FEL-PRO BS 40640 Engine Crankshaft Seal Kit for Chevrolet Silverado 1500

I purchased 2 different seals because they were cheaper but I end up dropping the transmission 3 times because none of them work, this one works perfectly, 4 months already and no leaks.

There's a reason why felpro is the best when it comes to sealing, the fit and quality speak for themselves

Bought a used motor and seeing how vortechs are notorious for leaking rear seal on back of motor, I got this to replace so I won't have that issue. So far it is doing what it is suppose to. Was a real good buy

Solid

The media could not be loaded. I replaced this seal while I was doing a transmission overhaul. The truck is up and going and the seal is working great. The install can be a little confusing for people who haven't used these before. The lip of the seal is different than a traditional rubber seal and the seal is narrower than the origional seal. Ensure the small thin lip (dust seal is facing it away from the engine and towards the transmission. Also the entire seal is rubber or almost what seems like a graphite material instead of steel so you need to use care to not deform it during pressing in, however, being all rubber it presses in easier than the traditional steel seals. Just make sure you get it all the way down and flat in it's bore; use the install tool while you're pressing it into the housing and while installing the housing/seal into the engine to keep from distorting it. One more important thing to mention, and its hard to wrap your head around this as it goes against conventional seal installation practices is: You do NOT...i repeat do NOT use oil on this seal or it's mating surface. Like I said this seal is a harder rubbery material maybe impregnated with graphite? If you do use oil I hear they will leak for sure. I have installed many of these (PTFE I believe is the the material,) mostly on Cummins diesels and never used oil and never had a leak. They come with a grease for vacuum testing purposes, I wipe that off, just make sure you don't leave any lint on it. Research it. PTFE.

So i purchased this to repair the rear main seal. Originally i received the kit that has this copper/aluminum gasket with black silicone on it as pictured in the photos. I had to return that kit because the seal was damaged. I was sent another bs40640 kit also branded fel-pro. This one however was a steel gasket with blue silicone.Frustrated because i didnt know if these parts were original i went to the dealer to buy it. They wanted $80 for the gasket only and it looked EXACTLY the same as the copper/aluminum with black silicone. I then passed by autozone to look at the same kit and they had the blue silicone one one.The round seal on both kits appeared exactly the same.It seems two companies are making these gaskets for felpro so theyre both "authentic". I would have preferred the aluminum/copper colored one as the original one that came out of the vehicle was also aluminum. The steel one had a slightly poorer fit. I ended up installing the blue one and initially there is no leaks. Ill update on longetivity as im only about two weeks into install.

Fixed the rear main seal leak on my 2007 Silverado with 5.3l LY5 that started around 320,000 miles. Changed it out on a Saturday and not a drop and truck now has 330,000 miles and the pan is dry with no leaks. I would normally go GM or Cometic but Felpro has stepped up and started making quality gaskets agin it seams.

Easy to install.( once transmission is removed) Fits and works as it should.