727 Tranny Problems I Think

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hoosierdaddy

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OK I installed a 727 tranny in my Duster that was suppose to good . I filled the tranny a few days ago and moved the car from the lift into the driveway no issues . I decided to do a shake down run around the block last night and the car wouldn't hardly move , I let it warm up a bit more and got to move in reverse back into the garage . I searched my problem on FABO and found the seals are probably hard and in need of a rebuild . So I ran home today at lunch , started the car and it firmly went into R & D(cold) . I come home tonight and raise the rear wheels off the ground and again the car goes into gear firmly and seems to have no problem . The reason I raised the rear wheels up I had the idea of trying make it shift but in reality it seemed like a bad idea . I'm just wondering if anyone has had this issue on a freshly filled tranny and yes it is filled to the proper level .
 
OK I installed a 727 tranny in my Duster that was suppose to good . I filled the tranny a few days ago and moved the car from the lift into the driveway no issues . I decided to do a shake down run around the block last night and the car wouldn't hardly move , I let it warm up a bit more and got to move in reverse back into the garage . I searched my problem on FABO and found the seals are probably hard and in need of a rebuild . So I ran home today at lunch , started the car and it firmly went into R & D(cold) . I come home tonight and raise the rear wheels off the ground and again the car goes into gear firmly and seems to have no problem . The reason I raised the rear wheels up I had the idea of trying make it shift but in reality it seemed like a bad idea . I'm just wondering if anyone has had this issue on a freshly filled tranny and yes it is filled to the proper level .

I never have, maybe the pump didn`t pick up like it should have / did u fill the convertor before installation ?
 
Well you probably know all about this. The Mopar automatics have this thing called Morning Sickness where the pump needs to fill the torque converter before you take off. Torque Converter drain back usually causes this. The so called proper way on a cold start is to start the engine, then shift it into Neutral (the pump starts pumping in Neurtal and not in Park) let the engine and trans warm up a bit. The torque converter is now full and you are good to go.

Some folks put a check valve in the outgoing side of the trans cooler line to the radiator to prevent the torque converter drain back. There is a kit from Trans Go that is supposed to help this drain back too.

And Yes as you probably know, check the fluid idling in Neutral and not Park on the old Mopars.

Hope this sheds some light on things for you . . .
 
Read the dipstick, CHECK IDLING HOT IN NEUTRAL . We can get the same symptom from a worn trans if the pan is full of debris. It'll wok perfect cold/initially then start to slip more and more as filter collects to clogged. I forget if that diagnosis tip was Ford, GM, Chrysler, or all. Good luck with it.
 
Read the dipstick, CHECK IDLING HOT IN NEUTRAL . We can get the same symptom from a worn trans if the pan is full of debris. It'll wok perfect cold/initially then start to slip more and more as filter collects to clogged. I forget if that diagnosis tip was Ford, GM, Chrysler, or all. Good luck with it.

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I ended up being a pint low . I've done a little more driveway testing and all seems good so road time is the plan for the weekend . Thanks to everyone
 
Do you have the tv (kickdown) linkage hooked up and properly adjusted?

Yes, pretty important too.

There is a good youtube video on how to do it, by the old mopar techs of the 60s if you can find the video.
Search: Mopar 727 kickdown adjust
Good stuff there . . .
 
I ended up being a pint low . I've done a little more driveway testing and all seems good so road time is the plan for the weekend . Thanks to everyone

It's also possible if that trans sat for awhile before it got put in something that the seals "took a set" and some warmup helped them flare back out and seal.
 
OK I'm back with a new problem , I went around the block and couldn't get the trans to shift out of 1st unless I did it manually and I never did get into 3rd . The trans I have was alledged to have been race prepped at one time , I did remove a mvb and install a known working automatic vb . I got into the governor last night and cleaned everything and reinstalled it but I didn't button up the tail shaft housing because I don't know if I have stock governor or race . I have a governor from a 904 thats different(appearance) from my 727 so I'm wondering if anyone can post a pic of a small block 727 governor . I realize this may tell me nothing but who knows .
 
Well...we started with a good transmission with the proper fluid level in the beginning of this thread and now we have a "race" prepped transmission with a manual valve body...Anything else we should know. Information is how you diagnose. Not guessing with partial info. George Jets was tactfully informing you how to properly check and fill the trans.
 
Do you have the tv (kickdown) linkage hooked up and properly adjusted?
Sorry I missed your post post but I'm not sure of anything at this point . I'm using a Lokar style KD cable and I made several adjustments that did nothing to help the shifting , thats why I suspect the governor . Hopefully the governor was sticking since it was a little dirty(burnished looking) when I removed it .
 
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Alright so I decided to take a big swing at the tranny since I've read and understand a tiny bit more . First off I reinstalled the original accumulator and MVB ,while I was in there I adjusted the front band . I took the car around the block and everything seems OK . When I was cleaning up my bench a ran across a rod about 3" long and it hit me it was a block rod for the accumulator which I didn't remember removing . So the next decision is whether to drain the tranny and install the rod or let it be .
 
Without a spring or blocker rod in there the acc slams back and forth. The rod blocks it from moving and makes the 2nd gear shift firmer. The spring will cushion the impact. U could use almost any spring that will fit. Years ago the instructions said to leave the spring out. I have done many without the springs and have had no ill effects. Kim
 
Without a spring or blocker rod in there the acc slams back and forth. The rod blocks it from moving and makes the 2nd gear shift firmer. The spring will cushion the impact. U could use almost any spring that will fit. Years ago the instructions said to leave the spring out. I have done many without the springs and have had no ill effects. Kim
I did install the spring so for now it works good and yes it shifts smooth into second .
 
If you had an engagement problem and cured it with just one pint of fluid, then it will probably rev between 2 and 3 at wot cuz it's still low.
 
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