I have been noticing oil spots on my garage floor where my 03 QX4 is parked. I had the valve cover gaskets replaced and that stopped one area of leaking. But I still have another in the area of the oil pan. At first I thought it was leaking from the lower metal oil pan through the RTV silicone that seals that pan to the upper aluminum pan. But now I see that it is likely coming from where the upper pan bolts to the transmission (see pic from Ser. Manual & my pic of the leak itself.) I hope this is the correct description. There does not appear to be a gasket there. Any advice as to how to stop this leak? It looks like an expensive job if I have a shop do it.

Well, I tried to post pics but can't figure out how. I have them and will give it another shot if someone will kindly tell me how to do it. Thanks.

Upload pictures to www.imgur.com.

I had my rear main seal and upper & lower oil pan gaskets replaced by a local AAMCO for approximately $1700 total, if I recall correctly. It is indeed a very expensive and laborious job to do.

Ensure your valve cover screws are tightened. I know you just had the valve cover gaskets done, but it doesn't hurt to check. If they aren't, oil can seep from the rear of the engine and mimic a rear main seal or oil pan gasket leak.

Thanks. I uploaded 2 pics to that site. Hope you can see them. On the pic I took, you can see a bit of brown oil forming at the seam. I think that is the source. Do you think a valve cover leak could instead be the source; that is, that the leak is trickling down to that area?

You need to link to the images here. I think imgur should have given you options for copy & pasting links to the images on forums.

Let's try this:

http://i.imgur.com/wTggO.jpg

http://i.imgur.com/wTggO.jpg

Does this look like your leak?

Yes, I haven't seen that much at any given time but that's it.

That particular leak was from my vehicle. My rear main seal and upper oil pan gasket were leaking.

You should thoroughly degrease the area and place a piece of cardboard under your parking spot and try to trace where the leak is emanating from.

Yes, I have done that. The drops on the cardboard appear to directly be below the area in your picture. Some oil probably glances off the lower oil pan edge; that's why I thought initially that the leak was seeping through the RTV silicone there. Did you have this problem fixed? If so, do you recall what you paid? Thanks.

Your rear main seal is leaking. It's a very labor intensive job to replace it, and it cost me I think around $1300 to have replaced at an AAMCO.

Ugh. But thanks so much for sticking with me on this. I will take it to a reliable shop tomorrow & report back if I learn anything useful.

Yup, rear main seal it is. Independent trusted shop has quoted me around $600. However, I'm going to try about a 60 cents fix first. While investigating the leak issue, I had occasion to call tech support at Permatex. The rep told me about Spray Sealant Leak Repair that, in his opinion, will stop the leak. I believe it is a fairly new offering and is designed to block those small leaks that drive us all nuts but are beyond the scope of most DIY'ers and cost a bundle to fix at a shop. It forms a rubber barrier that I have examined by spraying on some scrap metal. It does indeed dry to a firm but somewhat flexible finish (dries quickly, too). Anyway, I am going to give it a go around the area, TownCivilian, that you featured on your picture. I will clean it first with acetone & then spray 2 or 3 coats. My leak is so slow that I think I can get the spray on & dry before a new droplet forms. No guarantees but no downside either that I can see. Will keep the forum posted. Works best at 50-70 degrees outside temp so I'll have to wait a bit here in TN but we always get a few unseasonably warm days in Jan. Here's the link to the product:

http://www.permatex.com/products/produc ... air-detail

$600 seems low. I think they don't know the labor involved or didn't look it up in AllData. I was quoted $600ish at first too, that was just off the top of the shop manager's head. The bill came out to over double that ultimately for just the RMS.

I don't know whether covering the weep hole is a good idea. I don't know if it serves any purpose other than just to let you know you have a leak.

So that's what that little opening is! I wondered about it. Yeah, if it is a weep hole then I guess I better scratch the sealer there. The oil will keep leaking and just accumulate probably causing even worse problems. Thanks so much, you really saved me there. The product has some potential though, I think. Probably would have done fine if there was a leak though the RTV between the upper & lower pans. What about rear seal stop leak products, like Bar's or AT-205 (recommended by Scotty Kilmer http://www.youtube.com/watch?v=HTT0sejhoOQ)? I hear that they soften and condition worn seals (supposedly) but are ineffective on cracked seals or if the seal sits in a groove. Any drawback to trying a bottle?

I've heard of both but never used either. I doubt either will work if your RMS is torn like mine was (see this thread). I would lean toward AT-205 Reseal since I've read good things about it on Bob Is The Oil Guy.

How much is it leaking?

About the size of a silver dollar most times (sometimes a bit larger, sometimes smaller) but thin, no pooling. Figured out how to post a pic!

That's a bit better than my leak was, mine leaked probably double that. I probably still could've ignored it and just topped off as required, but the leak was starting to get worse so I opted to replace the RMS.

I'd try the ATP-205 and if it doesn't help after a few thousand miles, start saving your pennies for the seal replacement. Actually, if you plan on keeping the vehicle for a few more years, start saving for the replacement now just in case the leak gets worse.

Yes, that's a good plan. I am going to try the "magic elixir" & will let the forum know how it goes. BTW, did a search here and didn't find anything of substance on ATP-205. But I'm glad to be the one who tests it. Been using Mobil One 10W-30 for last 3 or 4 oil changes. Some say that syn is more prone to leak than reg. oil although many use syn with no leaks. Also, for what it's worth, mine (wife's, actually) is an '03 QX4 with 150K. Very, very few problems since bought used in '07 with 97K. So, in spite of this issue, it's been a great SUV.

If you've been using M1 for the past few oil changes already without more leaks appearing, you're fine. Synthetic oil generally has more detergents than conventional oils, which allows it to clean "false seals" which are deposit build ups around a seal preventing it from leaking.

Why 10W30 vs 5W30? Where do you live?

I live in west TN where the winter temps are usually mild and summer is brutal. I decided to use 10W-30 after reading this in the user manual:

"SAE5W-30 viscosity oil is preferred for all temperatures. SAE10W-30, 10W40 viscosity oil may be used if the ambient temperature is above 0°F(−18°C)."

It never gets below zero here; rarely gets even to the teens. I guess I was leaning towards thicker-is-better for those 95 degree summers. If you were me, would you go back to 5W-30?

5W-30 and 10W-30 are in the same viscosity grade at operating temperature. 10W-30 is an obsolete grade and is probably the weakest Mobil 1 oil. I would switch to M1 5W-30, maybe in the High Mileage flavor which has more detergency and anti-wear additives, as well as extra seal conditioners which may slow the leak to boot.

Well, I tried 2 bottles of the AT-205 with no success. So, I took it to a trusted shop & had the seal replaced. Like you Towncivilian, my "$600" quote was erroneous; the final bill was about $1,100. BUT ... the drops are still appearing, just like before the RS replacement. So, I took it back to the shop & the owner said they checked it out & "tightened up some bolts". They kept it for a few more hours after driving it & observed no leak. So, I brought it home and the 1st morning thereafter, there was no leak. Whew, I thought! But, this am (2nd day) the spots were back; two side by side just like in my pic above. There is also oil again around the weep hole like in your picture. I will take it in again this week. Any thoughts as to why there are two side-by-side drops? If it was coming from the weep hole only, it would seem that there would be just one spot on the floor.

Belated follow up. Had rear seal replaced. But after awhile the small leaks are back. Took it back to shop & they kept it for days trying to see what was happening. Even pulled things apart again to recheck the new seal. They could not get it to stop. They surmise that there is a tiny crack somewhere on the mating surfaces, perhaps the crankshaft, which allows oil to bypass even a new seal. Fixing that would require major surgery; like maybe even a new crankshaft. Not worth it for an '03 QX4. I guess another alternative is a second opinion involving an examination and another replacement of the seal ... but that too is another $1K+ probably ... and it might not fix it if the tiny crack is in fact the culprit. But I have read at other forums that the seal install can be done poorly ... even though I have used this shop successfully for 20+ yrs. The other forums were Jeep & Corvette but I must admit that for those brands, yeah I can see it, but such a crack is very un-Nissan-like IMO. Any thoughts?

I"m not buying it. Even a tiny crack in a crank would not allow oil to pass until it was big enough to see easily. Not a scratch might cause it (if they scratched it while removing the old seal).

Either the seal they installed is leaking or the leak is somewhere else. I also don't believe they took it apart again. --Jerry

If there were a scratch on the mating surface of the rear main seal, they definitely would have seen it. Like I said above, this same situation happened to me - RMS replaced and there was still a small leak. It turns out the upper oil pan gaskets also needed replacing. There are two lip seals and the rest is grey RTV. The shop also replaced the RMS with a Nissan part (previously they used a Felpro) while they had the oil pan off. I think they did the lower pan gasket too for good measure (that one uses black RTV).

Time for a follow-up. BTW, I am also suspicious of the "slight crack" explanation of the mechanic but what is a poor consumer to do? I am not capable of pulling the tranny to back check the guy and a second opinion from another mechanic would cost a bundle. Anyway, from from the time I got the seal replaced till to the present (several mos.), I have lived with a slight spotting on the garage floor. It continues to be more like a stain than a puddle & never wider than a p0ker chip. Every 7 days or so I check the dipstick & have only added about 4 oz since June (also about 2K miles). But here is the reason for today's post: it seems to have stopped. One thing I did was switch about 3-4 mos. ago from full-syn to high mileage Valvoline, a concoction that has some additives and is supposedly not as thin as full-syn. It didn't help much to begin with but during the last 2 weeks I have seen only one incidence of a spot (strange huh? and it happened randomly in the middle of the 2 week period, wonder why just one)? It's too early to tout the hi-mileage Valvoline as the cure but I will keep the forum posted because if the leak doesn't come back, it is a cheap potential fix and thus is worth a try for others who have this problem.

PS - I am aware that the additives in hi-mileage oils are touted as being able to lube & rejuvenate old oil seals ... but as noted in my earlier posts, I got a new seal replacement. Thus, one reason for the sudden lack of leakage could be that the mechanic seated the new seal a bit c***-eyed and even though it has taken a few months, the additives swelled the seal and compensated for his botched job. Just a thought.

My QX4 had evidence of engine oil there too but no drop on the floor though. I cleaned and there isn't any oil there any longer! It just fixed itself.
152000 miles and still going like new.

I have a 2000 pathfinder with 262,000 miles and the same rms leak except mine is worse. Considering the cost of the repair, I just keep adding oil (about a quart every 800-1000 miles). I use Walmart brand 5W30 and the cost is only $2.64/qt. I have to buy over 400 qts to equal the repair cost so can go at least another 320,000 miles before equaling the repair expense!

Just an FYI

Nissan service manual states to do the RMS the correct way you have to lower the oil pan. ALLDATA includes this in their calculated hours to do the job.

I'm willing to bet neither of these shops did that.

docbentley, if I had a leak on a 262K miles vehicle I would deal with it just like you are doing. But you might want to increase your oil budget a bit give the high mileage oil a try for several quarts. If it works, you won't have to continually clean you garage floor. If it doesn't help, you are not out much $. It has been 3 weeks since I last posted & I have not had a drop of spilled HM oil. Hope I don't jinx myself with this post.