OK, I had the 20K mile oil change on my job 1. Right before I brought it in, I noticed a few drops of oil on the driveway after I washed it. After crawling under the truck, I saw that the oil was dripping from the where the bell housing mates to the transmission. So I brought that to the attention of my dealer when I brought it in. I also told them that the coolant level has been a bit low since the last oil change. The had it all day and said they could not find where the oil was leaking from, nor could they find a coolant leak (funny, I told them the fluid was low since the last service, not that I've been loosing coolant).

Anyway, they kept it overnight so they could put dye in it and pressurize the system to see if they can see where the oil (or coolant) is coming from. They give me a call this afternoon and tell me that the truck is ready, they can't find the oil leak (after both a pressure test and driving it around for 50 miles to get the motor hot and to work it a bit). And get this, here's their theory; they think that they spilled oil on top of the motor at the last oil change and that it finally showed up on the bottom. Now, I can see this if it's only been a month or two since the oil change, but I don't drive it that many miles, maybe 11K miles per year. The 15K service was done the first week of July, five months ago. Should it take that long for oil to trickle down the motor, and wouldn't it carbonize because of the heat of the running motor? I took the rig all the way to Yellowstone and back pulling the family fiver, so the motor was running for hours on end.

They also did the venturi T customer service bulletin on the cooling system, said that it should take care of the coolant loss. When I told the guy that it's been low since the last service, he said that the venturi problem probably blew out the coolant from the start.

So, is sunshine being blown up my backside? I've gone to this dealer for years, both with this truck and my old F150. They found the last oil leak (turbo return tube) last summer on the first day and had it fixed in a week, so I think that their techs are OK.

At least the dye is still in the oil, so I'll be crawling under the truck every Saturday for a while looking for oil.

 

My 6.4 had an oil leak similar to yours. The dealer placed dye and it took them over 1 week to determine where the leak was coming from. They ended up replacing my short block due to a defect in the block allowing oil leak. I would press them to find the leak! There is NO way it took several months for SPILLED oil to drickle down to the area you have mentioned.

 

Another possibilty is machining oil finally making its way down the bellhousing. Common for the 6.0 and possibly for the 6.4. Same block.

 

I hear that it is the bed plate on most of these 6.4 when they find a leak on the ground. Something to do with the machined surface being off by a few thousands of a inch.

 

well, after three months and 1,200 miles (I only commute 400 miles per month), the leak finally showed up. It's the rear main seal. They are dropping the tranny to get at it. Should get it back in two more days.

 

glad they finally found the problem.

 

Better a rear main than the bed plate!!

 

i had to take my truck back two times to find the leak. the second trip they removed the starter with the engine running and exposed the bed plate leak. thought i would mention removing the starter.

 

Glad you got it fixed, thats a pain to change out on the older vehicles I worked on.

 

It's still in the shop. Mechanic snuck out early on Friday, must've been heading for the desert. Service writer at Ford was a bit pissed. I'm a bit more zen about it. I'd rather it get done right than be rushed 'cause the guy wants to leave for the weekend. Ford gave me a rental, it's a Kia, but at least it gets me back and forth to work. My truck only gets a workout when we go camping towing the fiver, so it's not that much of an inconvenience.

 

I have a very slight residue at the bell housing/transmission mating seam. It may drip onto the floor once a week and I drive it everyday. I can't quite tell for sure if it is engine oil or tranny fluid. There is never enough to see the color or get a good smell on it. The truck has only 2200 miles. Maybe if I put a white sheet of paper under the truck at night I can get a better idea. Can someone tell me what the bed plate is? Can it be fixed without jacking up the cab or other major work. I'm guessing that if you have to remove the starter to see it, that is not a good sign for an easy repair like a rear main.

 

requires removal of the cab...

 

I had sort of the same thing Matteberry..........Mine was the bed plate! Cab off the hole nine yards. Also did the Venturi and another flash. I'm at 23K

 

Finally got the truck back today. Paper work mentions that they replaced the main rear crank seal with "updated seal."

Is there silent recall on this?

Part number FMC 3C3Z 6701 B

I'll have to drive it a while to see how the ECM reflash changes things.

 

Fill in your favorite expletive, but the freaking leak is back and this time in less than a week. Goes into the dealer tomorrow. I hope it was a minor bonehead move by the tech and it's just a nicked seal, instead of a major bonehead move and some serious damage.