Hey guys, I have a 2000 Chevy Venture. I stupidly had a repair shop change my oil because it was 5 dollars. They put in 10w-30 and I didn't realize it until after I drove it for a bit. I now sem to have an oil leak out of the filter, drain plug, and oil pan (small leaks). I usually put 5w-30 like recommended. Could the 10w-30 oil be to thin and perhaps that is why I all of a sudden have leaks. I live up in the Northeast and our temps dropped into the teens this week but I think it was doing this before it dropped. It had been in the 30-50's before this. I appreciate any input.

There should not be any leaks no matter what type of oil is used. I would have to say that your mechanic felt you did not pay him enough to tighten the drain plug and oil filter!I would get under the car(yes I know how cold it is) and tighten those items up. Clean up any oil that previously leaked. Drive it around for a bit. Park and put a piece of cardboard under the engine while it sits there overnight and in the morning check it out and see if its still leaking. If it is then determine where the leak is coming from. If it turns out to be your oil pan gasket then consider the mechanic innocent and thank him for putting in thinner oil thus alerting you to this future(very near future)problem. Good luck

Make sure the guy did not add too much oil.

Actually, I did forget to mention I made sure everything was tight. I was out there yesterday in the 10 degree weather. It was cold but had to do it. What I found was oil seems to be dripping from above and down onto the transmission oil pan. I looked quickly and thought it was the oil pan (duh!). I cheked the valve cover and that seems fine. I am not sure what else might be leaking. I can't pinpoint where this is coming from but if you have any ideas let me know. This vehicle for being a 2000 is a piece of junk. We always have problems every year but can't afford another vehicle.

Needless, to say I won't be using them for anythig in the future and will continue to do my own oil.

Thanks for the input.

TX, I just saw your post. Where would it leak from if they added too much oil. That might be a possibility. Thanks.

If its not the oil pan and its not the valve cover then another UNFORTUNATE possibility is the rear main oil seal is leaking.. and if that is the case then drain the oil and put in thicker oil because that's not something youde want to change unless you absolutely have to!if the leak stops after you changed the oil then that's great but keep an eye on it and check for leaks frequently. This post has nothing to do with the overfilled question you asked txgreasemonkey . I'm also watching for his answer on that

The engine would try to force it out anyway it could. 10W-30 is heavier than 5W-30 and, in the cold, it could be causing too much oil pressure; hence, the leak. This is just a possibility, however. You need to see if this makes sense in your situation. In my opinion, you should run synthetic 5W-30 year-round.

Oh OK. I didn't realize the higher the number the thicker it is. Will it damage my engine or just leak for awhile?

I will check travman514's idea of the rear main seal once I find out where it is. These engines compartments are so compact it is hard to see.


After thinking about it, since it is leaking from a few different areas maybe it is there is too much oil. I gues the question would be if it would damage my engine and if I should drain some out.
Thanks again guys.

Personally, I would drain the 10W-30 out and replace it with 5W-30. Winter is not even here yet and your problems could just be beginning. Some cars are quite sensitive to the viscosity or the oil, while others are not. Newer cars tend to be more sensitive and not like heavier oils.

I will do that then go from there. Thanks for your help.

Let me know if this solves the problem.

I changed the oil and it is still leaking. I do have someone now I can talk to who is a service manager at a Chevy dealer. He tends to think it might be that they overfilled it or spilled some and it is still leaking down. Without looking he can't give me exacts. I wiped down the areas and will check it out tomorrow. I will be able to have him check it out if it still leaks so at least I have a way to check it without it costing me an arm and leg. Thanks for your help guys.