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  1. #1

    Default Rear Main Seal Leak Please help!

    I have a 99 silverado, and it has a steady leak from the rear main seal, i know that its a couple hundred bucks to get that fixed at a shop. And I'm a little hesitant to drop the transmission to replace the seal. I saw some engine oil additive or something that said it repairs the rear main seal to stop the leaks. I think is was called No Leak. I was wondering if this stuff worked and what brand to buy, because i noticed some other brands like Bar. Thanks!
    1999 Silverado 4.8L V8 2WD
    6" suspension lift by Fabtech
    3" body lift
    Toyo Mud Terrain 35" tires, 16" Weld Racing Rims
    Magnaflow cat-back exhaust
    K&N cold air intake
    Hypertech Performance Programmer
    Viper Security w/remote start
    Kenwood Speakers, 2 12" Kicker Comps
    Valor 7" flip out head unit

  2. #2
    Legend unplugged's Avatar
    Join Date
    Sep 2006
    High Deserts of SoCal


    All of those stop leaks prey on one's desire to avoid expensive repairs. I've used my share of Bar's Leaks, Wynn's, K&W Block Seal, Motor Honey etc. By and large, most do little to help. Then again they are typically less than $10 so what's the harm. Just start setting aside the money for the repair and don't let it go too long. It's a hand grenade and the pin has been pulled.
    There is no way to happiness....happiness is the way.:yipi:  _vXMYypuKMJFw671uF2ZPhjez_j-atRmcjM2zQKpQi1JSsB75/burb1.JPG
    High Desert SoCal
    93 K1500 burb (personal) 350 AT 3" Lift 250K+
    02 Honda Civic LX
    Looking for a 1990's Miata for an engine swap

  3. #3


    I know times are tough and moneys scarce out there but I gotta agree with unplugged on this.
    I used Bars Coolant System Stop Leak years ago as an emergency fix to get home, it was only 150 miles, by time I removed the radiator it had plugged up the radiator and cooling system causing the truck to overheat and warp the heads.
    So in a lubrication system just what does this stuff do? its designed to fill in a leak, lubrication systems need to keep oil flowing to be effective.

  4. #4


    The engine stop leak has a chemical which softens the rubber in ALL the rubber type seals in your engine. It may or may not work but it's worth a try since letting it leak may damage the engine if left to leak. Once the leak stops change your oil right away.
    I have a friend who stopped his front axle seal leak with this stuff so I know it works on rubber type seals.

    2004 SILVERADO 2500HD LS
    Pro Comp Leveling Kit
    285-75-16 Cooper ST All Terrains
    Pro Comp Programmer
    Bilstein Shocks
    Linux Bed Liner
    Tinted Windows

    Other rides:

    1967 Landcruiser <350 Chevy>
    1970 Camaro
    1990 Geo Metro Convertible
    2007 FJ Cruiser

  5. #5


    Thanks guys. I figured it wouldn't be the best thing for my truck, but it didn't hurt asking. I think I'm going to wait till Christmas break and drop the transmission to replace the seal.

  6. #6

    Default Rear Main Seal Leak in 99 Tahoe (with 350)

    My wife has a 99 Tahoe with the 350 block in it. It has a fairly major rear main seal leak and I have looked into replacing it. I have replaced the seal on other chevy small blocks and typically they are two-piece seals allowing for this to be done without removing the crank shaft or decoupling the transmission.

    I have searched everywhere but I can only find the seal as a one-piece replacement. Does anyone know of where I can get a two-piece seal.


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