Did Syn Cause Oil Leak in '04 Pilot?

[Thorn]

About nine months ago, I bought a used one-owner 2004 Honda Pilot (3.5L) with 7,400 miles on it. It is a Honda Certified Pre-owned, so it had a fresh oil change when I bought it from the dealer who had sold it originally to a local lady who traded it back for an '05 Accord (Pilot was too big). At about 10K miles, I changed the oil with Havoline 5W-20 dino. At 13K, I changed the oil with Amsoil S2K 0W-30. The engine was perfect at this point.

Today, at 18K miles, I dumped the S2K and replaced with German Castrol 0W-30. While under the vehicle, I noticed fresh oil on the oil pan near the drain plug, and I thought the plug was leaking (always use new crush washers). However, upon further inspection, I noticed that there appears to be seapage coming from the oil pan gasket (caulk-like material), oozing down and wetting the oil pan bottom near the plug.

Looking around on the Internet, there's a guy over at HondaPilot.org that developed all sorts of leaks on a Pilot (rear main, cam seals, oil pan, etc.) immediately after switching to synthetic. He is having all of this repaired, supposedly under warranty, but I wonder if the engine will ever be the same.

Anyone hear of similar stories with the Honda 3.5L engine and synthetic? Should I dump the GC immediately, switch back to dino, and hope for the best? Should I replace with 5W-20 and take it in to the dealer under warranty?

I am really getting concerned about this. Any advice would be greatly appreciated.

 

[ekpolk]

I seriously doubt the syn had anything to do with the leak. How 'bout one of those occasional bad seals that gets through. I've used synthetics for two decades and not ever had one leak like that. I've put them into domestic and foreign cars alike, and no leaks. Actually I had an 88 Civic that leaked once, but that was from overtorqued, cracked drain plug threads, not the oil. Keep looking, and good luck with it.

 

[Ken42]

More of a chance of the oil pan hitting something and breaking the seal then the oil causing a leak......

Ken

 

[97tbird]

Cars which run dino oild often get leaky with syn.oil, when switched to it, sometimes because the "false" seals are washed/cleaned off by the syn.
How come its always some other mechanical coincindence, exactly when switched to syn? I have personal experience with ,my car, which went thru the same thing...took a bunch of experimenting to normalize oil consumption to zero, and a lot of time...even after switching to dino.

I's go back to dino and play it safe.
and GC is not a magical oil which performs great in ALL kind of engines.

 

[Pablo]

If the car leaks oil at that low of miles, it's defective. Have Honda honor the waranty.

 

[Bryanccfshr]

If I understand the description correctly This is an oil pan gasket leak?? Not even a friction seal.
18k miles aint long enough to get a false seal in a modern vehicle.. this is a defective gasket or factory torque is not correct on the pan. Take it to the dealer and point at the leak, get it fixed and run whatever oil you like.

 

[merlin64]

I agree, this is a factory defective seal or assembly error. This engine is the same as the 3.5 in Honda Odyessys and nearly identical to the 3.2 and 3.0 in Acura Tl's and Accord V6's, respectively. If syn caused leaks in these engines we would know it by now, tons of people using syn on the Ody, TL, and Accord V6 boards.

I would take it in and say "hey, this thing is leaking" and let them deal with it.

 

[Jim 5]

My wife's TL has been running Mobil 1 0w-20 for the last 30k miles, and the oil pan and rest of the engine are as dry as a bone.

I suspect something else is causing your problem.

 

[tenderloin]

Yep, even Honda makes a mistake

 

[benjamming]

Thorn,

Have you double checked to make sure that the oil pan bolts are torqued correctly?

97tbird,

On engines with higher miles, you raise a valid point. However, with < 20k miles, this would not be the case IMHO.

 

[Thorn]

I'm not the mechanical type, and I don't have a torque wrench. However, I did put a ratchet and socket on all of the bolts just to be sure that none of them were loose. I applied a moderate amount of pressure, and none of them turned, so at least they are somewhat tight. There was one bolt up under some type of frame cross-member, so I couldn't reach it, and it was in the area of where the seepage is occuring (it appears to be leaking only in one corner of the oil pan).

I wiped up the oil as best I could (it's not a whole lot). I think if it keeps leaking, I will take it in to the dealer for a warranty repair.

 

[Rickey]

Thorn don't mess around with it take it back for warranty service. The synthetic oil didn't cause your oil leak. This is a manufacturing defect, barring impact damage of course. I have accumulated over 475,00 miles on four vehicles allmost all milage clocked with synthetic oil in the crankcases,with no measurable leaks. My '93 Cavalier has over 234,000 miles with only a slightest trace of dampness on the rear of the oil pan, and that is the worst of the bunch. Your Honda should beat this. Good luck. Rickey.

 

[pscholte]

Ken42 is right...I think it was the iceberg...

 

[Michael Polutta]

I have a 2003 Odyssey w/ the same engine. Other than the factory fill it has ALWAYS had synthetic, and does not leak.

So, nope, not the oil's fault.

 

[Bill in Utah]

My Dads 2001 Civic got a leak around 15k and they replaced the oil filter first.

Still leaked.

The pan gasket second.

Still leaked.

Valve cover gasket third.

Still leaked.

After 3 trys, he bumped it to a Field manager who said take it to another Honda Dealer (the first one was 25 miles away..2nd is 50 miles away) and they put in dye and said drive it for a week and come back.

Still leaked.

Went back and they said there was too much dye on the engine so they steam cleaned it. They put in more dye and said drive it for 60 miles and come back.

He did and what was the problem?

Hole in block.

So, they had the outfit for 2 weeks and replaced the long block. The 2nd Honda dealer said they replace 25-30 long blocks every year for poor blocks. Either the 1.7 I4 or the 3.0 V-6 he said were the problem blocks.

He drove it with the new engine and all was great till he sold it last year. The new owner has had no problems with it and it just turned 100k.

Hopefully the bad blocks are not in the 3.5 v6... My Dads new Vue has the same engine. (so far no problems)

If you take it to the dealer. Make sure they steam clean the block and put dye so they KNOW what is leaking. The Dealer wasted alot of my Dads time "fixing" the leak...

Take care, bill

PS: Honda did cover my Dads rent a car each time they had his car and did extend the Powertrain warrenty to 70k miles no time limit for him.

 

[BobXRC]

Since its under warranty, let Honda figure it out....BUT, you might want to take a look at TSBs first (or at least make sure they do). I remember reading about this engine in the Honda Ody - it was a TSB about engine leaks. The alumin block can have pores that are big enough to weep oil in rare cases (first time I've ever heard of such a thing). The fix was putting epoxy glue over the area.

This might not be your problem, but I've always found that if you go into a dealer and let them know that you've been investigating the TSBs they tend to do a better job at researching the problem. P.S. Honda trys to hide the TSBs from the general public - try looking around the web (ody club, acura etc, your engine is in a number of Honda/Acura products)

 

[BobXRC]

I went and back tracked what I read.
Its Honda TSB 01-009 august 21, 2001.

It shows a bunch of different places that could be leaking. I think I counted six different places that leaks can occur from (abnormal). And yes, it had one repair that involved using JB Weld ....wow!

Anyway, don't let your dealer tell you that the engines can't leak.

 

[ekpolk]

The porosity of aluminum is often a source of problems. My 17 year old son received a gem of a gift from my mother-in-law: her 87 Cadillac Seville that has only 57,000 miles on it (no typo). This is a time warp car that's spent most of its life in a garage. It has the oddball 4.1L V-8. It's from the relatively short-lived family of aluminum block, iron head (that's right, notbackwards) pushrod V-8s. This engine is notorious for coolant leaking through the pores in the aluminum block. GM cooling system veggie tabs are the prescribed remedy. Apparently, casting Al is a tricky art and significant pores are hard to avoid. Interesting to hear that even Honda can't avoid the problem. BTW, don't try the GM veggie tabs in your crankcase. . .

 

[Bob A.]

Off/on topic(s): Anyone have similar antifreeze leakage problems with the Subaru 2.5 liter aluminum 4 cylinder engines? Last summer I had a head gasket replaced on my '02 Legacy Outback under warranty to correct an antifreeze leak (make that gush). I was told by the Subaru maintenance department that the 2.5l aluminum block tends to expand and contract more than an iron block, and head gaskets in this configuration tend to break their seal(s) and leak under these circumstances, creating antifreeze contamination. They said that, besides the head gasket replacement, the long term fix was a chemical additive for the antifreeze, much like that which is added to diesel engine radiators to eliminate cavitation.(?????). . . although in the case of the Subaru engines, the additive is to eliminate the breakdown of the head gasket seal.

My last UOA showed a small amount of potassium. Based on what has been said here, I wonder if the block has some leakage due to aluminum porosity? Any thoughts? -- or information about related experiences with engine antifreeze leaks in Subaru 2.5 liter aluminum engines? If this is off-topic, point me in the right direction of where this question should be raised. Thanks.

 

[Bob A.]

I forgot to mention that the head gasket leak came toward the end of a 3000 mile OCI for Royal Purple synthetic 5W-30 -- the only synthetic oil used in this '02 Outback during its 54,000 miles of operation.