which oil weight do you use?
 

I have been told by many mechanics to always use the manufacturer recommended oil weight for any vehicle. Old timers on the other hand have always recommended heavy oil as the car ages. I have heard arguments both ways... what are all your thoughts? Will heavier weights cause leaks due to increased pressure? What do you all think about 0 weight oils on the new cars?

Use the oils specially made for high-mileage engines, at the recommended weight. Newer engines need the lower-viscosity oils to circulate and cool properly, which is why most engines now take six quarts, not four.

@HurricaneSSman thanks for your reply and advice... I guess they engineer them to take the lighter weights I just don't like it. My girlfriend's new Honda takes 0w-20 and after her second oil change from the dealer it got real noisy. I thought maybe they didn't put the correct amount back in so I checked the level but it was the correct amount. It was over 90 that day which I would guess thins it out even more. I guess we will all know in about 5 to 10 years if 0w-20 was a good idea or no :) They just keep going lighter and lighter to get better gas mileage (which works). I just can't help to think that such a light weight oil will lack protection. Just my opinion and I am no mechanic or engineer.

Over 200k miles, and procharged. I still use 5w-30 mobil 1.

If you switch to a 0w, keep the 30 still. Don't lower the overall viscosity.

@ChibiBlackSheep 200K wow that is impressive! what type of work have you done in order to maintain the engine and trans? Yeah I would never use a 0 weight I always run 10w-30 conventional different brands but am wondering if I am contributing to my oil leaks or slowing them down. I have the oil pan and timing cover seal leaking slowly. But it ramps up in the summer. I add a quart every 1K or so but hey... always fresh oil!! :)

My car has just under 79K on the clock. I use Kendall 5w 30 synthetic blend. I also treat the engine, fuel system, and transmission with ZMax at every oil change, but that's because it takes me quite a while to accumulate 3,000 miles. I changed it in March and have put a thousand on it since then.... I also tuned out the AFM so that helps as well. I actually get 2mpg better driving around town without it...

I just do my routine maintenance. I'm already on my second transmission. I've also owned and maintained this car since mile 3.

Your leaks are probably just seals and gaskets going. I wouldn't think it's the oil choice at all.

Chifan, what is the AFM you refer to ?

The Active Fuel Management feature that kills four cylinders when cruising. The constant switching from 8CYL mode to 4CYL mode is not healthy for the engine long term. It is much more pleasurable to drive without it. Also, the V8 can sound like a V8 is supposed to sound.............. In the '06 model it was called Displacement On Demand, I believe. I may keep the car for 10 more years or I may sell it tomorrow, but I certainly like it much better now without that crap. :cool:


I paid about $375 for a handheld tuner and deactivated that feature. Other than that, the setup is as it came from the factory.

5w-30 Mobil 1 full synthetic every time.

Both my wife's '11 F-150 and my '13 Malibu take 5w-30. It's nice buying and using one weight of oil for everything.

I try to stick to ACDelco filters on my two GM cars and Motorcraft filters on the wife's truck.