2004 Honda Odyssey Transmission Leak

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I have a 2004 Honda Odyssey, almost 125K miles, with a transmission leak from the case seal at the joint where the two transmission halves are joined. I got the van about 5 years ago with 54K miles, so have put over 70K on it since then. No transmission problems to this point other than the leak; it runs and shifts smoothly as it has since the day we got it. The fluid was replaced right after we bought the van with Valvoline MaxLife ATF and it has been replaced roughly every 20K miles since with MaxLife. It's been leaking for at least 2 months now and the level still hasn't gotten below the lower dot on the dipstick. The rest of the van is fine; the engine runs great and I've had little trouble with it except for some rather annoying electrical issues (starter, power mirror switch, power door lock, electric window regulator, and blower motor resistor). My local mechanic said I needed to take it to a transmission shop to get the case seal replaced to stop the leak. I called one very reputable (as in A+ BBB rated) tranny shop in our area and was given a rough price of about $1000 to replace the seal, due to all the labor it takes to remove the transmission, disassemble it, replace the seal and reinstall it. At only 125K miles on it, it's probably worth doing. I see the options here as the following: 1.) Continue driving the van as is and add tranny fluid every now and then as needed. 2.) Continue driving the van and, since I suspect this problem will only get worse otherwise, add some MaxLife tranny stop leak. But I'm concerned that might mess up the functioning of the tranny, and given the bad history of these trannies in earlier model vans, I would rather not risk that. What do y'all think about that? 3.) Go ahead and get the tranny seal replaced for $1K and replace the MaxLife tranny fluid with new MaxLife. 4.) Go ahead and get the tranny seal replaced for $1K and replace the MaxLife tranny fluid with Amsoil ATF (which I have about 9 quarts of after putting 3 quarts in my Saturn). 5.) Get the transmission rebuilt while the seal is being replaced (didn't get a quote for this, but probably around $3K total). Also not a very attractive option, since the tranny is working fine right now. 6.) Sell the van as is and buy a different one (which I'd rather not do right now as that will cost more $$$ than the other options). I may also try to snug up the case bolts holding the two halves of the tranny together; maybe they've loosened a bit over the years. Anyone know to what torque they should be tightened? Based on your experience, what do y'all think? Maybe there is another decent option I haven't considered. Thanks, and y'all have a Happy Thanksgiving!
 
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If the trans is out and apart I would spend the $ to have the clutch thickness checked. At 125k they should still have a lot of life left. Pay close attention to third gear clutch condition. I might consider putting in a reman torque converter and checking the condition of the bore for the torque converter charge valve. Charge Valve I have rebuilt a few of these now. The last one that I worked on had a catastrophic failure from the converter having low apply pressure under high load. It cooked the fluid to the point it sprayed from the vent. Third gear clutches ended up cooked, missing most friction material, and badly discolored.
 
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Originally Posted By: raffy
4.) Go ahead and get the tranny seal replaced for $1K and replace the MaxLife tranny fluid with Amsoil ATF (which I have about 9 quarts of after putting 3 quarts in my Saturn).
This^^^
 
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Why even pay a shop, just replace the ATF with AmsOil and the leak will fix itself, plus you don't have to worry about anything else ever happening with it. Of course, you need a sticker in the back window for this to be guaranteed. I might have the shop replace the seal and tell them to call you if they see anything during the replacement that would warrant further work. I know BITOG can be a great resource, but the guy who is staring at your opened transmission is clearly a better person to ask these questions to. Yes, though first you can try to "snug" the transmission bolts. Unless one is very loose it will be hard to overcome the corrosion at the specified torque value. So it should be obvious if that is in fact the problem.
 
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Personally, since it's apart I'd see at least if they can inspect the clutches like said above. The worst case is putting it back and then having to pull it out a few k miles down the road. If you plan to keep the van to 200k or so, this is probably worth it. Having said that, I have a 2003 with 145k and still shifts smoothly.
 
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I'd just drive it until it gets worse. It's a $1000 to stop a mild leak. I'd check the bolts for tightness just for kicks and grins. Seems to me, spending $1000 on a trans with 124,000 is not as wise, as if it dies at 150,000 you'll be pulling it out anyway for rebuild/replace. OR Have them pull it, and have them inspect and replace any items they see that might need it or are known wear items. Be prepared to spend another 500-1000 on this mini-rebuild. At least there is some peace of mind that the $1000 bought you more than just a new gasket.
 
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I'd just drive it too. $1000 for a leaky gasket is insane to me, on a 10 year old Honda van to boot. Just keep your eye on the fluid and go. My K1500 is my daily driver....and every week I have to check the oil because she's a burner, check the ATF because it wants to run into the transfer case, check my radiator because there is a crack in the filler neck, and pour an ounce or two in my leaky P/S reservior because the return hose is leaky. No harm done. Been that way for 30k miles, since I've purchased it.
 

raffy

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I will probably continue to drive the van as is for now. Last night I added 8 ounces of MaxLife ATF to it and it brought the level up to midway between the two dots on the dipstick. That was probably a bit more than the level it had been at before it started leaking, so it's maybe leaked out about 4 to 6 ounces over a 2 month period. At that rate, that would be about a quart a year I'd have to add, which isn't too bad. A quart of MaxLife is about $5 at Walmart, and that's a lot cheaper than paying $1K to get the gasket fixed! I'll just have to see if it gets worse and just keep an eye on it. I was wondering what you guys think of using the MaxLife ATF Stop Leak. Do any of you have experience using this (with any tranny, not necessarily a Honda) and does it work? Does it have any ingredient that might cause this tranny to malfunction? Thanks for all the comments and suggestions!
 
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Keep adding fluid as it needs. That transmission is very likely to fail at some point anyways, at which point you can decide what to do.
 
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Originally Posted By: bepperb
Yes, though first you can try to "snug" the transmission bolts. Unless one is very loose it will be hard to overcome the corrosion at the specified torque value. So it should be obvious if that is in fact the problem.
I agree, I would try this and add a bottle MaxLife ATF Stop Leak to bring the level to max.
Originally Posted By: raffy
I was wondering what you guys think of using the MaxLife ATF Stop Leak. Do any of you have experience using this (with any tranny, not necessarily a Honda) and does it work? Does it have any ingredient that might cause this tranny to malfunction? Thanks for all the comments and suggestions!
 

raffy

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Is Valvoline MaxLife synthetic? I didn't think it was, given how relatively cheap it is. MaxLife has been greatly recommended on the Odyclub forum as being helpful for extending transmission life on the 1999-2004 generation of Odysseys. Apparently lots of tranny failures occurred because owners insisted on using the Z1 Honda fluid when changing tranny fluid. There are people who have actually gotten over 200K miles on these transmissions without failure using MaxLife or a synthetic tranny fluid (such as Amsoil ATF). Ours has been just fine so far using MaxLife apart from this recent leak.
 
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Originally Posted By: antiqueshell
I have to wonder, did the synthetic MaxLife slip past a gasket seal designed ONLY for a dino based ATF fluid? I think that could have contributed to the problem.
I don't think (nor have I seriously encounter) one single instance of transmission (M/T, A/T, doesn't matter) seals being classified as "dino lubricant" or "syn lubricant" only type. I have, during the past 2+ decades of servicing automobiles, switched between full syn and dino gear oil (both M/T and A/T varieties) without introducing any leaks afterwards. To me, gear oil is gear oil. They exhibit consistent sealing capability so long as the lubricant is compatible. Q.
 
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Keep adding Max life atf as needed. If the trans ever needs a rebuild, have the seal fixed then.
 

hpb

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If it's a minor leak and the occasional drip it might leave on the driveway doesn't bother you, I'd just top it up as required and keep on truckin'. Can't say I've ever used transmission stop leak products, and I don't think I would, unless it was in a beater.
 
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Id just drive it, unless it is pouring out on your garage floor. For a drip here and there, flattened cardboard boxes work wonders :P $1000 for a drip on the floor is insane. No doubt its a big job but you may end up needing more than that done anyway. Imagine if it came back not leaking but worse off. Ive been smelling antifreeze for about a year in my car. I found a leak...not sure if I can tighten the clamp any more. I just wait for the light to come on and add cheap green coolant.
 
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