98AcuraCLpimp

just askin cuz my buddy did an oil change and didnt remove the filter and added synthetic on top of the old regular oil and hes been bustin my balls to find out if its harmful??
thanks for the help/wisdom

CLdude23

you shouldnt mix the 2. drain it and refill with synthetic ASAP.

liloj

wilp99

flush then drain. and fill with synthetic. not horable for ur engine but will eventually cause dammage

97Acura3.0CL

flush then drain, then add new filter and if you have never ran full synthetic then use a partial synthetic first for about 3 oil changes and then switch to the full it is not recommended to switch from reg to full without doing a medimum grade first to let your engine adapt to the new change

98AcuraCLpimp

thanks for the info...just curious why is that?
so it will fuck the engine if i go directly to a full synthetic?

PDX3.2TL

Makes sense. I did the change cold turkey and didn't have any probs you never know... follow 97's advice...

xrunner86x

The detergents in the synthetic break down a lot of "sludge' built up from fossil based oil. You want to do as 97Acura said and transition over to it so you arent freeing all that build up at once. You probably wouldnt have any problems converting straight over, but its better to do it gradually.

CLdude23

i have switched many cars over to full mobil1 synthetic with no major problems. But one thing that concerns me is that you can develop oil leaks. As said above, the synthetic oil can break down old sludge fairly easily. So think about all the sludge build up inside the gasketed areas....the synthetic oil will go right through it. Happened on the car i just sold when i switched to synthetic. Leaked 3 drops of oil a night from a valve cover gasket.

Anyyways, i dont see the harm in switching cold turkey but it may be better to do it gradually. Either way, syntheic is the shizzle my nizzle

NOMAD

Never had any problems with it.
Read the back of the oil bottle itself. "fully compatible with conventional oils"
There are differing mindsets on "sludge buildup" etc.
I have not seem much proof of this theory in my dealings. But, "it can't hurt" if you are hesitant and unsure.
The BIGGER issue is that you didn't change the filter.
Conventional oils are usually OK for 3-5K (driving condition dependent) Synthetic oils will be good for longer but OIL FILTER ABILITY is the limiting factor.
The filter media is paper, most oil filters use paper top and bottom caps. This paper loses it's efficiency after a while usually 4-5K. The synth oils will last longer than this but most manufacturers specify oil change intervals based on filter ability.
Think of all that lovely new oil being contaminated with your old oil filter breaking down.
Change your filter every time!
Do it today if you've been "cheaping" it by using the old filter. I think the oil is the least of your worries at this point.

Buy K&N, Mobil 1 or Purolator Pure 1 filters at least.

szhosain

Mixing synthetic and regular dino oil is generally not an issue. Sometimes, it actually works a bit better in older engines, since the synthetic may cause a lot of sludge to dislodge and then mess the filter earlier than usual - doing a transition helps! On the other hand, using synthetic regularly is the best way to go (note that this does not necessarily mean that extended oil changes become possible with synthetic oil - the filter is usually the limitation.)

The main thing I would do after switching to synthetic for the first time is do a way earlier than usual oil and filter change (maybe after 1000 or 1500 miles if you have a relatively high-mileage engine ... like over 75,000 miles) to catch the early removal of any sludge in the filter. Then follow with the normal intervals that you want to do.

FWIW, I used to do oil changes at 7500 miles but have decided to drop to 3750 because of the filter size change (it is much smaller now!). I am surprised and irritated that Acura decided to do this change for the older engines too by discontinuing the old filter.

Z

fusionnv

Its a myth. If you ask motor oil companies, they will say u can mix, but it kills the point of synthetic. Kinda like mixing bottle water with tap water. You can still drink it, it just won't benefit u probably.

szhosain

Also, folks, if you want to learn about engine oils, check out www.noria.com. I bought their book "How to Select A Motor Oil And Filter For Your Car Or Truck" by Jim Fitch and it is very interesting and informative reading.

Z

szhosain

Uhh ... partial synthetics are mixtures of synthetic and dino oils.

Z

white99cl2.3

how exactly do you change it gradually?