mbsigman

Howdy all. I did a search on this on the tech forum and added a post to a very old thread, but the thread didn't show my posting so I thought I'd post here.

Had my '07 in for its first alignment (which was still within limits and needing only minor adjustments ) and noticed some oil on the pan. I've never seen drop one of oil on the garage floor, and the oil level on the dipstick hardly ever moves. I think I've added perhaps a quarter of a quart between oil changes since I've owned the car.

Some have suggested that this may be something called "oil pan sweat" as opposed to a full blown "oil pan leak". Can someone out there make me smart as to what exactly "oil pan sweat" is and why it's normal?

I'd really like to avoid having to replace the oil pan gasket if possible, even though the car is covered under the extended warrantee.

Thanks

Mike

LS WON

thirtythird

I've seen this on the front corner of my pan. When I traced it, it appeared to be coming out of a pan bolt near a couple of pipes. I cleaned it up and ever so slightly tightened the bolt and will see what it looks like next oil change. No big deal on my 07.

REVAK

I think it is related to the porosity of the aluminum itself.

mksz51

My 2005 (which admittedly has only 16,000 miles) is dry - everywhere. My point is it's been around now for 5 years with oil in the pan. If the pan was "porous" it should show by now. The pan isn't porous - if it was everyone would have the problem and the entire pan should be affected. If you see oil on the pan you have a leak. Period.

Red Rochester

SRQStingray

Absolutely. Aluminum is not that porous.

haljensen

It most certainly can be. Alloy, casting technique and handling can cause it to be porous.

The '05 service Manual even admitted that some OEM cast wheels were porous and gave step by step instructions on how the dealer was to handlethem.

cthusker

... I've personally seen more than one pan with "oil stain" on the outside and it was definitely not leaking from seals. All depends on the casting and grade of aluminum used..... So yes you can get "oil sweat" or staining and have your seals be in perfect condition....

MARSC6

I never heard of oil pan sweat. Any oil is probably seeping by a seal or if its just a stain I would bet it happened during an oil change.

quickc6

Had my Z in at the dealer for this same problem . Was told it was leak checked with a dye and driven 18 miles . Was " told it was not leaking it was weeping " .GM well not fix it Not happy about it , but not much I can do about it . Seems to be a common problem .

The NNIAL8R

....What you have is a seep....However, you can put a teaspoon of oil on a hot surface and it's gonna look like a quart has leaked out, especially after dust has stuck to it......If it's not accumulating on your garage floor I wouldnt "sweat" it....If anything, get under the car (the best you can) with the wand at your local car wash and give it a good bath...

GSRANDY

A leaker is a leaker.............

The presence of oil on the outside of your oil pan is an issue that should be addressed under warranty whether it's dripping on the floor or not if you so choose to have it repaired.

Regards,

GSRANDY

The NNIAL8R

Ever look under the hood of a vehicle whose owner never cleans the engine???....After a while the oil seepage film (common in most engines) gets blown all under the hood from the cooling fan and the mere act of driving down the road.....dust sticks to it...It's looks like a HUGE leaker...when in reality the owner never has to add oil between changes and it never accumulates on the garage floor....Engines need to be periodically cleaned the same way the rest of a vehicle needs to be cleaned...Ive seen many beautiful Vettes over the years...that is until the owner lifts the hood

mannyg

Just came across this post after doing a search because my '07 also has slight oil pan leak. Took the car to a dealer in 2009 and they put dye in the system. I took it back after driving it for 3,000 mi and they told me they couldn't find the leak (miraculously it stopped leaking). Damn thing still leaked. I took the car to a different dealership last week and they found the leak no problem. This tells me the first dealership just didn't feel like fixing it or that the leak got worse, meaning it probably gets worse the longer you wait so get it into the dealership (before you tune the engine). I found out this voids the 5 year powertrain warranty. Luckily I had documentation that the leak was there before I tuned the engine (when I took it to the first dealership) and they took care of me. Probably a little off the subject but if you think you have a leak (or "sweat") get it fixed, it's a leak.

Mad*Max

I have an 07 and for the last year or so I noticed oil on the pan but now it is leaking on the floor. As soon as my insurance goes back on Mar.1st I'm gonna take it in to get fixed.

So to the OP, I would say it is a leak and will only get worse, eventually.

laconiajack

Older engines with cork valve cover gaskets, road draft tubes, and leaking crankshaft seals used to be covered in oil. Highways used to have oil streaks down the center of every lane due to this leakage. Modern engines shouldn't leak at all. My LS3 with 20,500 miles shows zero oil film underhood, zero oil seepage or leakage around the oil pan or any other part of the drive train, and consumes virtually zero oil from engine operation. You also should loose zero engine coolant. One oil spot or coolant drop on the floor of your garage means you have highly excessive leakage (not to be confused with aircondtioning humidity condensation). A weeping oil pan is a defective oil pan and should be replaced under warranty.

AORoads

that's what a Corv. racer said to me, and that's what the dealer tech concluded. result: replaced oil pan.

Greenstealth

I just noticed this occuring on my z. The bolts actually appear to be the place I'm "weeping" at. I'm going to try some o rings or rtv or something. These threads seem to be popping up more and more.

Mad*Max

do they replace the pan or reseal it with a new gasket?