I know exactly about this. I used to work summer jobs at a couple of dealership service dept. as a shag boy in high school. The mechanics would bemoan the warranty work and call the non warranty work “gravy”. They would go up to the service writer and either ask for more “gravy” or complain they weren’t getting enough gravy. One thing I will say, they tended to do better work on the “gravy” repairs than on the warranty repairs.
Dealer service said synthetic oil will cause my 2003 Subaru to leak.
- Thread starter lokijoker
- Start date
Iyt was true 40+ years ago when "True" synthetic caused gaskets go leak. No more. It now has additives that prevent it.
Nice job man. Stay away from dealers, sham extortion rings is all they are. To make your change even easier, throw a fumoto valve on that beast!
I did get an extractor which works well with my other 2 cars since the filters are reachable from the top of the engine. I used it to extract the oil from the Subaru but you still have to go under for the filter (which my neighbor did for me.) While he was under there we decided for him to pull the plug to see how much oil was left after extracting it and about half a quart drained out. So not perfect but maybe I need to move the extractor hose around a little more.
For a boxer engine, he is correct.
Regardless of which oil is used, they leak.
Based on what? I've owned Subaru's for 27 years, please explain.
I wound up doing the oil change myself with Pennzoil Platinum High Milage and so far no leaks.
I wound up doing the oil change myself with Pennzoil Platinum High Milage and so far no leaks
Yeah, between me and my Dad, we’ve owned over
Yeah, between me and my Dad, we’ve owned over 10 Subarus is the last 30 years, most of them used, and never had one ever leak.
The dealer wants you to buy a new car.
Yep!
Funny story: My Dad found this 03 Subaru in 2010 with only 10k miles at a Honda Dealer. We went to this Subaru dealer to buy some accessory and the service manager saw the Honda dealer license bracket and asked my Dad if that was the Legacy Wagon with 10k miles on it? (They must have seen it listed on AutoTrader.) When my Dad said, “Yes”, he gave him a punch card with several free oil changes on it. He did this to obviously try to sell my Dad additional service and “find” things wrong with it. Every time my Dad and then I brought it in for those free oil changes, they always “found” some very serious problem that needed a repair. Each and every time it was BS.
Carlostrece
$100 Site Donor 2025
The dealership might be right. This happens with a lot of old cars when they're switched to synthetic. It happened to my old 97 Buick Park Ave, but those are already prone to leaks. It did not happen to either of my old Jeep Cherokees, a 96 & 99, but those are less prone to leaks. However, the old Cherokees did experience lower oil pressure with 5w30 and 10w30 full syn, which was not an issue with conventional 5w30 or 10w30. I then tried 5w40 full syn in the Cherokees and then oil pressure was back to normal.
The safest course of action is to continue using the same oil your dad used. You know ot works. Why spend extra money to roll the dice on full synthetic? Your car doesn't need full synthetic.
Every mechanic who I personally know recommends against switching an old car to full synthetic, or at least advises customer of the risk. Why risk it?
Think of it as a bet.
If you win the bet, you get to spend extra money on expensive oil that you don't need. That extra expense will be ongoing and synthetic won't be on sale most times.
If you lose the bet, you have an oil leak or low oil pressure. Maybe both.
The bet is all risk, no reward. I suggest listen to the dealership on this issue.
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Sure, it could probably live a long life on conventional oil, however, with miles that low and the cost difference between conventional and synthetic practically nothing, why not? Really comes down to how long OP wants to keep it and if he wants to keep it tip-top.
Carlostrece
$100 Site Donor 2025
It also comes down to possible oil leaks that might result, and other potential issues I mentioned. An older car (in years or miles) might start leaking after changing to synthetic oil. Personally, I see no reason to risk it. I can understand why the dealer doesn't want to risk it. Why should the dealer take a chance on potential future hassles over potential leaks? Especially on a discounted oil change they're probably not making any profit on.
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Carlostrece
$100 Site Donor 2025
It doesn't always happen. I was very clear about that. But it sometimes happens. Why should this Subaru dealer take a chance on possibly creating a leak problem? The dealer doesn't need those risks and hassles, especially not on a discounted oil change that they're probably not making any money on.
I switched 2 old Jeeps to synthetic with no problems. I switched 1 old Buick Park Ave and it now leaks. I have a ⅔ batting average switching old vehicles to synthetic. That's pretty good. But my favorite vehicle now leaks with synthetic, even though it's a high mileage synthetic.
You switched 1 car successfully? Good for you. That doesn't tell us how it'd work out for the OP's Subaru. We don't know if his would leak. The dealership doesn't know either and they wisely don't want to risk it.
Lastly, there's no reason to switch his old car to synthetic. It's been doing fine on whatever oil it's been using. If it aint broke don't fix it.
There are multiple reasons to use a synthetic oil. Oxidation resistance, better resistance to deposit formation and reduced ring sticking and coking are just a few. These are benefits independent of the vehicle brand despite dire warnings to the contrary. Synthetic base stocks also tend to require less VM and have better cold-weather performance.
Chance of leaking is just a trivial issue, imo. If it’s of concern put a HM synthetic for a little extra in the way of seal conditioners. No way OP’s car won’t benefit from synthetic.
Carlostrece
$100 Site Donor 2025
None of those are compelling reasons to switch an old car that's doing fine on conv or blend. If it aint broke don't fix it.
I'm not going to debate this further. Do as you please. OP do as you please as well.
And likewise your seemingly unique experience isn’t compelling either, right? Old cars are poster children for the things I listed.
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