940 rebuild... should I?

[Dave Haertel]

Ok, so I've seen posts here that have said a 940 is one of the easiest transmissions to rebuild. Not sure how 'easy' it really is. I'm fairly mechanically adept, have been able to do most things to my car with the exception of the transmission and rear end work. My 71 Dart 340 Swinger is my daily and the current 940 will shift up ok but won't kick down on throttle stomp and I basically have to stop for it to come back down to 1st or second. During normal acceleration, 1-2 is at 20ish, 2-3 is at 40ish.

I've recently purchased a known to be good working 940 for a really affordable price. It was working fine, previous owner just swapped to a manual A833.

My options are: a) Take it to a shop, have them bench build it, swap it and roll. Pros/Cons: I learn nothing but have a dependable (hopefully) car. b) swap it now and try and tackle the rebuild of my existing 904 on my bench and then swap it back in. Pros/Cons: if the new transmission fails before I finish, I could be left out to dry with my daily for a time while I scramble. This seems unlikely though but it is something to consider. I guess it's also a drawback that I'm swapping this transmission twice.

I don't scare easily but there are SO many moving parts in a transmission I'm still just a touch apprehensive. Obviously I'd be doing all the research I can ahead of time and getting the best available rebuild manual but still. Can anyone who's actually rebuilt one let me know what they think?

Car: 340, mild cam (unknown - was built when I purchased the car), stock heads, weiand performance intake, new holly 650, new fuel pump, gas tank, lines, and HEI distributor. Rear end also unknown.

Thanks in advance.

 

[dukeboy440]

Ok, so I've seen posts here that have said a 940 is one of the easiest transmissions to rebuild. Not sure how 'easy' it really is. I'm fairly mechanically adept, have been able to do most things to my car with the exception of the transmission and rear end work. My 71 Dart 340 Swinger is my daily and the current 940 will shift up ok but won't kick down on throttle stomp and I basically have to stop for it to come back down to 1st or second. During normal acceleration, 1-2 is at 20ish, 2-3 is at 40ish.

I've recently purchased a known to be good working 940 for a really affordable price. It was working fine, previous owner just swapped to a manual A833.

My options are: a) Take it to a shop, have them bench build it, swap it and roll. Pros/Cons: I learn nothing but have a dependable (hopefully) car. b) swap it now and try and tackle the rebuild of my existing 904 on my bench and then swap it back in. Pros/Cons: if the new transmission fails before I finish, I could be left out to dry with my daily for a time while I scramble. This seems unlikely though but it is something to consider. I guess it's also a drawback that I'm swapping this transmission twice.

I don't scare easily but there are SO many moving parts in a transmission I'm still just a touch apprehensive. Obviously I'd be doing all the research I can ahead of time and getting the best available rebuild manual but still. Can anyone who's actually rebuilt one let me know what they think?

Car: 340, mild cam (unknown - was built when I purchased the car), stock heads, weiand performance intake, new holly 650, new fuel pump, gas tank, lines, and HEI distributor. Rear end also unknown.

Thanks in advance.

Its very straight forward. I have done it and am currently working on a push button 727. My advice, buy the below linked book. Follow it and you'll be just fine. Hardest part for me is the snap ring that holds the tail shaft on.

Chrysler TorqueFlite A-904 & A-727 Transmissions: How to Rebuild (Workbench How-to) by Hand, Tom: CarTech 9781613253359 Paperback - Buyback Express

This one is also nice to have

https://www.amazon.com/dp/1557883998/?tag=joeychgo-20

 

[Dave Haertel]

Its very straight forward. I have done it and am currently working on a push button 727. My advice, buy the below linked book. Follow it and you'll be just fine. Hardest part for me is the snap ring that holds the tail shaft on.

Chrysler TorqueFlite A-904 & A-727 Transmissions: How to Rebuild (Workbench How-to) by Hand, Tom: CarTech 9781613253359 Paperback - Buyback Express

This one is also nice to have

https://www.amazon.com/dp/1557883998/?tag=joeychgo-20

Thanks, any recommendations on rebuild kits? Torque Converter? Is a 2500 pretty standard for a mild performance build?

 

[Dubob]

Ok, so I've seen posts here that have said a 940 is one of the easiest transmissions to rebuild. Not sure how 'easy' it really is. I'm fairly mechanically adept, have been able to do most things to my car with the exception of the transmission and rear end work. My 71 Dart 340 Swinger is my daily and the current 940 will shift up ok but won't kick down on throttle stomp and I basically have to stop for it to come back down to 1st or second. During normal acceleration, 1-2 is at 20ish, 2-3 is at 40ish.

This sounds to me like it’s got a TV (kick down) linkage problem. I’d go over my linkage to ensure it’s operating as it should. Could be binding or just simply not adjusted correctly. Why spend money when you could end up with it doing the same thing after rebuild due to another issue.

 

[Dave Haertel]

This sounds to me like it’s got a TV (kick down) linkage problem. I’d go over my linkage to ensure it’s operating as it should. Could be binding or just simply not adjusted correctly. Why spend money when you could end up with it doing the same thing after rebuild due to another issue.

I've actually spent a ton of time on this (the kickdown linkage), unfortunately I think it's something in the valve body or up further. I put a new lokar cable linkage in and adjusted the hell out of it and I'm still at the this point unfortunately, it never got any better than this. I got 1 kick down out of it in the several months of fine tuning it.

 

[dukeboy440]

Thanks, any recommendations on rebuild kits? Torque Converter? Is a 2500 pretty standard for a mild performance build?

really need to find out what cam is in it to be precise for TQ converter.

 

[Dave Haertel]

really need to find out what cam is in it to be precise for TQ converter.

Is there a way to do so without pulling the motor? Or would the existing converter be able to be identified? This is my daily so I'd rather not be into pulling a motor to pull the cam on it.

 

[dukeboy440]

Is there a way to do so without pulling the motor? Or would the existing converter be able to be identified? This is my daily so I'd rather not be into pulling a motor to pull the cam on it.

you can do it without yanking the motor, the cam that is, probably need to remove the radiator and such for room as you'd have to pull the whole front acc drive, intake, distributor and timing cover. Other option is to simply pull the valve covers, get a micrometer and measure the lift at the valves and get a very close idea as to what the lift is, which would help with the TQ. As far as finding out what converter is in it, you'd have to pull the transmission out. Which you're gonna have to do regardless when you rebuild it.

 

[Dave Haertel]

you can do it without yanking the motor, the cam that is, probably need to remove the radiator and such for room as you'd have to pull the whole front acc drive, intake, distributor and timing cover. Other option is to simply pull the valve covers, get a micrometer and measure the lift at the valves and get a very close idea as to what the lift is, which would help with the TQ. As far as finding out what converter is in it, you'd have to pull the transmission out. Which you're gonna have to do regardless when you rebuild it.

I think replacing it with the same spec TQ would probably be ok if I can figure that out when I pull it, as I really don't think the TQ is part of the problem.

 

[j par]

Yes the transmission is extremely easy to rebuild even for a first-timer. You need to stop that boogeyman stuff in your head and realize this is just a simple little project. After you take the pan and the screen off the valve body comes off with 10 bolts and you have three accumulators which are just three Pistons with rings on them. Once you pull the front pump off, there's just two drums and a cluster gear inside. All the books will tell you not to forget to put the washer in between them! That's the big deal? Really? When you're done likely your intelligence will be completely insulted like mine was. Then you won't be asking any questions about what you think is going wrong with your transmission especially if you buy a nice shift kit along with the rebuild kit. I think I was into my transmission like a hundred and four for the rebuild kit and 92 for the stage 3 transgo shift kit. That transmission by far was the best one I've ever had in my life well except for my 4-speed! LOL
When I called Aamco and they said drive it in and drive it out for 1800 and then I called the shop and they said drop it on our bench and pick it up off of our bench for 800 I went to the parts store and bought the rebuild kit for 104. And never regret a moment of it since and will never let anybody ever rebuild my Transmissions ever again.

 

[Dave Haertel]

Yes the transmission is extremely easy to rebuild even for a first-timer. You need to stop that boogeyman stuff in your head and realize this is just a simple little project. After you take the pan and the screen off the valve body comes off with 10 bolts and you have three accumulators which are just three Pistons with rings on them. Once you pull the front pump off, there's just two drums and a cluster gear inside. All the books will tell you not to forget to put the washer in between them! That's the big deal? Really? When you're done likely your intelligence will be completely insulted like mine was. Then you won't be asking any questions about what you think is going wrong with your transmission especially if you buy a nice shift kit along with the rebuild kit. I think I was into my transmission like a hundred and four for the rebuild kit and 92 for the stage 3 transgo shift kit. That transmission by far was the best one I've ever had in my life well except for my 4-speed! LOL
When I called Aamco and they said drive it in and drive it out for 1800 and then I called the shop and they said drop it on our bench and pick it up off of our bench for 800 I went to the parts store and bought the rebuild kit for 104. And never regret a moment of it since and will never let anybody ever rebuild my Transmissions ever again.

Alrighty then!! That's what I was hoping to hear.

 

[j par]

Please remember what one of our great members here said in private to me. If one of my guys couldn't build two to three of those 904 a day he wouldn't be working in my shop for very long. With that said hobbyist should be able to do it in a week you would think, taking their time.

 

[j par]

I think by the time I had it apart I realized how easy it would be to put it back and was scratching my head. Now mind you I was smart enough not to pull that sprag out of the bottom of that case. That may give you a little challenge. But definitely nothing insurmountable I'm positive.

 

[Dave Haertel]

Please remember what one of our great members here said in private to me. If one of my guys couldn't build two to three of those 904 a day he wouldn't be working in my shop for very long. With that said hobbyist should be able to do it in a week you would think, taking their time.

Excellent. I can build computers all day long, and there's a few moving parts there, so I guess as long as I take it all apart in order and put it back in order the same way with the aid of books and the occasional YouTube video, I really should be able to do this.

 

[j par]

Excellent. I can build computers all day long, and there's a few moving parts there, so I guess as long as I take it all apart in order and put it back in order the same way with the aid of books and the occasional YouTube video, I really should be able to do this.

I took pictures and bagging stuff up and label them but actually when I was putting it back together I was kind of laughing thinking that really these things can't go in any other space then where they go. But take every precaution you'll be fine.

 

[RustyRatRod]

Them 940s are about as easy to build as them 277s.

 

[MoparMike1974]

"Them 940s are about as easy to build as them 277s."
Yes but the 747's are more complex.
Boeing 747 - Wikipedia

Seriously though, the 904 and 727 are by far some of the easiest transmissions to rebuild. Only thing simpler would be a powerglide.

 

[Dave Haertel]

"Them 940s are about as easy to build as them 277s."
Yes but the 747's are more complex.
Boeing 747 - Wikipedia

Seriously though, the 904 and 727 are by far some of the easiest transmissions to rebuild. Only thing simpler would be a powerglide.

I think I'm resigned then to giving this a shot on my own then. It does appear that most agree with the fact that there's a high probability of me being able to do this without trashing it, so I'm game. Now I just have to find the right rebuild kit and shift kit.

 

[TrailBeast]

This sounds to me like it’s got a TV (kick down) linkage problem. I’d go over my linkage to ensure it’s operating as it should. Could be binding or just simply not adjusted correctly. Why spend money when you could end up with it doing the same thing after rebuild due to another issue.

Might just need a part throttle kickdown kit, as it solved that problem with my old 904.
After installing that it would kick down with just about 2/3 throttle. (doing 45 and stand on it)

I think by the time I had it apart I realized how easy it would be to put it back and was scratching my head. Now mind you I was smart enough not to pull that sprag out of the bottom of that case. That may give you a little challenge. But definitely nothing insurmountable I'm positive.

If a guy couldn't put that sprag springs and rollers back in 2 min or less he wouldn't,,,, well you know.

One of the ends of the springs against the metal stops makes the spring curve away from the sprag center hub and the other end doesn't. (and is wrong)

 

[Dave Haertel]

Might just need a part throttle kickdown kit, as it solved that problem with my old 904.
After installing that it would kick down with just about 2/3 throttle. (doing 45 and stand on it)



If a guy couldn't put that sprag springs and rollers back in 2 min or less he wouldn't,,,, well you know.

Your adjustment recommendations actually got me to where it is now TrailBeast from another thread (they actually took off the TV linkage completely before I bought the car and I didn't recognize it), but I just couldn't get it any better and it would only go up well, it never was able to come down the way it should, basically it had to be down around 10 or lower to come down into 2nd and just about a full stop before going to 1st.

 

[TrailBeast]

Your adjustment recommendations actually got me to where it is now TrailBeast from another thread (they actually took off the TV linkage completely before I bought the car and I didn't recognize it), but I just couldn't get it any better and it would only go up well, it never was able to come down the way it should, basically it had to be down around 10 or lower to come down into 2nd and just about a full stop before going to 1st.

That's the way mine was before the kit.

 

[Dave Haertel]

That's the way mine was before the kit.

So, basically I'd be just replacing the valve body? Do you remember where you bought it? Am I just searching for the valve body part#?

 

[j par]

So, basically I'd be just replacing the valve body? Do you remember where you bought it? Am I just searching for the valve body part#?

I definitely agree to try and fix what you have but also highly encourage you to rebuild your spare.

 

[j par]

I think I'm resigned then to giving this a shot on my own then. It does appear that most agree with the fact that there's a high probability of me being able to do this without trashing it, so I'm game. Now I just have to find the right rebuild kit and shift kit.

Oh yeah my top tip for buying these kits is buy one if possible at a local transmission supplier. These kits are put together but likely underpaid warehouse workers. So sometimes they can put the wrong seal in or something like that cuz there's quite a few of them. But really that's all you're changing is a lot of the seals and stuff like that. Anyways instead of having to mail back and forth and describe to somebody over the phone your problems it's really nice to be able to walk in there and slap the wrong seal on the counter and let them go through there extras and find the one that you need. Or in my case they shorted me one clutch disc and another trip was the wrong rear main seal.

 

[TrailBeast]

So, basically I'd be just replacing the valve body? Do you remember where you bought it? Am I just searching for the valve body part#?

Not sure it actually had a part number, but it is called "Part Throttle Kickdown Kit".
Got it on Pat Blaise Ebay page and it is an add on to your valve body and works for 904 and 727 both.
You take the VB down and screw the part onto your existing valve body.

Looks like their store is closed until 06/08 but says he can be called.
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