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Gucci2074

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Hey guys I got a 2005 LS Tahoe 5.3, the oil was changed I’d say close to a month ago and I remember looking under it and saw a little oil droplet just where the drain plug was about a week later after I changed it. I looked under it yesterday and I see this. How is the oil making its way through what it looks like the bolts and how can I fix this. Thanks for any help! Also my oil pressure has been reading fine where it should be it’s not low or high. It’s either straight up or just a tad bit from straight up. Also this truck has 265K on it and runs good.
 

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OR VietVet

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That drop is coming from above it. May well be the rear main seal assembly for the engine at the back. Especially with that many miles. Or could be leaking above there at the back of valve cover9s), the oil sender or back of intake. Look for the highest wet spot and sometimes requires at camera inside the bell housing to see the rear seal leakage.
 
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Gucci2074

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That drop is coming from above it. May well be the rear main seal assembly for the engine at the back. Especially with that many miles. Or could be leaking above there at the back of valve cover9s), the oil sender or back of intake. Look for the highest wet spot and sometimes requires at camera inside the bell housing to see the rear seal leakage.
That drop is coming from above it. May well be the rear main seal assembly for the engine at the back. Especially with that many miles. Or could be leaking above there at the back of valve cover9s), the oil sender or back of intake. Look for the highest wet spot and sometimes requires at camera inside the bell housing to see the rear seal leakage.
Thank you, how much do you think it will cost to repair the problem? If possible and not too too difficult I plan on trying to do it on my own
 

Joseph Garcia

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Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving sage advice from the knowledgeable folks on this Forum.

A cost to repair will be difficult to estimate, until you locate the source of the leak.
 
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Gucci2074

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MassHoe04

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Valve cover gaskets are easy-peasy, if that is what it turns out to be.
Rear main seal might be a little intimidating if you are a novice mechanic.

There is a Mobil synthetic oil that has seen very good results in restoring stiff rear main seals. I forget which one, but it is a synthetic for high-mileage vehicles that has conditioning agents in it that can help soften up seals.
I know there were a number of BMW and Jeep owners, who had first-hand experience in "restoring" RMS on their vehicles. Leaks stopped after a short time and never did have to tear anything apart. Only cost was the cost of a couple oil changes.

You might search up posts by Jerry Bransford on www.wranglerforum.com. He was one of the expert Jeep gurus. He was one of those, that had personal success with stopping RMS leaks with this Mobil synthetic oil on his vehicles.
Search up "RMS leak, rear main seal leak, oil".

Not saying there is a miracle cure out there, but it might be worth think about if your leak is not in the head cover gaskets above...

You may be lucky... The fact that oil drips formed by the two outer bolts, would lead me to think it might be a better chance of being valve covers rather than RMS. Clean off the oil and see if you can tell where the oil is traveling from.
 
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B-train

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My 2008 with the 6.2L looks just like that and it's the RMS. I looked from the top down with a bright light and mirror - dry. You can also get a view with a good light and mirror through the wheel wells sometimes too.

The RMS is an all day job with a lift. You have to pull the Trans and flywheel to get at it. If it's 4wd, then you get the joy of splitting the t-case from the Trans in order to get the Trans out and will need the t-case to Trans housing gasket as well.

I have 35k worth of new concrete by my shop, so it parks in the grass or gravel if it needs to sit out. A big piece of cardboard for under it in the shop at night. Total PITA, but for now that works. One day I'll get fed up and do the job. Crappy thing is the Trans was replaced by GM before I bought it and they didn't do it. Fail.......
 

Maximus05Escalade

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View attachment 382545

Hey guys I got a 2005 LS Tahoe 5.3, the oil was changed I’d say close to a month ago and I remember looking under it and saw a little oil droplet just where the drain plug was about a week later after I changed it. I looked under it yesterday and I see this. How is the oil making its way through what it looks like the bolts and how can I fix this. Thanks for any help! Also my oil pressure has been reading fine where it should be it’s not low or high. It’s either straight up or just a tad bit from straight up. Also this truck has 265K on it and runs good.
It could also be coming from rear valley pan gasket and/or valve cover gaskets. my underneath looks the same but a lot more oil. So, this weekend since my knock sensors are freaking out, I am replacing those the wire harness, intake gasket, valley pan gasket and valve cover gaskets. Hopefully solving the worst of my oil leak issue, knock sensor codes and deleting my automatic under vehicle oiling system. Another problem spot for an oil leak is oil fill tube which if you have it can be removed and oil fill cap will screw right into valve cover. That cleaned the top of my valley pan up, under throttle body just the entire surrounding area possibly contributing to the oil collection area we are speaking of. 05 escalade 255k LQ9 6.0.
 

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Thank you, how much do you think it will cost to repair the problem? If possible and not too too difficult I plan on trying to do it on my own
presuming it is the rear main seal then the transmission has to be pulled so typical cost is around $500-650
as already mentioned is could be from other sources and wind blow-by makes the oil go everywhere
could be coming from a variety of places or even more than one. valve cover, oil pressure sensor, oil cooler block off plate, oil filter adapter, rear main, dipstick seal, oil pan seal
I would suggest getting some purple power or whatever engine de-greaser of choice and spray it all over under and above at one of those diy car wash with a power wand and get under there with the wand and spray off everything as much as you can, take it home and park it over a clean large piece of cardboard and in the morning look under the truck for the wet spot and then look up from there. if there is nothing the first day then go drive it around a bit and try again.
 

MassHoe04

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If it is the RMS and cost is too much to deal with...
You know what they say: Make lemons out of lemonade.

Think of this situation as a built-in, perpetual, automatic oil change function.
Just keep adding oil to top it off and it changes itself!

Seriously, though...
If the leak (regardless of the source) is not enough to make you add oil constantly, is not damaging anything, interfering with safe operation or causing people behind you to go off the road due to a James Bond smokescreen...
You don't necessarily need to really stress over a few drips.
You just have to convince yourself a slight leak, even at a RMS, is not always a big deal.
The truck is coming up on 20 years old soon. Old trucks might leak a little.
 

Bill Hayes

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View attachment 382545

Hey guys I got a 2005 LS Tahoe 5.3, the oil was changed I’d say close to a month ago and I remember looking under it and saw a little oil droplet just where the drain plug was about a week later after I changed it. I looked under it yesterday and I see this. How is the oil making its way through what it looks like the bolts and how can I fix this. Thanks for any help! Also my oil pressure has been reading fine where it should be it’s not low or high. It’s either straight up or just a tad bit from straight up. Also this truck has 265K on it and runs good.
I had a 2007 NBS and had the RMS replaced. Then the pan gasket started leaking. Long story short, it turned out to be the driver side valve cover was bad. It contains the pcv valve. Replaced it and oil leak stopped. I am sure that if I changed the valve cover first, I would not have had to change the RMS. Pull the hose off the valve cover and blow into the valve cover with your mouth and a long enough hose. It should not have any back pressure and should feel like blowing through a soda straw.
 

Maximus05Escalade

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Thank you, how much do you think it will cost to repair the problem? If possible and not too too difficult I plan on trying to do it on my own
I had several other leaks like the ops, valve cover gaskets, valley pan gasket, oil fill tube, CSS, oil dipstick tube. started on top sense I had to do knock sensors anyway with most of the leaks making it to the same area and looking like yours. All pretty easy fixes. When it came to the rear main in order to try and buy time, I tried an oil additive for sealing rear main seals. I am not one to cut corners or have faith in additives fixing anything, but I put a bottle of Blue Devil rear main sealer in and seen results pretty much immediately from a steady drip on both corners of tranny to eventually nothing!!!!!!! The shit actually worked and worked fast. The only way it won't work is if seal is torn or has a chunk missing. $16.95 at any parts store. it's definitely worth a try. 05 Escalade, 255k miles, LQ9
 
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Gucci2074

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I had several other leaks like the ops, valve cover gaskets, valley pan gasket, oil fill tube, CSS, oil dipstick tube. started on top sense I had to do knock sensors anyway with most of the leaks making it to the same area and looking like yours. All pretty easy fixes. When it came to the rear main in order to try and buy time, I tried an oil additive for sealing rear main seals. I am not one to cut corners or have faith in additives fixing anything, but I put a bottle of Blue Devil rear main sealer in and seen results pretty much immediately from a steady drip on both corners of tranny to eventually nothing!!!!!!! The shit actually worked and worked fast. The only way it won't work is if seal is torn or has a chunk missing. $16.95 at any parts store. it's definitely worth a try. 05 Escalade, 255k miles, LQ9
Did you use the whole bottle?
 

Maximus05Escalade

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I had a 2007 NBS and had the RMS replaced. Then the pan gasket started leaking. Long story short, it turned out to be the driver side valve cover was bad. It contains the pcv valve. Replaced it and oil leak stopped. I am sure that if I changed the valve cover first, I would not have had to change the RMS. Pull the hose off the valve cover and blow into the valve cover with your mouth and a long enough hose. It should not have any back pressure and should feel like blowing through a soda straw.
This is absolutely 1 of the first things that should be checked and is 1 of the most overlooked.
 

89Suburban

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I had several other leaks like the ops, valve cover gaskets, valley pan gasket, oil fill tube, CSS, oil dipstick tube. started on top sense I had to do knock sensors anyway with most of the leaks making it to the same area and looking like yours. All pretty easy fixes. When it came to the rear main in order to try and buy time, I tried an oil additive for sealing rear main seals. I am not one to cut corners or have faith in additives fixing anything, but I put a bottle of Blue Devil rear main sealer in and seen results pretty much immediately from a steady drip on both corners of tranny to eventually nothing!!!!!!! The shit actually worked and worked fast. The only way it won't work is if seal is torn or has a chunk missing. $16.95 at any parts store. it's definitely worth a try. 05 Escalade, 255k miles, LQ9

I have been battling a rear main seal leak for quite a while now. Anywhere I would park it would leave behind 4 or 5 2" circular drips on the ground. Oil pan was always covered with windblown oil, as well as the crossmember, front sway bar, transmission pan, etc. You can imagine how ugly my driveway and parking spaces in the street and at my work look. They look like grease pits. I was loosing about a pint a week at least.

I saw your post and checked out that Blue Devil Rear Main sealer you mentioned and review. I looked it up on Amazon and read those reviews as well. I have an original 5.3 with over 340,000 miles on it. I figured what the hell and threw a bottle in last weekend. Ran it for the week. I pulled it into my shop to do some front end work. I could not believe it when I climbed under there. There was 2 drips on the oil pan, 1 drip on the crossmember, trans pan was BONE DRY. And it did not leak ONE DROP onto the floor while in my shop. I still don't believe it.

You the man! I will update as time goes on. For right now I am FLOORED. I'm gonna hit the warehouse floor at my work tonight and do another drip test and post pics of before stains and after.

I just took a some pics of my decimated driveway and sidewalk, and the entrance of my garage where I parked this afternoon is the last pic, not one fresh drop right there from today. IMPRESSED.


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