It's not the seal, It's the crankshaft surface the seal rides on, Its machined to rough and not polished. My truck leaked at 300.miles
ford installed a speedy sleeve style seal with RTV silicone beteen the crank and the sleeve at my reqest. stopped the leak. 27,580 miles and still dry.

here is fords part# that thay installed 3C3Z-6701-AA

I have some pics of my truck apart In my gallery

 

My 2004 F350 6.0L Automatic (built Aug. 03) leaked from the first day I took delivery. My dealer claims most leaks go away by the first service at 5000 kms. It still leaks and I'm scheduled for my first service this week. I may have them swap the seal or I may wait, I can't decide.

I'd love to wait for an improved seal but even if they do develop a new seal, it could be a year or more before Ford offers it up at the dealerships.

Look at how long the new 'turbo mount' is taking. If that's the type of drawn out testing they do for a 'minor' vibration, imagine the testing they'd do for a new rear main seal!

just my $0.25

 

Just a quick summary on my April post Truck is back in the shop Second oil seal is going in tomorrow Just downloaded a picture of the oil seal area off the web Kind of confused I was a diesel mechanic for 23 yrs Can't figure why such a cheap looking oil seal is used in this type of app. No legiture spring, and no double lip seal to the mating surface Either the wear surface of the end of the crank is too soft, or the seal area of the seal is not mating 100% I think there is still such a thing as increased crank case pressure under a load If this doesn't fix the problem, I guess Ford can buy this one back or put a new engine in it.

 

I just checked my rear main after reading some of these posts, and sure enough there was a spot where oil was leaking. you'all have a lot of great incite about this, but i would like to know what everyone is doing about there leaks.

are you taking them in and getting them replaced?
does it fix it?
what about an aftermarket seal, has anyone tried one of these?

I sure would hate to leave my pick-up and drive a junk rental for a week if it isn't going to solve the issue. thanks for the feedback.

 

You might want to real ALL of the posts on this topic.

 

It would seem to me that with just over a 3000 rpm red line surface speeds would not be a factor like a gas engine turning 6000 or so. Also a diesel engine has to have more crankcase pressure than a gas engine, There should be a spring around the lip of the seal for extra pressure. Also Ford is using a lighter weight oil than I would like to see, If there is any runout in the crankshaft, play in the bearings or viberation it will cause the seal to leak. Sorry, but are you sure the manual trans model aren't leaking too?

 

Is it possible to replace with a differant type of seal? What is the dimensions on the seal? Maybe it can be crossed or an aftermarket cover can be made to accept a differant seal. I think they would sell here.

 

redline is 4250 rpm's

 

Still that is low compared to gas is it not? How often are you going to run at red line? 4250 rpm's is a lot for a diesel.
I am not trying to insult anyone here, Just trying to make a point about the seal design being used.

 

I just took my truck in to have the rear seal checked (Built Jan '03, 15,000 miles). Sure enough it's ;eaking. Although Ford calls it a "seepage. To them a leak is hen you can see it drip. They are replacing the seal next week. The diesel tech told me that the problem is not the seal. He said they now think it's the installation tool and technique they were using then. It didn't seat the seal far enough in on the crank. He says he replaces a couple per week. This is a fairly large dealership in Jacksonville, Fl with a big truck business.

 

BTW. He replaces the seal in about 4 hours. Says the only hard part is gettting to the torque converter bolts since there is no inspection plate in that tranny. So 2003 Stroke, you shouldn't need to drive a rental for a week or so. Just be careful which dealer you take it to for the work; the other nearby dealer's diesel tech didn't know there was a frame mounted fuel filter on the 6.0. Even when i asked him to look at the oicture in the owner's manual he said there was no such animal. My truck doesn't visit him any more.

 

I believe the point someone was making is that larger crank diameter results in faster surface speeds. I don't know how large this crank is, but I assume given the forces involved it is larger that an equivalent displacement gasser crank.

 

Sorry for your troubles I was only making a comparison. I will not do that in the future and I will stay with my 7.3.
Good luck

 

No trouble. Compare away, that's what this site is all about, right or wrong we all get to offer up our $0.25

 

Thanks for your support and good luck. I would have bought a 2003-4 if it wasn't for all the trouble with them for now. I know in time they will correct the problems and maybe then I will buy. Again good luck.