hsmac

does flush like moly do much? my oil hasn't been changed in years so I presume it'd be ideal to do some kind of intensive cleaning. is motor medic at half the price just as good?

fastnoypi

if you haven't changed oil in years, you should use something less aggressive for cleaning. Dislodged sludge can clog filters, ocv valves, passages , etc. I haven't used motor medic but seafoam in the crankcase works well per directions.

Bottom line, attempt to clean over several oil changes.

salimshah

Never shock a machine that is running.

How does the oil look, feel and smell? Check by dip stick and compare with fresh bottle.

Salim

hsmac

i don't know what you mean my shock a machine, could you elaborate?

it looks on the dirtier side -- it's extremely low right now -- but as far as those things go i'm probably not experienced enough to discern if it looks feels or smells properly. it's pretty dark but not black and more oily than sludgy. i don't plan on doing frequent oil changes in the future, unless the consensus is that it's necessary, so if i need to flush several times perhaps i'd do it first using cheaper oil before pouring in my synthetic. i'm also not sure what kind of oil is currently in the vehicle.

fastnoypi

i'm not sure what you can diagnose by look, feel and smell of used oil. Even a tribologist won't be able to discern much on those alone other than its been used.

Modern oils are designed to suspend and trap elements not caught by the oil filter that would otherwise drop out and become sludge. All used oil will have a certain amount of fuel dilution from blowby and turn various colors due to additives..ie detergents, stabilizers, etc..

salimshah

Before we start splitting hairs, hsmac needs to top off oil immediately.

While you research the best oil for your need, grab couple of bottles of Castrol GTX with ratings printed on top of your oil fill cap. You can chose other brands but get a reputable brand.

It seems I over specified for hsmac and under specified for fastnoypi [can't win em all ]

hsmac: compare with fresh oil and note the differences.

For fastoypi, you can send the oil for analysis to a lab.

I am not a proponent of no maintenance. But aggressive massive changes shocks a running system.

Salim

hsmac

ok so i'll be using synthetic after all since the price will be same. after a couple changes should i use a moly or medic?

i wanted to top off the oil last week but thought since i was just going to drain it for a change it would be a waste. if i'm not driving the car, low oil should not be an issue when the car is just sitting there right? how low does oil need to be before damage occurs?

thanks for all your help guys i really appreciate it. can also move this to a new thread if mod feels it necessary.

Australian

I would just change oil regardless of history as because you didn't do it yourself or write date in yourself.
As consider a clean oil swap a flush which will only do car good. Brand of filter and oil that you choose and exact mileage of your service is your peace of mind.

salimshah

I think you missed my suggestion(s). This is what I suggest.

1. Top up the current oil with standard quality oil. [example castrol gtx ..range speed on the filler cap]
2. Use the vehicle to get the engine warmed up and drive for about 1/2 hr.
3. Drain and examine the current oil.
4. Change filter and use regular quality oil for next 3000 miles
5. Drain and examine the oil and then figure out if you need aggressive cleanup or any additives. [Personally I am against both, but if you see any evidence of engine oil gel, you might like to reach for something].

Salim

hsmac

sounds like a good plan. i'm hoping the topped off oil will help do some cleaning before i drain the old oil. when you say standard or regular quality oil are you referring to conventional? i already got some mobil 1 synthetic because it was the same price and thought it does a better job anyway. are you an advocate of conventional?

salimshah

You may spring leaks if you switch to synthetic and there is nothing wrong with regular oil. Baby steps before you make larger strides. I can only suggest, you being the owner should decide what makes sense to you.

Salim

hsmac

well for starters i don't even know if i have regular or synthetic at the moment. i'm just starting to learn about cars so me deciding without gathering info is hard to do. manufacturers say you can switch back and forth between the two no problem -- whether there are actually implications i have no idea. i'm really glad you and fastnoypi told me to stay off engine flush after having not changed my oil in a long long time because many other people say the same thing. manufacturers will tell you the exact opposite sometimes just to take your money even if it means completely damaging your vehicle.

salimshah

Safe means they can coexist.
Synthetics give you longer interval between changes and potentially can work at higher temperatures over time.
3000 miles on regular oil is very safe [provided you buy quality oil and the vehicle is under normal use]. I am only suggesting to defer by 1 oil change interval.

Salim

hsmac

I can do that, but if there's potential for leaking after using synthetic now, won't there still be that potential after one change with regular?

fastnoypi

why not use a synthetic or synthetic blend high mileage oil? You get the benefits of the seal conditioners and reasonably long change intervals.