Rear main
Posting Guru
Joined: Jan 2004
Posts: 1,736
Likes: 1
From: Monroe, MI
Take it into dealer. My 05 appeared to have same problem. Infact, when dealer mechanics looked at problem first impression said rear main. As they delve deeper they found my turbo hoses were loose and they just happened to be dripping in the perfect place. Hopefully thats all it is.
Senior User
Joined: Jan 2004
Posts: 392
Likes: 0
From: Orange County, CA
I think my truck had about 600 miles on it when the dealer replaced the RMS on my 06. I now have 4100 miles and there is still oil on the bell housing. Either my new RMS leaks too, or it never was leaking and the oil is coming from somewhere else. I know almost all the oil leaks on these trucks find their way to the bell housing and some can be difficult to locate, even with tracer dye. Mine doesn't leak enough to drip on the driveway so I'm not going to do anything about it for now.
If I were you I would take it back to the dealer and have them take a look at it. They will probably put dye in the oil and ask you to come back after a few hundred miles.
If I were you I would take it back to the dealer and have them take a look at it. They will probably put dye in the oil and ask you to come back after a few hundred miles.
New User
Joined: Jun 2005
Posts: 17
Likes: 0
From: Poway, CA
Rear main leaks
I had a few spots on the driveway at 17 miles (yes, that's 17 !) and the dealer did the rear main seal. A few more spots around 1500 miles, rear main seal again. A few more spots around 3500 or so, dealer replaced an injector o-ring and THE REAR MAIN SEAL ! A few more spots around 5100 miles, this time I told the dealer to fix it or take it back. They found a bad o-ring at the cam position sensor and to date (8500 miles) no more oil spots (knock on wood). I can identify with anyone who is frustrated by oil leaks in this rig.
New User
Joined: Sep 2005
Posts: 2
Likes: 0
I had an oil leak on my 05 at the rear at 12k, thought it was the rear main, when the tech actually got in there, he found out it was the bedplate at the corner where there is silicone applied, there wasn't enough, so he fixed that up and replaced the rear main anyways. Which I think you have to do when the bedplate is removed. I also had leaks up front at 5800, he replaced everything known to leak, including the oil pressure regulator o-ring. and the harmonic seal. Since this the second 6.0 I've had oil leaks on, and my dealer knows the probs I've had and trys to prevent future visits.
Junior User
Joined: Aug 2006
Posts: 78
Likes: 0
Rear Main
Man I hope this doesn't become a problem with the rear main. I had my 06 F250 that leaked the tiniest bit at the bell housing. I took it to the dealer and what do you know it was the rear main seal at 3,250 miles definately under warranty. I better keep an eye that this leak doesn't reappear.
Jäger
Joined: Jan 2005
Posts: 5,491
Likes: 5
From: Northern Arizona
24,383 miles on my truck. I noticed a drop of oil on the bellhousing every time I changed the oil/filter starting at 1,000 miles. Never a drop on the ground under the truck, ever. Last 2 oil changes, no more oil drop on the bellhousing! It wasn't leaking enough to drip on the ground or notice on the dipstick so I left it alone.
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Junior User
Joined: Aug 2006
Posts: 78
Likes: 0
kepler4
Haven't noticed any leaks since but I plan on keeping an eye out. This is my first new truck and also my first diesel. I was just under the truck admiring it 
when I noticed a small amount of oil at the bell housing and like yours it really wasn't spotting the driveway or garage floor. I left it go for 3K miles and then took it to the service dealer.
when I noticed a small amount of oil at the bell housing and like yours it really wasn't spotting the driveway or garage floor. I left it go for 3K miles and then took it to the service dealer.
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Elder User
Joined: Jul 2006
Posts: 577
Likes: 0
From: Stevens County, WA
I noticed that the frame on the passenger side right around the upper shock absorber mount is damp with oil. I can't locate the source, even getting up in there with a flash light. It's a real slow leak. anyone have any input on what would get that area wet with oil? I had a the RMS replaced about 1500 miles ago. There's nothing on the bellhousing.
Got Diesel?
Joined: Jan 2004
Posts: 4,345
Likes: 21
A good shop will add UV oil dye and have you run for 600 or so miles. Then when you stop back in they can use the ultra-voilet light and see where, if any, it is leaking from.
Yes, this motor has had issues with oil leaks, but if it takes more than 1 trip, then the mechanic is not diognosing it correctly. There is no reason to fix a rear-main, if its a cam sensor and so on.
I thought I had a rea main, and all mine was fund to be was the dreaded "too much" assembly lube on the rear-main... not oil... just very thin assembly lube that leaked out. They cleaned it up and all is well.
Again, have them use UV dye and try to get them to diognose it right the first time... it saves them time and money and you money!!!
Just my .02 worth...
Yes, this motor has had issues with oil leaks, but if it takes more than 1 trip, then the mechanic is not diognosing it correctly. There is no reason to fix a rear-main, if its a cam sensor and so on.
I thought I had a rea main, and all mine was fund to be was the dreaded "too much" assembly lube on the rear-main... not oil... just very thin assembly lube that leaked out. They cleaned it up and all is well.
Again, have them use UV dye and try to get them to diognose it right the first time... it saves them time and money and you money!!!
Just my .02 worth...
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