Oil Change after 30K miles



I haven’t changed the oil in my new KIA for 30K miles, yeah I’ll do it. Should they “flush” the engine to remove any sludge or buidup. The oil was down 2 quarts, so I added 2 more. Yeah I’m an idiot for not changing it regularly, but should I use a synthetic oil?

thanks and my puzzlr answer was better than the one you selected.


Puzzle answer? 30K miles, down 2 quarts? You need to get your priorities straight…Yeah, I know…Duh huh?


You really to consider, and I mean SERIOUSLY consider, dumping this car. It’s days are numbered engine-wise and you’re now trying to close the door after the horses done got out.

And don’t even consider trying to claim this as a warranty issue.


I’ve read comments from good mechanics here that think flushing is just a money maker and may push bad stuff into places you don’t want it. In your case, you might be tempted to think the synthetic oil thing is a reason for trying to set oil change distance records. Maybe go with regular oil/new filter at intervals recommended in your car manual. Look at it this way, for $30.00 you get to have your car go up on a lift and you can walk around and check out other things.

As for dumping the car, you may have lucked out. Time will tell.


No flush. No synthetic oil necessary. Change the oil and especially the filter and drive on.


Do you have any observations that there is material clinging to the insides of your engine that need to be “forced out”? Can you take a look down the oil filler and see black tarry material clinging to the metal parts of your cylinder heads or valve train?

If the only motivation to do a flush is the knowledge that you way extended you oil change interval, I say no flush.


Change the oil and the filter, that’s all. No need for flushing or synthetic.


I would change the oil and filter with a good quality motor oil in the viscosity called for, then do it again in a thousand miles, then 3k thereafter.


No amount of flushing or no amount of oil changes is going to remove the sludge from the engine. If you want to effectively remove sludge from an engine here’s what must be done. http://www.tegger.com/hondafaq/sludge/cleaning_sludge.html



No amount of oil changing or flushing is going to cure damage done by running with the oil capacity at around half for who knows how long (likely until the oil lamp could not be ignored any more) and with aged oil to boot.
This car + how it was treated = near junk.


The future of this car is uncertain; the low oil level, even more than the long oil change interval’ spells bad news.

I would keep driving it and change the oil and filter every 3000 miles without fail.

This is obviously a car most regulars on this forum would avoid buying!



The OP has done me and some other people a favor by reminding us why we don’t buy used cars.
I don’t feel like being the victim of somebody’s failure to maintain a vehicle properly.

As ok4450 corrected stated, this vehicle’s days are numbered as a result of the OP’s incredibly irresponsible behavior.


Well, I won’t write this engine off as my fellow respondents have done. You don’t appear to be reporting any issues of merit. You surely have deposits. I would use Auto-Rx. It can be used in line and all you have to do is change the oil and filter. In your case it may take a few treatments …but …so? You use it in an alternating manner …add drive 2500-3000 miles …change …drive without it 3000 miles …and so one. Works slowly so you don’t dump a mountain mudslide into the sump and pickup screen.


Find the owner’s manual. Yea you got one with the car. It is likely in the glove box. Do all the maintenance that is listed in that book.


I see the doom and gloom responses, yes you need to get on a regular program of oil changes as recommended in the manual, but take it as it comes and check oil level at 500 mile intervals to see how much you are using. That is your starting point.


How does a regular oil change program at this point eliminate metal wear due to:
A. Half the quantity of oil it should have; and likely has only had for a long time.
B. Pitting of cam lobes, lash adjusters, scoring of metal surfaces due to contaminants.

Sludging is only part of the issue and often when sludging occurs one of the first victims is the oil pump pickup screen. Mix in a clogged screen with half the oil it should have and the situation is just made worse.

KBB shows this vehicle in good condition is worth about 12 grandish or so. If someone was offering this vehicle for sale at that price and knowing what you know about the 2 quarts down and never changed would anyone even vaguely consider giving even say 8 grand for this thing?


Do the oil and drive on. Do replacement oil on a real schedule. The damage, if any, is done. Any oil is better than what is in there now. With luck count on getting 60k more miles out of the car.


Why not? Full KBB is warranted as the car has no known defect. You may assume damage if that is your pleasure. There is no proof that this car is in anyway damaged. There is no real reason to assume any damage. We all believe it should or must be so, but you would need a teardown to PROVE it. A new engine has less blow by thus less contamination of the oil by combustion blow. As long as the metal had good lube all is mostly ok.


This is a silly point. You have not even seen the engine. Much less looked at the oil. There is no responsible way to tell this person that the engine has any damage. You just believe it must be so, without PROOF.


Of course it is best to change oil at 3k to 4k but in 2001 I got a new Chev S-10 for a company delivery truck. I drove it around 1000 miles per week. The first oil change was at 25k miles. (it was not my call). The second one was at 48k and the 4th change was at 101k. I never kept track of it after that. I drove it 205k miles before I left the company and it was running fine. I had started using about a quart of oil in atound 3k miles. My point is; The engine was not ruined at 30k miles.