i am replacing a rear servo in my 727 trans because it slips very bad in reverse. ..is there anything else i need to look at or do while the pan and valve body are out? reverse seems to be the only slippage i am having.any suggestions?
727 trans question
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hemi#1
Well-Known Member
check out your band torque specs. it's in inch pounds. adjust to factory specs. it may be loose I rebuilt my trans on my 65 satellite and it shifts like a new car there are 2 bands. one for first and reverse and the other one is 2nd. and 3rd. there are lock nuts on both of them they are outside the trans.
mopar 3 B
Well-Known Member
Do not know what TF you have but 1st and revers are usually in the trans case on the 727.
Assuming 3rd gear works fine I'd pull the valve body and air check the servo. If it moves back and forth it should be fine. Unless the seal is torn or the piston is cracked there should not be a problem with it. Make sure the band clamps down on the drum during air check as the band or pivot could be broken or the strut out of place. If all the tests pass my bet is a valve body issue.
Doug
Doug
Mopar-Charger
Well-Known Member
Seal is most likely torn like he said. When I rebuilt mine the servo and seal were in pieces. First gear barely worked, and it wouldn't even go into reverse. I have a TF Transmission book, I could pull it out and give you in detail how to swap it out. However I'm fairly sure You have to take off the bands to get to it. Again, i'll have to check the book and see. It's been a couple years.
Hope this helps narrow it down.
66Satellite47
Well-Known Member
Like dvw says check to see if the band applies. Loosen the lock nut on rear band adjuster, count the # of turns in until adjuster screw is snug. Should be 2 turns. Look to see if the band has worn out. I learned to rebuild TF's after losing reverse. The rear band had burned away completely ( from using low for engine braking tooo often). Actually cut the drum in half. Rear servo seal failure could also be the cause..
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Hemi Rebel
Well-Known Member
The best way to clean it is to completely disassemble it. I dont highly recommend this if you are a novice. As long as the fluid is not burnt or very dirty, just slip it in a plastic bad while you deal with the band.
Hemi Rebel
Well-Known Member
You could spray it off and hit it with compressed air.
i am thinking the band may be bad ,i cant see any kind of pad on it and the drum has some wear.first gear didnt slip that i could tell but it was obvious in reverse.. the first thing i tried to do was adjust the rear band but it would not snug up. i even had t o remove the lock nut and the bolt kept turning thats when i removed servo and saw the inner crack .but the seal and the part of the servo that the seal is attached looks ok.i guess i should have looked more at the band..if the band is bad im thinking that may mean the trans will have to come out...the drum has grooves in it also. i just got this car from a member and they offer no help. it was the hulk car that was for sale a few weeks ago.there was no mention of trans problems . i wont buy another car without driving it first.i had it transported from florida to tenn.
miller
Well-Known Member
If one band is bad (sounds like your's is flat wore out), and the drum is wore, they need to be replaced. Something else to remember is all that worn material has gotten into your fluid...and into the shift body. Doesn't take much, because of the close clearances, to mess up that body.
Overhauling a 727 is not that bad. And doing it yourself, you can get by fairly cheap, over paying someone a long-winded price. My last 727 complete overhaul cost me around $250-275...and that includes the $100 I paid for the tranny itself!
That one definately needs a complete.
Overhauling a 727 is not that bad. And doing it yourself, you can get by fairly cheap, over paying someone a long-winded price. My last 727 complete overhaul cost me around $250-275...and that includes the $100 I paid for the tranny itself!
That one definately needs a complete.
Hemi Rebel
Well-Known Member
Make sure the little strut didnt fall out. The band would need to be way stretched or broken for you to be able to run the adjustment bolt all the way in and not make a difference.
Either way, sounds like it needs to come out and apart. Stuff happens. Especially when you play with 50 year old cars. Its still a bad *** car you have. At least from what i can see in the pics. To be honest, if i had my choice of what drivetrain part would fail it would be the trans. I would rather deal with that than a wiped cam or bottom end issue in the motor. Or a blown up differential.
I know that doesnt make your situation suck any less, but it could be worse imho.
Either way, sounds like it needs to come out and apart. Stuff happens. Especially when you play with 50 year old cars. Its still a bad *** car you have. At least from what i can see in the pics. To be honest, if i had my choice of what drivetrain part would fail it would be the trans. I would rather deal with that than a wiped cam or bottom end issue in the motor. Or a blown up differential.
I know that doesnt make your situation suck any less, but it could be worse imho.
thanks very much miller and hemi rebel,the strut was in place i didnt see alot of trash in the fluid but there is some,looks like when the trans started giving trouble they decided to dump the car . i have another trans in a road runner with a stall and a reverse manual valve body that i want to take out but not sure how to make it work with the shifter in the hulk,i think its a after market hurst shifter. i have in the hulk. or i have a stock trans i could add a shift kit and check the bands and put my new servo in it..it did shift before but i never really ran it on the road much. sound like my best bet is to rebuild one and clean out the valve body..thanks alot for the info and positive outlook..i was hoping to take the hulk for a cruise and not have to work on it..but...at least the motor seems ok
mopar 3 B
Well-Known Member
If you take the valve body apart taking plenty of pictures of before and during disassembly can save lots of headaches when you put it back together. Have learnt the hard way not to trust the manufacture build date for rebuild of valve bodies they are to easily swapped from one trans to another.
miller
Well-Known Member
Even if you've got experiance overhauling those things...best bet is to get a good 727 reference/rebuild manual. It makes a world of difference. Last evil thought is, in any auto trans, there's plenty of parts and pieces that need to be looked at. Anything else is just a bandaid. If you build it yourself, at least you know what is what, and what kinda shape it's in.
Lol, but I'm world's worst, trusting anybody. Hell, I got two hands!
Lol, but I'm world's worst, trusting anybody. Hell, I got two hands!
66Satellite47
Well-Known Member
X 2 on Miller,
727's aren't that hard, but a little demonstration from someone with experience and a good manual (factory service manuals are great if you can figure out how to duplicate the "special tools"). FYI the rear band isn't "on" in 1st gear in Drive, only in 1 & reverse. My advice is not to screw with shift kits, that's why I learned how to rebuild Torkflites (burned up rear band, cut the rear drum in half, no reverse). Good luck
if i dont use a shift kit how will i get a quick shift from 1st to second and 2nd to third? 66sat are you saying the rear band isnt tight on drum in 1st gear? what makes reverse happen and what makes 1st happen? i looked for the info on u tube and google with no luck. i dont have to have the tires bark when shifting gears just need it to change gears without hesitation or slipping.i also noticed the kick down lever was wired back. i guess i want to be able to drive around town and go to the drag strip occasionally with the hulk car.any ideas how to use my trans that has a reverse valve body from another car? would i have to change out my shifter.i would be taking it out of a 71 rr that has a stock console shifter.i purchased the rr with the reverse valve body so not real familiar with it but it works and i am n ot planning to race the roadrunner so it would be a better trans for the hulk.just not figured out yet what to do about the shifter in the hulk car.
miller
Well-Known Member
Okay...IF a 727 is built RIGHT...and a minor adjustment is made on both band adjustments, that thing will shift as hard, and fast as you want it.
A bit of research. No, don't look for a Mopar trans manual. Don't see mine right now, but for 727s there is a manual that's highly recommended, written by a individual, and that book will tell you ANYTHING you ever wanted to know on 'em. Can't remember the book's name, but easy to look up.
If you have any intentions of touching a 727, get a copy of that manual. Lol, then all you gotta do is 'hold your mouth right', and go for it.
Somebody toss an old dog a bone...
A bit of research. No, don't look for a Mopar trans manual. Don't see mine right now, but for 727s there is a manual that's highly recommended, written by a individual, and that book will tell you ANYTHING you ever wanted to know on 'em. Can't remember the book's name, but easy to look up.
If you have any intentions of touching a 727, get a copy of that manual. Lol, then all you gotta do is 'hold your mouth right', and go for it.
Somebody toss an old dog a bone...
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