904 tranny problems

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Frodee

Frodee

Off center a bit
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My 904 was rebuilt about 5,000 miles ago but since then restored my car and did an engine swap to a 408 from Blue Print engines and changed torque converter to a ATI set up for the street not the strip. Engine produces 500 ft. ft. lbs. of torque.
I have 2000 miles on the car since it's been back on the road and noticed it started slipping into third gear when giving it a bout half throttle.
Was told the bands needed to be adjusted so I did and helped. I adjusted both bands at 72 inch lbs. then backed the adjusting bolt on the forward ban 1 1/2 turns and the rear band
2 3/4 turn. After 40 miles the tranny was slipping in reverse so headed for home and noticed starting out from a stop it didn't want to go in 3rd gear but it tried to but would just slip
1st and 2nd gear worked fine. When I had the pan off I changed the filter and fluid and all was clean some sediment on the filter but nothing bad and oil was clean.
I'm no transmission guy just trying to learn and I know the tranny can't handle that much torque from what I've been told but not racing it just a road car that I like to stomp on the gas now and then.
 
The front clutch right behind the pump is used for reverse and third. When it wears out, you lose third; and reverse usually becomes delayed with a harsh engagement. Easy fix. Is your kickdown hooked up and adjusted properly? If it's not right, third gear bites the dust.
 
CudaFactHackJob said:
The front clutch right behind the pump is used for reverse and third. When it wears out, you lose third; and reverse usually becomes delayed with a harsh engagement. Easy fix. Is your kickdown hooked up and adjusted properly? If it's not right, third gear bites the dust.
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Just looking the kickdown adjustment up on the internet and your right It's out of adjustment as far as I can tell.
 
Ya, some guys will tell ya that you can just shift it manually, but that fries the third gear clutch and sometimes the second gear band because they don't apply hard enough and quick enough under heavy throttle.
 
CudaFactHackJob said:
Ya, some guys will tell ya that you can just shift it manually, but that fries the third gear clutch and sometimes the second gear band because they don't apply hard enough and quick enough under heavy throttle.
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That's what I was told and I guess that's not true.
Also finding out that the adjustment is different from one website to another.
 
We're pretty heavy into doing it right. You get that kd adjusted right; with the right linkage, and you'll think you got a shift kit. Course that's after you drop out that front drum and replace the frictions...easy peasy.
 
CudaFactHackJob said:
We're pretty heavy into doing it right. You get that kd adjusted right; with the right linkage, and you'll think you got a shift kit. Course that's after you drop out that front drum and replace the frictions...easy peasy.
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Easy for you I don't know what the front drum and frictions are but I guess I'll find out.
I'd like to fix it myself just to learn but am afraid of screwing up again.
 
Have you ever rebuilt a carburetor? Cuz just dropping out the front drums and leaving everything else intact is a lot simpler to do.
 
Yes. Then remove the valve body. Have you done that before? Nothing to watch out for there except a spring or blocker rod might come out of the accumulator. Just take it down slow and you'll see how it goes back in. I always like to remove the valve body before I drop the trans; or at least loosen the ten bolts and that will drain the converter about 2/3. Before you remove the front bolts that hold the pump in, pull in and out on the input shaft and get some idea of how much it moves in and out. It would probably be easier to not remove the vb completely until the trans is out; cuz the park rod can sometimes be stubborn...all whilst fluid is dripping down your arms..
 
CudaFactHackJob said:
Yes. Then remove the valve body. Have you done that before? Nothing to watch out for there except a spring or blocker rod might come out of the accumulator. Just take it down slow and you'll see how it goes back in. I always like to remove the valve body before I drop the trans; or at least loosen the ten bolts and that will drain the converter about 2/3. Before you remove the front bolts that hold the pump in, pull in and out on the input shaft and get some idea of how much it moves in and out. It would probably be easier to not remove the vb completely until the trans is out; cuz the park rod can sometimes be stubborn...all whilst fluid is dripping down your arms..
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Use to getting dirty all the way up to my arm pits and beyond. lol;
 
Now how am I gonna get that picture out of my head?? But seriously, there are over a hundred guys on here that can talk you thru this procedure. Don't forget...WE LOVE PICS!!
 
CudaFactHackJob said:
Now how am I gonna get that picture out of my head?? But seriously, there are over a hundred guys on here that can talk you thru this procedure. Don't forget...WE LOVE PICS!!
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Will do the pics and thanks for the help I'm a bodyman not a mechanic but I guess we all learn one trade or another.
 
20200710_135748.jpg
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My ride and just finished it when I screwed up the tranny.
 
kursplat said:
sucks. at least you got some driving in while the weather was good
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I did and just finished it and it breaks down but my fault and I think we all have been there at least once. lol
 
AJ/FormS said:
I put dozens and dozens of hours into mine, before it stopped breaking parts. And I only have a 367/A833
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AJ glad to here from you yea if it can break I'll be the one to break it. lol
 
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