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LS Oil Pan Leak

I have a 2003 Lincoln LS V6 with 41k miles. Bought the car new and have had all the maintenance it has required done. The car has developed a oil pan leak, and from looking at the repair manual pages for this, it seems quite a task to do this. The dealer wants $1300 to do this repair, since it involves removing most of the components from the engine and lifting it, and a local mechanic wants $1000. I have already spent $900 to have all the plugs and coils/wires replaced last week just to get it running again. Should I have this done or simply live with it? I am sure it will only get worse in time, but I am concerned that doing the repair may just lead to other problems, given what is involved in doing it. I would like to keep the car for another 5 years or more if possible, but if this is just the beginning, then would I be wise to sell this car now and move on? If I do the repair, should I have the dealer do it or trust this to a local mechanic of good standing to save a few bucks? Thanks for the advice.

Changing the oil pan on the V8 is trivial, but as you’ve discovered, it is major on the V6.
If the leak is small and you check your oil often, then you might just leave it as is. You might also try tightening the bolts holding the pan on (just a little, not a lot).

The LS is a very nice car, but it is more expensive than most to maintain. I hope that you had the PCV valve, hose, and elbow replaced while the upper half of the manifold was off to replace the plugs. If not, you’ll have that soon. You can also expect to replace most of the plastic parts of the cooling system soon, if you haven’t already.

Good to know. Had a local mechanic do the coil job, and the paperwork does not specify the PCV valve assembly, so I will be prepared for that. By plastic parts on the cooling system, I assume you are referring to the engine cooling and not the AC system? Will be looking for that too. Love to drive the car, but this may be something that will not last as long as my other 2 cars did…13+ years each, with little real expense! Love those old Dodge slant 6 and Mitsubishi 6 engines in my old Dart and Caravan. Maybe it is time to cut my losses.

Roughly, where is this leak at? Anywhere near the oil filter?

The reason I ask is because I’m often skeptical of the diagnosis of an oil pan leak on a late model, low miles car.

It is toward the rear of the engine I believe. When I had the car in for the 40k servicing at the dealer, I asked them to look at it, they said it was the oil pan. When I had the local mechanic do the coils/plugs, he cleaned the area and confirmed it was the oil pan. He was unsure of that at first.

Toward the rear usually means a pan gasket or a rear main seal. Either one leaking would be very unusual on an '03 model car with such low miles on it.

Just offhand, I’d say fix it but that would be conditional on just how sure they are that it’s the pan leaking and not a rear main seal instead. One would hate to spend that kind of money on a pan gasket and still have an oil leak in the same place due to the rear main.
(And replacing the rear main seal means removal of the transmission.)

Just some food for thought but what about the possibility this leak is actually a valve cover leak that is running down and leading someone to think the pan gasket is the problem?
A valve cover leak would be far more common than a pan gasket and some of these can be very hard to determine due to this area not being very visible.

You need to isolate the leak…Is the oil pan damaged from an impact? Is it the oil pan GASKET that is leaking? Or is it the drain plug??

If it’s the gasket, has anyone tried to gently tighten the bolts that secure the pan??

I inspected the engine as best as I could, and here is what I see. It would appear the leak is from the left side of the engine, somewhere below where the dipstick is. None of the components on that side (alternator etc) seem to have oil on them. When I look in from above, you can see oil on the plastic under shield that is on the car. From below, you can see the bottom of the oil pan has a thin oil and dirt coating, and the 2 hoses that run parallel to the engine on the left do as well. On the inside one of these hoses (one closest to the engine) is where I can see the location where the oil beads up and drops off. There is also a spot on the bottom of the oil pan (near the front left corner) that appears to be smooth and oily, not the light dirty oil coating that is on the rest of the pan, and seems like a spot where the oil may bead up and drop off as well. The leak is minor at this point, probably one drip every 20 minutes when the engine is cold. Can’t say what it is like when running or is parked hot. Since I am the only driver, I have not had any impacts with anything so I do not see that as a causation. No attempt to tighten the bolts has been made as far as I know. I would be happy to take some pics if that would be helpful. I may take the car back in to another local mechanic and have them clean the area up and isolate the leak location for me for future reference, and lightly tighten the bolts if it is indeed the oil pan gasket. Even with the low miles on this car, I have already dealt with several issues of varying degrees with it. From as simple a thing as tail light bulbs continuing to fail, to having the coils and plugs fail on me just last month. 3 of the coils failed and the mechanic said several of plugs were failed as well, so I just replaced them all in order to get the car to run again. The Moonroof leaked, ABS sensors have failed, the headlight assemblies are all fogged up (even after being replaced), AC vent covers have disintegrated and been replaced, plus the usual new tires and brakes all around. Fortunately, costs on these problems have been minor or expected once out of warranty until the coils/plugs and this problem. I do not drive the car hard generally, and I have done all the specified maintenance on time. Love to drive the car when it is working, but this oil leak and the potential cost to fix it are really nagging at me.

I have two LSes and I know a few other people with them. My two are great and have been almost no trouble at all. (around 70K and 140K miles) Some of the others have been nothing but trouble. It’s almost like there’s no in between for these. Either you get a good one that will be very little trouble, or a bad one that will be nothing but trouble. Yours sounds like it might be in the latter category.

A leak in the oil pan especially if caused by abrasion does not sound like the kiss of death. I had a station wagon with a gas tank that scraped going up our steep driveway. I could get it to stop for weeks by rubbing bar soap on it. If this is the source of your leak there are gas tank repair items that may work. It is worth a shot if the shiny spot is the source of your leak. Don’t try bondo, I looked at a used car that a guy tried it on and it did not work. Naturally I discovered the patch on my own and asked what he used, I said it ain’t working and moved on down the line. He was a used car dealer that said he would fix the leak, but you gotta know when to go somewhere else.

See if you have a lemon law in your state. I believe you that the car has been well maintained, but it seems as if it suffers one failure after another. You should not have an oil leak so soon, nor should you be having so many other failures. I think by definition your car is a lemon.

The reason I asked in my original post about the leak possibly being near the oil filter is that this could be caused by the oil filter adapter gasket. Leaks from these gaskets are common with age and it’s not that major a deal to change them.

The gasket is a 1/8" thick fiber block with rubber inserts and with age and heat combined with years of being crushed down by the adapter the rubber loses its flexibility and the gasket can leak like a sieve. This can also lead to coolant diluted engine oil.

The one in my old Lincoln Mark was dripping a little and saturating everything in sight. At first glance one would have thought the pan gasket was the culprit there too.
I’ve never done on an an LS but on my Mark it involved removing the LF wheel, the LF inner fender, oil filter, etc. The only real aggravation was getting a hand in there to wrestle those stupid hose clamps. (drain radiator first of course)

On my Mark the gasket was about 13 bucks at the dealer (no parts house had it) and took about 2 hours to do altogether.
For the quote on the pan gasket I would sure consider this adapter gasket first.
This is not the gasket of course, but it does illustrate the adapter itself.

That reminds me of a bud who had oil blow all over the engine compartment of his boat, because as it ended up, one gasket had stuck to the motor, and 2 gaskets on an oif fliter just does not work, for long!

ok a 7 year old car, how many miles? plugs may be normal, coils and wires, not lemon worthy, and we really do not know if it was preventative or needed. I grew up in the 70’s, back then maintenance was a lot more than it is now, but I do not see a winnable lemon complaint here, especially if it was damage to the oil pan causing the leak, my take.