don't buy nothing else. But I also grabbed some No smoke/Stop Leak, which has worked before, on a 1993 Safari van with over 250,000km on it.. Hopefully I can stop this thing from leaking, because it's leaving a pretty nice stain on my garage floor...

 

? kevman? you have a leak ?, where is it coming fome exsactly?,

 

From the front of the oil pan. It's black, and is the same colour as the oil on the dipstick, so I know it's from the motor. It could be the drain plug, aswell, but probably a worn gasket.. Hopefully not a front seal..

 

Mine leaks a little bit of tranny fluid. By the time it reaches the floor it has picked up enough dirt to look just like engine oil.

 

neo oil, royal purple...............all i use. expensive but great

 

Well, It could be Steering fluid too, which would be a pain to fix, as the seal is right on the bottom of the steering box. But I'll fix what I can, and hopefully it's not something too crazy.. Like a crack in my casting..

 

Take your car to one of those "coin-op" car washes and spray everything with some de-greaser. Makes it easier to find leaks when everthing is nice and clean.

 

I now run Mobile 1 Full Synthtic. I ran Castrol Syntec beforehand. Mobile 1 is supposed to be good stuff, all new GM motors come with it off the line as well, I dont know about all, but the GTO's and Vettes do. If you really wanna use good stuff, pay more and get Royal Purple. I hear its good, I havent used it though.

 

If i were you i would use Royal Purple 15w40. Its alittle thicker and will stick to the walls better. Just all around better for your engine but if you use royal purple then you have to keep buying royal purple. you cant use any other oil after that because it will possibly ruin your engine. Its got a certain chemical in it that does that.

My buddy used that for his 92 and it worked great. It feels alot more powerful. I need to do that to my car to because my milage is up there as well and its well over due for an oil change. thanks for reminding me by the way.

 

Hey guys, what weight oil do you think is good for the Texas (Gulf Coast) Area, 137k miles???????? 305 TBI, Thanks, Tom