Replacing The Rear Main Seal*have teflon pt. number

mywhite89

Registered User
Are you able to replace the rear main seal without pulling the oil pan off? For some reason every time I do a rear main seal on Ford 3.8 the rear main ends up leaking. I have always used the fel-pro kit.

The transmission is out of the car so I can get right to it if its possible

Chris
 
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My buddy used an additive by the people that make the octane booster he said it was made for rear main seal leaks he figured why not it beats the $1500 to replace his (Lexus IS the motor has to come out) he said it stoped it for now so its worth a shot
 
Are you able to replace the rear main seal without pulling the oil pan off? For some reason every time I do a rear main seal on Ford 3.8 the rear main ends up leaking. I have always used the fel-pro kit.

The transmission is out of the car so I can get right to it if its possible

Chris
Yes, you can. And you will never have a better time to do it. :cool: just be sure to drill on the outer edge of the old seal to insert the screw that you need to pry it out. Iif you use a PFTE seal, its recommended not to use a speedie sleeve.
 
Yes, you can. And you will never have a better time to do it. :cool: just be sure to drill on the outer edge of the old seal to insert the screw that you need to pry it out. Iif you use a PFTE seal, its recommended not to use a speedie sleeve.

I used a sleeve on mine. What is a PFTE seal? I used the felpro rear seal that came with the gasket set and have had no leaks at all. I have replaced rear seals in the past and it seems to leak soon after. The sleeve just covers the serface where the seal contacts that had a slight groove.
 
PFTE = Teflon. Costs a bit more, but on the directions, its states "Use of this seal with a repair sleeve is not recommended".

I wasn't sure if "not recommended" meant there would be a problem with it or if they were implying that the seal would work even with the wear groove. I installed it w/o the sleeve and everything seems OK. I had replaced the original leaky seal with the normal Felpro seal and it leaked after about 3 months. Actually, in retrpsoect, I don't know that for sure.. I had to clean/seal the gap where the oil pan mates up at the back of the engine as it was leaking too. I did that by scrubbing the metal with brake cleaner 4-5 times and then laying down about 3 layers of black RTV Silicon. With those 2 things, its has not leaked for more than a year now.

I also used a normal seal+sleeve, and sillicon treatment, on the red car and its not leaking either. :cool:
 
PFTE = Teflon. Costs a bit more, but on the directions, its states "Use of this seal with a repair sleeve is not recommended".

I wasn't sure if "not recommended" meant there would be a problem with it or if they were implying that the seal would work even with the wear groove. I installed it w/o the sleeve and everything seems OK. I had replaced the original leaky seal with the normal Felpro seal and it leaked after about 3 months. Actually, in retrpsoect, I don't know that for sure.. I had to clean/seal the gap where the oil pan mates up at the back of the engine as it was leaking too. I did that by scrubbing the metal with brake cleaner 4-5 times and then laying down about 3 layers of black RTV Silicon. With those 2 things, its has not leaked for more than a year now.

I also used a normal seal+sleeve, and sillicon treatment, on the red car and its not leaking either. :cool:

I think I will try the teflon seal. The crankshaft was just polished so there is no reason for it to have rough spots at all. Where'd you get the teflon seal?
 
Autozone sells a teflon rear main seal for our cars. It is made by fel-pro, part number is BS40644
 
Good luck....Ever since this motor was built in 2001 the rear main seal has leaked a little. I've changed the seal 2 times, last time I even put RTV around the outside edge, and it still leaks.

David
 
Good luck....Ever since this motor was built in 2001 the rear main seal has leaked a little. I've changed the seal 2 times, last time I even put RTV around the outside edge, and it still leaks.

David

Tell me about it. Drives me nuts. Rear main seals are like oil changes, 3 months or 3,000 miles, which ever comes first.
 
Make sure its not the dripping from the oil pan rather than the seal. I've had this problem on both cars. I'll try to post some pictures later of what I'm talking about. :cool:
 
Just some small tid bits ive learned. Use thread locker under a sleave. Use rtv black around the rear seal where it seats. Let it dry over night. If you have even the slightest grove in your crank where the seal rides, its gonna leak. This is what my machinist told me. I now have 2 birds that dont leak at all and one has 50k on the rebuild. If you use a sleave make sure you use the installation tool they sell with it. One more thing, the oil you use will factor in as I one used mobil one on my 94 that never leaked a drop of anything with 80k on it and it only took about a week and it started leaking from everyware. I quickly switched back but it was too late. My wise machinest said to never use this in a old car. If it was new start out after break in with synthetic. Sometimes you need to get burnt to learn that fire is hot.
 
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I wouldnt use a Teflon seal for the rear main. Even the rubber one wears a groove in the crankshaft .. the teflon will wear it more. Sometimes when you first start the car, the teflon seal wont seal right away so it may leak a little bit at first.

- Dan
 
Mine is technically a (PTFE). Not sure what that means, parts guys said they thought it was teflon because they showed 2 listings for seals, a rubber one and the one I bought.

Richard I would definitely appreciate some pictures or what you are refering to.

Chris
 
Technically speaking, PTFE is Polytetrafluoroethylene ... Teflon is a registered trademark of the DuPont corporation. Teflon is one of the three fluorocarbon resins in fluorocarbon class composed wholly of fluorine and carbon. The forces binding the fluorine and carbon together provide one of the strongest known chemical linkages in a compact symetrical arrangement of atoms. The result of this bond strength plus the chain configuration is a relatively dense, chemically inert, thermally stable polymer.

So in other words, Teflon .. is PTFE.

- Dan
 
Mine is technically a (PTFE). Not sure what that means, parts guys said they thought it was teflon because they showed 2 listings for seals, a rubber one and the one I bought.

Richard I would definitely appreciate some pictures or what you are refering to.

Chris
This is the section that I sealed over. Also attached is a pic of the PFTE seal, and the repair sleeve. Note This is just for illustration purposes.. as the fine print says, "Fel-pro does not recommeded (sic) the use of a repair sleeve with this seal" So... I didn't.
 

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Ah ok, now I remember what it all looks like back their again. I'll have to check that out and make sure. So you just put some rtv over that area between the pan and the main cap and it worked?
 
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I cleaned it well with brake parts cleaner and steel wool. In particular, I scrubbed the gunk out of the gap using a thin piece of cardboard and, then pushed as much clean RTV into the gap as possible. It was sort of like caulking bathroom tile. Then 2-3 generous layers of RTV over the whole area. No drips. :cool:
 
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