How Can I Seal a Transmission Leak?

Checking Transmission FluidHaving a leak in your transmission can be a dangerous thing. It may seem like a few drips here and there won’t end up being a problem, but let’s do the math.  Assuming the puddle is big enough for you to notice, let’s say a puddle about the size of a dollar bill overnight, your transmission would lose about a quart of fluid every 10 days.  If your transmission holds 4 quarts of oil in the pan, then that’s a quarter of your fluid capacity gone in 10 days, and almost all of it gone in a month!

Having low transmission fluid can cause a lot of  expensive and frustrating problems.  First, the lack of fluid can cause higher than usually transmission temperatures.  The fluid in the transmission helps car heat away from friction points.  Less fluid means a higher temperature and a reduced capacity to cool the friction components allowing them to wear faster and potentially fail sooner.  An inadequate transmission fluid level also can mean poor lubrication if there is not enough fluid to reach the critical areas of the transmission also causing premature wear.  Lastly, a low transmission fluid level can cause dangerous drivability issues for your vehicle.  Transmission fluid is the high pressure operating fluid that cause gear smooth and accurate gear changes.  A low level can allow your vehicle to behave unpredictably and possibly even dangerously.

If you maintain your vehicle well and notice the transmission fluid leak, you may consider continuing to top of the transmission fluid level ensuring you don’t end up damaging your transmission due to a low fluid level.  Transmission fluid can range from 8$ a quart up to $15 a quart or more, so every 10 days you’re having to spend that much in replacement fluid, not to mention the time it takes to fill and check your fluid level every few days and continue to go to the auto parts store to purchase more fluid, funnels and clean up materials.

Transmission LeakThe most common leak points on automatic transmissions are the input and output shaft seals.  There is a shaft on the front of the transmission that slides either into the clutch plate or the torque converter that has splines on it.  This shaft transfers power from the engine to the gears in the transmission and will have an oil seal around it.  The output shaft similarly will have a seal that goes around the shaft, a slip yoke or the CV axles depending on the type of vehicle.  As these shafts or axles spin while your drive, over time they can start to wear down the seals around them.  Also, old fluid, low fluid or a lack of driving can cause these seals to dry out, harden or crack causing leaks.

 

Replacing these seals can often be a costly venture, and depending on the age of your vehicle and how long you intend to continue driving it, it may not be cost effective to replace them entirely.

You do however have another option.  Add BlueDevil Transmission Sealer next time you top off your automatic transmission fluid.  BlueDevil Transmission Sealer is specially formulated to restore the seals on the input and output shafts of your transmission to their original size and soft condition to permanently seal your transmission leak.  BlueDevil Transmission Sealer is guaranteed to seal your transmission leak!  Depending on the speed of your transmission leak BlueDevil Transmission Sealer can pay for itself in 2 weeks or less by saving you money on replacement transmission fluid.

BlueDevil Transmission Sealer

Pick up BlueDevil Transmission Sealer today at your favorite auto parts store like:

  • AutoZone
  • Advance Auto Parts
  • NAPA
  • O’Reilly Auto Parts
  • Bennett Auto Supply
  • CarQuest Auto Parts
  • Pep Boys
  • Prime Automotive Warehouse

Or, purchase BlueDevil Transmission Sealer directly from BlueDevil here.

Pictures provided by: www.rmauto.com and www.k100-forum.com

Related Posts

77 responses to “How Can I Seal a Transmission Leak?

        1. Devan-

          Yes, the BlueDevil Transmission Sealer would work to seal the leak you have described. You will not need a whole lot of product based on the small capacity. You should add 1 ounce of BlueDevil per every 1 quart of capacity. Expect to notice results after about 100 miles of driving.

          Thank You!

          -BDP

          1. Tee-

            It is very important to follow all of the directions properly to ensure best results. Using the full bottle will not harm your vehicle but you may want to siphon some of the fluid down and refill with the factory recommended transmission fluid.

            Thank you!

            -BDP

  1. Will this work in Manual Transmission (2007 Ralliart Colt) ? I have a very small leak on my input shaft seal (100ml every 6 months). Currently running Redline 75W90. Does it thicken the fluid at all ?

    1. Shane-

      The BlueDevil Transmission Sealer does not harden or thicken in any way. You should add 1 ounce of BlueDevil per every 1 quart of capacity.

      Results should be noticed after about 100 miles of driving.

      Thank You!

      -BDP

  2. Out of interest. Does this have any effects on cracks in the transmission casing? As in the metal? Thanks

    1. Robert-

      Unfortunately, the BlueDevil Transmission Sealer would not have any effect on an actual crack in the system. The product is specifically intended to rejuvenate and slightly expand rubber seals/gaskets.

      Thank You!

      -BDP

    1. Glenda-

      Yes, you may add the recommended amount (1 ounce of BlueDevil Transmission Sealer per 1 quart of capacity) of BlueDevil first and then top the transmission fluid to the proper level. You can expect to notice results after about 100 miles of driving.

      Thank You!

      -BDP

    1. Cindy-

      Once the product is added you will not start to notice results until the vehicle has been driven about 100 miles. Be sure you are using the correct amount, you should be adding 1 ounce of BlueDevil to every 1 quart of fluid capacity.

      Feel free to contact us at 888-863-0426 with any questions.

      Thanks!

      -BDP

  3. I Have a trans leak caused by bushing wear in my 2004 cad deville.Tech says it needs third clutch housing replaced($1600)
    Friends told me about Blue Devil for head gaskets.Will your trans sealer correct my problem

    1. Sonny,

      Thanks for your question about your Cadillac Deville. If your leak is still just a dripping leak for a gasket or seal then BlueDevil Transmission Sealer will restore the seal and stop your leak. You need to make sure to replace the worn bushing to get everything back into alignment before you try to seal your leak.

      Thanks again for your question!
      -BD Auto Pro

  4. I have a 97 Ford Taurus I don’t see a Leck or anything but it takes a long time to catch gear I already put 4 bottles of transmission fluid in it

    1. Dwayne-

      The best place to start would be to change your transmission fluid and filter and then double check to make sure the fluid level is correct. Having the transmission fluid level too high or too low can cause the transmission to act up and not shift properly.

      If you are still experiencing the hard shifting after changing the fluid and filter and topping to to the proper level then you may want to have your Taurus looked at by a transmission specialist.

      Thanks!

      -BDP

        1. Ashley-

          The BlueDevil Transmission Sealer is intended for leaks that are seeping or lightly dripping from the system. Based on your description, you may be losing fluid a little too quickly for the product. Typically you would start to see results after about 100-200 miles of driving. If you would be losing all of your fluid before you got to that point, you would not be able to keep the sealer in the system long enough to get the benefit of it.

          Thank you!

          -BDP

  5. Hello I have a 2002 Hyundai elentra. I have a transmission leak and was told that I needed to have my seal replaced. Sometimes I have a puddle of transmission fluid and other times there are just drops. It drives okay. Bt I have felt my car drive like it was dragging then it will jump real hard into gear then drive perfectly fine. I was wondering if I could add the blue devil sealer to fix the problem to my car ?

    1. Ashley-

      Thank you for asking about your Hyundai Elantra. Based on your description, we would recommend using the BlueDevil Transmission Sealer. You will be using one oz of the product per quart of fluid in the system and should expect to see results after about 100-200 miles of driving.

      Thank you!

      -BDP

  6. Will the Blue Devil work on the front seal of a Borg Warner Velvet Drive Marine transmission. I would like a quick reply because I have to get the boat back in service.

    1. Jim-

      Yes, you would be able to use the BlueDevil Transmission Sealer for your boat. You will be using one oz of the product per quart of fluid in the system. Feel free to contact our technical support line at 888-863-0426 with any other questions.

      Thank you!

      -BDP

  7. I have an 87 Chevy blazer, it’s leaking transmission fluid out off the front of the transmission, I pour a quart in and almost immediately it’s leaked out. what do I do

    1. Andrew-

      The leak you are experiencing is too extreme for what BlueDevil Transmission Sealer is made to fix. At this point we recommend taking it to a transmission specialist.

      Thanks!

      -BDP

    1. Angelo-

      Yes, we recommend using BlueDevil Transmission Sealer to stop your leak. You should add 1 ounce of BlueDevil per every 1 quart of capacity; most likely you will not need the full bottle. Expect to start seeing results after about 100 miles of driving.

      Thank you!

      -BDP

  8. I have a 1994 Ford Explorer. It is leaking about 1 quart of fluid every 2-1/2 days. Im not ready to have to go thru the extensive labor especially without a lift to the drop the transmission right now inorder to replace the front transmission seal. I wanted to know if your Blue Devil Transmission Sealer would do the job and hopefully save me the grief of having to drop the transmission at this time for a leaking seal. Once again it leaks about 1 quart of transmission fluid every 2 to 3 days, which is a pretty serious leak and costly. Im hope your product will be my savior.

    1. James-

      Yes, based on your description we do recommend adding the proper amount of BlueDevil Transmission Sealer to your Explorer. You should add 1 ounce of BlueDevil per every 1 quart of fluid capacity. Once the product is added you can expect to start seeing results after about 100 miles of driving.

      Thank you!

      -BDP

  9. I posted on your blog just two days ago. I went ahead and purchased the Blue Devil Transmissin sealer that very same morning. I added the proper amount of the product as instructed and drove the car 250 miles sense then. Right away I seen that the puddle of tansmission fluid that was being left on my drive way was getting less and less. This morning I was parked in a new spot over night and now would’nt you know, I didnt find one bit of transmission fluid on the ground under the car.
    This is great news for me and I hope it will last for a long while. Im impressed considering I have already tried many different brands of transmission sealers that are on the shelves with no results to fix the problem. Just more wasted money was all. If I had only tried Blue Devil first I would have saved more money. I deffinitly will tell everyone I know that has these type of leaks to try Blue Devil first to fix there problems. I cant thank the people who came up with and made this product enough. Thank You So Very Much. Sincerly, James Muir.
    A Very Satisfied Consumer.

  10. Hello,

    I have a Golf Cart Differential that is leaking oil slightly at the Input shaft. This product seems like it would work, but the golf cart is actually filled with motor oil (per the manufacturer’s recommendation). Would this product also stop the motor oil from leaking through the seal?

    1. Andrew-

      Yes, we would recommend adding BlueDevil Oil Stop Leak to help stop the oil loss you are experiencing. Use 1 ounce of BlueDevil per every 1 quart of capacity. Expect to start seeing results after about 1 – 2 hours of use.

      Thank you!

      -BDP

  11. I have a leak on a BMW X3 2004, GM Automatic transmission. It is very small mayne 1/2 quart a month or less, a few drops every night. It looks like it is coming from the mechatronic seal. Will this product work for bmw’s with GM transmissions?

    1. Daniel-

      Yes, BlueDevil Transmission Sealer is compatible and safe to use in your BMW. Based on the capacity of your transmission we recommend adding 8 ounces of BlueDevil Transmission Sealer for proper treatment. Expect to start seeing results after about 100 miles of driving.

      Thank you!

      -BDP

    1. Charmmorro-

      You should add the proper amount of BlueDevil Transmission Sealer to address the transmission fluid leak; 1 ounce of BlueDevil will treat 1 quart of transmission fluid. For the oil leak, we recommend using BlueDevil Oil Stop Leak, you should add one 8 ounce bottle. Once the products are added you can expect to start seeing results after about 100 miles of driving.

      Thank you!

      -BDP

  12. Hello I just purchase blue devil product I think I made a mistake by putting the transmission fluid first then the bluedevil.. Is it going to work anyways?? Or is there any difference about putting the bluedevil first the transmission fluid after ??

    1. Nelson-

      There is no real difference in adding transmission fluid first or adding the BlueDevil Transmission Sealer first, as long as you are using the proper amount of the product and you did not overfill the system. You should expect to see results after about 100-200 miles of driving. Feel free to contact our technical support line at 888-863-0426 with any other questions.

      Thank you!

      -BDP

  13. Hi I have a 95 t bird front transmission Leaks fluid a lil puddle a day I bought the blue devil my ? Is the 4 quarts I’m putting in do I add 1 ounce per quart or how many quart that’s in transmission an torch converter

    1. Walter-

      Thank you for asking about your Ford Thunderbird. You would be using one oz of the product per quart of fluid in the system. If the transmission system holds 4 quarts of fluid, you would be using 4 oz of the product.

      Thank you!

      -BDP

        1. Deidra-

          Thank you for asking about your BMW 530i. You should be using one oz of the Transmission Sealer per quart of fluid in the system. It looks like your vehicle only holds a little less than 2 quarts of fluid so you should be adding 2 oz of the product. Feel free to contact our technical support line at 888-863-0426 with any other questions.

          Thank you!

          -BDP

  14. Good Day, I want to use blue devil trans sealer on a GM transmission with dexron VI (valvoline), I have a very small leak that looks like it is coming out of the front seals. My only concern is that I already added lubegard red to condition my transmission, will adding blue devil be a problem if the other additive is in there, the other additive is not a seal sweller.

    1. Mario-

      No, it would be safe to add BlueDevil Transmission Sealer at this point. You should add 1 ounce of BlueDevil Transmission Sealer per every 1 quart of fluid capacity. You can expect to start seeing results after about 100 miles of driving.

      Thank you!

      -BDP

      Thank you!

      -BDP

  15. 1990 Cadillac Deville 4.5, Leaking oil, DIAG:
    Leaking from bottom pan, side pan, & both axles.
    Shifts good, rebuilt 2 years ago. Tech says tranny is in great condition except the mentioned leaks. Is this a job for the Blue Diablo?

    1. Mark-

      Thank you for asking about your Cadillac Deville. Based on your description, we recommend using the BlueDevil Oil Stop Leak. The Oil Stop Leak is a universal application and would treat leaks coming from the oil pan gasket, valve cover seal, rear main seal, transmission, etc. As long as you are not losing fluid too quickly, you would be a good candidate for the product. You should expect to see results after about 100-200 miles of driving.

      Thank you!

      -BDP

      1. Well, I meant the trans, anyway I put 8oz. In & drove 140 miles. The cars been sitting now for 24 hrs & I $h!+ you not there’s not a drop on the floor!
        I am genuinely shocked! For anyone who has a bad tranny leak, be advised, my case / pans are not cracked, the tranny was rebuilt @ 2 years ago, & operating very well. I think my gaskets started cracking after sitting in below freezing temp at @ 8000 ft above sea level. My question to bdp at this point, how does the tranny seal effect the oil & the mechanics within the transmission? How can you prove it?

        1. Mark-

          Thank you for the excellent feedback, we are glad the BlueDevil Transmission Sealer was able to stop the leak in your vehicle! The product is only affecting the rubbers in the system. It is revitalizing and reconditioning the rubber seals or gasket, and will swell them up or expand them back to their original state. The product would not have any affect on the oil or the mechanics within the transmission itself.

          Thank you!

          -BDP

  16. I have a leak in the transfer case of my 4×4. The transfer case uses 75w-90 gear oil. The leak appears to be coming from the gasket between the transfer case halves (the case is splittable when disassembled). I believe the gasket is paper, not rubber. The case is NOT leaking from the rubber input or output shaft seals. Will the transmission sealer work on the paper gasket between the transfer case halves?

    1. Nick-

      Nick-

      BlueDevil Transmission Sealer is specifically designed to stop oil loss from rubber seals & gaskets. Unfortunately, we do not manufacture any products that are made to stop the type of leak you are experiencing.

      Thank you!

      -BDP

  17. I have a 2002 audi a4 Quattro the other day I was backing out and the car died an I stared it and drove about 5 miles and looked back smoke was barreling out the back from the fluid being lost looked under and transmission was pouring out fluid looked under and it was coming out from between the bellhousing and engian block so I’m thinking blew the input shaft seal you think this might help I reall don’t want to pull the trans

    1. Eric,

      Thanks for your question about your Audi A4. The real question for us is why your car started leaking so much fluid so quickly. If you’ve had a slow leak for a long time that has been getting steadily worse then you might try using BlueDevil Transmission Sealer to stop the leak. If the leak has suddenly gotten worse it may be an indication of a bigger problem like a worn bearing allowing the shaft to wobble or or something else misaligned so it may be wise to remove and inspect the transmission to ensure there aren’t any bigger problems.

      Thanks again for your question!
      -BD Auto Pro

      1. I have a Jeep Grand Cherokee Laredo that is leaking from the transmission pan between the transmission and pan even after I have replace the pan and gasket, will the transmission stop leak help stop this leak

        1. Sheilah-

          Yes, we recommend using the proper amount of BlueDevil Transmission Sealer. You should add 1 ounce of BlueDevil per every 1 quart of fluid capacity. Once it has been added you can expect to start seeing results after about 100 miles of driving.

          Thank you!

          -BDP

    1. Joe-

      Based on your description, we would recommend using the BlueDevil Transmission Sealer for your vehicle. You should expect to see results after about 100-200 miles of driving.

      Thank you!

      -BDP

  18. I have a leak in the front seal on my transmission 94 Buick Roadmaster will this product seal it leaks about a quart or two a day I have tried everything else and do y’all have a product for conditioning and shudder

    1. Kenneth-

      Thank you for asking about your Buick Roadmaster. From the sounds of it, you may be losing fluid a little too quickly in order for the product to be effective. Typically, you would start to see results after about 100-200 miles of driving. If you are losing fluid too quickly, you would be losing the product just as quickly, and wouldn’t really be able to keep it in the system long enough in order to get the benefit of using it. A hard part repair may be your best option.

      Thank you!

      -BDP

  19. I have a 2004 Chevy trailblazer. I have a leak on the transmission how many ounces of the blue devil should I put in?

    1. Jesus-

      Based on the transmission fluid capacity of your 2004 Chevy Trailblazer, we recommend adding 11 ounces of BlueDevil Transmission Sealer for proper treatment. Expect to start seeing results after about 100 miles of driving.

      Thank you!

      -BDP

  20. I recently got an Chevy HHR and I was told from the owner it had a worn transmission seal, and as far as she knew it wasn’t leaking yet but would begin too soon if it wasn’t replaced. Would this keep the leak from starting?

    1. Josey-

      Thank you for asking about your Chevy HHR. The BlueDevil Transmission Sealer will revitalize and recondition the rubbers in the system and expand them, or swell them up, to get them back to their original state. You will be using one ounce of the product per quart of fluid in the system. Feel free to contact our technical support line at 888-863-0426 with any other questions.

      Thank you!

      -BDP

  21. I have a 2004 Chevy trailblazer. I have a leak on the transmission how many ounces of the blue devil should I put in? Would the blue devil harm my transmission? If I put the whole 16 ounce bottle?

    1. Jesus-

      The capacity of the Transmission on your Chevy Trailblazer is 11.2 quarts. We recommend adding 11 ounces of BlueDevil Transmission Sealer to properly treat your vehicle. Expect to start seeing results after about 100 miles of driving.

      Thanks!

      -BDP

  22. I have a 2004 Dodge Stratus, 2.7 V6 with 260,000 miles on it. I appears my transmission pan is leaking, will this seal that long enough until I can get my car in the shop to have the seal?d

    1. Debbie-

      Thank you for asking about your Dodge Stratus. As long as you are not losing transmission fluid too quickly, you would be a great candidate for the BlueDevil Transmission Sealer. Typically, you would start to see results after about 100-200 miles of driving.

      Thank you!

      -BDP

  23. I got a question for you and Blue Devil…I have a 1994 gmc sonoma the transmission started leaking terribly on my way to work one night. I wasn’t sure what the problem was (still don’t). It is leaking quite a lot of fluid between front of pan and cover plate on trans. My question is: will Blue Devil seal this problem? p.s. it only leaks when engine is running

    1. Chuck-

      Thank you for asking about your GMC Sonoma. Based on your description, you may be losing fluid a little too quickly for the BlueDevil Transmission Sealer to be effective. Typically, you would start to see improvement after about 100-200 miles of driving. Unfortunately, it sounds like you may lose the product before it would get a chance to seal. A hard part repair may be your best option.

      Thank you!

      -BDP

      1. do you think if i add more and more product as i add trans fluid it might repair it in 100-200 miles?
        1 ounce to 1 quart trans fluid?

        1. Chuck-

          You really only want to add the recommended amount of the product. You will use 1 oz. of the product per quart of fluid in the system. Unfortunately, if you are losing fluid too quickly, you would lose the product just as quickly, and wouldn’t really be able to keep it in the system long enough in order to get the benefit of using the product. Feel free to contact our technical support line at 888-863-0426 with any other questions.

          Thank you!

          -BDP

Leave a Reply

Your email address will not be published. Required fields are marked *