727 Torqueflight transmission problems help

[charger2fast4u]

hey i have a 727 Torqueflight transmission in my 73 challenger. i was driving it the other day was shifting fine no problems and then i stoped at a stop sign. as i pulled out it was ok then it rode first gear out more then normal. but then shifted i got to a turn down the road and hammered it the RPM's shot up but no acceleration trans started slipping i got it to the next stop sign and then it wouldnt go anywhere tried reverse drive 1 2 nothing just shot the RPM's up so i towed it home started it and it drove normal but after about a minute it did the same thing what could be causing this to do that? i tried it again the next day and its fine for a minute then it slips and then i loose all gears. any help is appreciated

[Sublime/Sixpack]

How long has it been since you serviced the transmission? I'm thinking that your filter is clogged.

[green69rt]

First check fluid.
Has the trans been worked on lately??  Maybe it was put back together wrong. 
Next look at linkages.  I don't know if this uses cables or rigid linkage but check the adjustment points.  As the car warms it may be slipping the adjustment.
Drop the pan and check the filter and pickup.
If nothing then, unless you know how to work on an automatic, you're stuck taking it to a mecahnic.

Does anyone know if this trans still used the old bands that required adjustment?

[charger2fast4u]

i couldn't tell you the last time it was changed i just bought it 5 days before it happened. i dropped the pan and found a layer of dirt across the pan and filter i hope this is the problem. i'm going to get oil and a filter whats a good oil to go with? i'm going to buy acouple of bottles and filters so i can flush it out acouple times. while i'm doing that is there any other parts in there i should take out and clean? thanks

[Sublime/Sixpack]

Personally I'd clean out the pan, install a new filter, put the pan on with a new gasket, add ATF and see if it operates normally. If it does, well you're good to go, if not then go to plan B.

[charger2fast4u]

would it be good to use any type of auto transmission fluid? or does it need a certain type? i'd like to buy some cheap oil and flush out the trans then refill it with good oil. is there  anything else i should replace or clean in the trans besides the pan and filter? i hope this will fix it and i didnt cause internal damage.

[FLG]

Any name brand ATF fluid will do just fine.

[green69rt]

would it be good to use any type of auto transmission fluid? or does it need a certain type? i'd like to buy some cheap oil and flush out the trans then refill it with good oil. is there  anything else i should replace or clean in the trans besides the pan and filter? i hope this will fix it and i didnt cause internal damage.

I would guess the difference between cheap and good is not worth worring about.  It's been a long time but it seems like there are only about 7 quarts of fluid in a change.  Don't forget that you need to drain the torque converter.  Are you willing to save $2.00 on a $1000 transmission rebuild??  I get caught up in the same train of thought.  Don't let it overcome you sense of how to do things right!!

Yes, the type is important!  Follow you manual.  I just looked in  mine and it says use ATF type.  I know this sounds obvious but there is ATF and then there is Dextron and others.  Use the ATF.   

[charger2fast4u]

so i should stay away from dextron? i don't have a manual for it so i don't know what they suggest. to drain the torque convertor would i just take off a trans line from the radiator and let the car run while its draining then pour trans fluid in at the same time? sorry i don't know much about transmissions thanks for the help

[Ghoste]

What you are seeing in the manual as ATF stands for Automatic Transmission Fluid.  Don't confuse that with the Type F fluid that was typically used in Ford transmissions, from the factory your 69 Charger was equipped with a Dexron type fluid.  You can use either one with no ill effects it is more that you need to use one or the other and don't mix them back and forth.  I don't even know that is a for sure and not just a long held misconception but there is no harm in following it.  (I am talking about the mixing of the two types there not the part about a Dexron style from the factory in 69)

[b5blue]

AND before you change the motor oil check out the "warning if you run a flat tappet cam read this" topic!!!! 

[green69rt]

so i should stay away from dextron? i don't have a manual for it so i don't know what they suggest. to drain the torque convertor would i just take off a trans line from the radiator and let the car run while its draining then pour trans fluid in at the same time? sorry i don't know much about transmissions thanks for the help

To drain the trans, you have to drop the pan and let it run out, a big mess.  Stock pans don't have a drain plug.  One good reason to buy an aftermarket pan, they come with drain plugs plus they usually hold more fluid and run cooler.

To drain the torque converter, remove the dust shield from the front of the transmission (a flat piece of sheet metal that bolts to the front of the bell housing).  Look inside and you will see the torque converter with the starter ring gear on the outer edge.  Rotate the converter till you see the drain plug.  You'll probbaly have to use the starter to rotate the converter, it is bolted to the crankshaft!  Drain, replace the plug, put a new filter, gasket in the pan and bolt it back up and fill through the filler neck.  Hopefully back in business.

[b5blue]

AND ya want to check the fluid after you start it and with your foot on the brake run it through all the gears idling a few times. Final check fluid level (with the car sitting level) at full temp. Good Luck!

[green69rt]

What you are seeing in the manual as ATF stands for Automatic Transmission Fluid.  Don't confuse that with the Type F fluid that was typically used in Ford transmissions, from the factory your 69 Charger was equipped with a Dexron type fluid.  You can use either one with no ill effects it is more that you need to use one or the other and don't mix them back and forth.  I don't even know that is a for sure and not just a long held misconception but there is no harm in following it.  (I am talking about the mixing of the two types there not the part about a Dexron style from the factory in 69)

Yeap, just read the manual during the day when I wasn't so tired.  Here's what my Charger manual says.
" Replenish as necessary with automatic transmission fluid.  Use only fluids of the type labeled Dexron 'Automatic Transmission Fluid or Chrysler Automatic Transmission Fluid AQ-ATF-2848A or 2351A'....."

[TexasStroker]

Well hopefully getting everything flushed out will take care of the impediment.  This is the easiest thing for you to do on your own and could potentially cure the issue-hard for a trans to function with a blocked filter, lol.  I'd really consider popping for a finned, deep, cast aluminum pan with a drain plug.  They seal great, hold more fluid, and should drop the temp a little.  If that is out of budget, consider installing a magnetic drain plug just to save you hassle and a mess should you have to get back into the tranny.

You can probably adjust a few things as well.  Might check the throttle cable, kickdown linkage etc as suggested while you are servicing the car.

[Sublime/Sixpack]

Don't be surprised if your torque convertor doesn't have a drain plug, none of my Mopars or even my spare Mopar 727's or 904's have a drain plug on their convertors.

P.S. Old mopars like Type F ATF.

[John_Kunkel]

You can use either one with no ill effects it is more that you need to use one or the other and don't mix them back and forth.  I don't even know that is a for sure and not just a long held misconception but there is no harm in following it. 

My personal favorite brew for the 727 is a 50/50 mix of Dexron and type F. I'd like to see any credible proof that mixing types has any detrimental effects.

If the '73 converter is original it will have a drain plug, the drain plug didn't start to disappear until '77.

[Sublime/Sixpack]

I've read enough of your posts John to know that you know your stuff, but I am curious as to why you prefer a mixture of the two types of ATF. Care to share your thoughts on it?

[flyinlow]

Using type F in a torqueflight is an old school way to make it shift firmer.  Ford fluid feels grittier than dextron ( anything ford is gritty) and seams to make the clutches and bands grab harder.

Dextron is what they use in a 727 TF .  I have used type F  automatic transmission fluid with out any problems.

If you drain the converter it does take awhile idling to refill. will not refill in park.

[Ghoste]

You can use either one with no ill effects it is more that you need to use one or the other and don't mix them back and forth.  I don't even know that is a for sure and not just a long held misconception but there is no harm in following it. 

My personal favorite brew for the 727 is a 50/50 mix of Dexron and type F. I'd like to see any credible proof that mixing types has any detrimental effects.

I've never seen any either John which is why I wondered if it wasn't just a long held myth although admittedly I've never heard of anyone using a 50/50 mixture either.  I'm also curious as to why you like a mix of the two?

[John_Kunkel]

Type F has a more aggresssive coefficient of friction, this makes for firmer shifting but at the expense of some lubricating properties; the idea of mixing in Dexron is to increase the lubricating properties. Some guys even throw in a quart or two of synthetic 10-30 engine oil to a load of type F for the same reason.

In reality, no harm will come from mixing types, Mopar even states that the newer ATF+4 is backwards compatible with all previously recommended fluids. (Dexron, 7176, +2, +3)

[Sublime/Sixpack]

For years I've been using only Type F in my Bee, maybe next fluid change I'll try a mixture.

[charger2fast4u]

i replaced the filter and flushed out the system today drove it around lightly and it ran good for 15 minutes. i went home and checked over everything. then i went back out and after another 15 minutes of driving 3rd gear would slip real bad unless your almost idling then it grabs but 1st and 2nd are solid grabbing good. any suggestions or is it internal failure?

[flyinlow]

Sounds like a problem with the direct clutch. 3rd gear engages both clutches, no bands.

Not sure about  why  it is temp. sensative.  Any chance a cooler line is kinked shut?

[John_Kunkel]

Fluid thins out when it's warm so any leakage at the clutch sealing rings or seals will show up after the fluid is warm.

If the problem is hardened/shrunk seals an additive like Lucas or trans-X will often soften the seals enough to get more miles out of the unit. The only other alternative is remove/overhaul.

[charger2fast4u]

thanks for all the information and suggestions everyone. now that i know it is internally damaged i decided to order a keisler tko600 and swap in. should be here in 2 weeks  i figured if i got to spend the money on a rebuild i mise well go with what i wanted to do from the day i got the car. just didn't expect to be doing it so soon and under the circumstances of breaking it. i'm sure i will have some questions on the installation so i will make a new thread when i get it.

[jsfury]

Hello my fellow MoPar heads. I have a transmission problem that has got me stumped and I was wondering if any of you out there might be able to help me. Last march I blew the 727 automatic trans. in my '75 Dodge D200. I have had in my mechanics garage for the last three days replacing the blown one with another 727 I had saved out of my '73 Plymouth that was working when I removed it from that car.

My problem is it won't shift out of first gear. If anyone can help me with this so I can get my truck back on the road it would be greatly appreciated. The two questions I have regarding this problem is; A.) Why will it not shift from first to second and up, and B.) is this something that will be hard to correct?  What actually makes these 727's shift? There's no modulator valves on them like the '70's GM trans.

Thank you again for any info you can provide me.

[John_Kunkel]

Welcome to the board.

First, be sure the TP (kickdown) linkage isn't the problem by disconnecting it at the transmission lever and allowing the lever to come full forward. If it still won't upshift, the problem is most likely in the governor; there is a governor test port in the tailhousing, a pressure gauge hooked to the port should show about 1 psi for each mph. If the pressure is low it won't upshift.