904 question. Please help.

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Badart

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Got a quick question for you. A little history on my 904 behind my fairly mild 318, TF-2 kit, 3000 stall other than that it's stock. The problem that I have is that sometimes when I drive it hard it will piss tranny fluid out of the bellhousing/convertor area and make a big smoke show. I mean it pours out and I leaves a trail down the street then it will just stop leaking. It has only done this 2 times in 350 miles. This 904 came with my basket case dart when I bought it and it shifts great with no slipping at all. It does not leak a drop other than that. Is it leaking around the input seal or is there something else in that area that would leak like this? I replaced the input seal the last time that I had the motor out just because and made sure that I didn't damage the seal when I reinstalled the convertor. The convertor is new and is a Boss hog street bandit. Thanks in advance for your help.
 
im no expert but just to toss something out there.

with mopars having differances in cranks and torque converters and harmonic balancers being internal and externally balanced.....could oyu have mismatched components? and when it gets to highrevs it goes out of balance enough to shimmy some fluid passed a seal?

doubt thats the case...just and idea

maybe the trans is overfull and it squirting out because of that?
 
Are you sure it's not leaking from where the dipstick tube goes in to the tranny?

if you think that's weird, my duster pisses tranny fluid all over the driveway (just sitting there not running) when it rains, but doesn't leak a drop any other time.
 
Most TF's vent into the bellhousing. Just how full is this tranny before you drive it "hard"?
 
DusterDude72 said:
im no expert but just to toss something out there.

with mopars having differances in cranks and torque converters and harmonic balancers being internal and externally balanced.....could oyu have mismatched components? and when it gets to highrevs it goes out of balance enough to shimmy some fluid passed a seal?

doubt thats the case...just and idea

maybe the trans is overfull and it squirting out because of that?
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It is the correct convertor. It is balanced. Thanks for the input.
 
possible that you have the wrong dipstick? and what shows correct on the stick.....would actually show as overfull on the correct stick?

sounds like its overfull and spewing out of a vent but again...I am no tranny man
 
DusterDude72 said:
possible that you have the wrong dipstick? and what shows correct on the stick.....would actually show as overfull on the correct stick?

sounds like its overfull and spewing out of a vent but again...I am no tranny man
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I will check that out. I am thinking the same thing the more that I think about it, but it is quite a bit of fluid. I am sure that someone out there has experienced the same thing.
 
Have you checked all around the belly of the tranny to see/feel if it might be coming from the vent area, or is it literally coming out of the dust shield area/vent, as you know most of the time the car is in a forward motion, so the fluid won't go in front of its origin of leak, it'll blow back, if all of the top & sides are dry above the pan, i'm sure its not coming from the vent, take the dust shield off & see if theres fluid on the inside area, this will pin point it too the front seal.

If it ONLY happens under hard throttle, its very possible its pushing past the front seal do to increased VB pressures, you 1st. need to make sure its not over filled.
 
ok, so you only filled it to the bottom of the dipstick, not enough fluid to keep it cool. plus you are probably using the radiator cooler. install an after large market cooler and don't use the one in the radiator.
 
All T/Flites have a vent in the front pump. I have seen these force fluid out, when using a Trans-brake application. The fix for that is to silicone the vent shut & install a GM style vent in the tailshaft housing.
I doubt that is your problem though. I would check your fluid level when its hot & idling in neutrel.
This is the best way to check your level. An external cooler needs to be added if you don't have one already. You will have more heat due to the loose convertor.
Are you using a quality brand ATF. I prefer a good quality Type-F fluid in my stuff.
Sometimes low quality fluid + mixing types together can cause the fluid to foam & expand, causing it to come out of the vent as well.
 
I have installed a small cooler from a past project in a spot where it may not be getting enough air flow. You are right and I think it is to small and both times that it has done it my tranny may have been hot. I will buy a big cooler and mount it in front of the radiator. BTW I am running ATF+4. Thanks guys.
 
Badart said:
I have installed a small cooler from a past project in a spot where it may not be getting enough air flow. You are right and I think it is to small and both times that it has done it my tranny may have been hot. I will buy a big cooler and mount it in front of the radiator. BTW I am running ATF+4. Thanks guys.
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I don't know about the ATF+4 for a performance application. I do know that it was designed to be used in Electronic transmissions to lessen the shock of elect. solenoids applyling certain funtions.
Anybody have any thoughts on using ATF+4?
 
I would make sure you are using the correct dipstick or that its fully seated atleast so you know your getting a correct reading.

as for using the radiator to cool the tranny.......just something to think of in the future.....not sure about the older chrysler radiators but I know atleast in the 90's and up there was a check valve inside the radiator that was known for going bad and after doing so it would stop transmission fluid flow and would tost your tranny so I always bypass it all together and put an external cooler on
 
nothing wrong with using atf+4 in 904....

but type 7 would work just as well...

never seen a 904 blow fluid out of the vent.....i got two of them with transbrake and never experience any of those problems..
 
70aarcuda said:
nothing wrong with using atf+4 in 904....

but type 7 would work just as well...

never seen a 904 blow fluid out of the vent.....i got two of them with transbrake and never experience any of those problems..
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The last & only T/Brake I had was in my Super Street Duster with a 727.
This was in 1995, it was a Tubo Action. This is how Paul @ T/A instructed me to install it. This may not be a concern on the newer brakes, as there are several different brands available now.
 
do not want to get of topic....but 727 needs vent moved with brake..
 
ATF+4 is fine, I don't like type F. I prefer Amsoil as it tolerates heat much better than anything else. Having said that I have Hyundai SP III in my 904 right now, couldn't afford the Amsoil at the time but it will be changed soon.

You do need to check and see if the correct dipstick and tube is being used. You may be overfilled and the extra heat is causing the fluid to expand and be forced out the vent. I've never experienced this with mine and I run a transbrake, a 4200 T/A converter and NO cooler. But mine is strictly a race car.

Do you have a deep pan and extended pickup on it? You could run that a quart low and see what happens.
 
I slept on it last night and I think the tranny is getting too hot and over flowing. I picked up the biggest Hayden HD trans cooler they had at the parts store and will be installing it today in front of my radiator later today. I will let you know what I find. The only issue is the 6" of snow that we got last night. Thanks everyone.
 
Well it warmed up today and the sun was shining so I topped off the tranny fluid and took the dart out for a drive. Let me tell you that I drove the wheels off of it trying to get it to leak. No leaks so i think that it was getting too hot and coming out of the vent hole. Go figure. We will see. Thanks FABO
 
Badart said:
Got a quick question for you. A little history on my 904 behind my fairly mild 318, TF-2 kit, 3000 stall other than that it's stock. The problem that I have is that sometimes when I drive it hard it will piss tranny fluid out of the bellhousing/convertor area and make a big smoke show. I mean it pours out and I leaves a trail down the street then it will just stop leaking. It has only done this 2 times in 350 miles. This 904 came with my basket case dart when I bought it and it shifts great with no slipping at all. It does not leak a drop other than that. Is it leaking around the input seal or is there something else in that area that would leak like this? I replaced the input seal the last time that I had the motor out just because and made sure that I didn't damage the seal when I reinstalled the convertor. The convertor is new and is a Boss hog street bandit. Thanks in advance for your help.
Click to expand...
I had the same problem once, It was a cracked snout on the converter. It did the same exact thing, it would only leak under hard acceleration but normal driving was fine.
 
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