a727 no third gear

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Weak direct rings could cause a no third but still have good reverse. Reverse uses higher pressure. How's the endplay? Is the direct drum riding where it's supposed to? Excessive clutch clearance could contribute to it too. Are you sure there is no scoring inside the direct drum where the rings ride? Absolutely no ridges whatsoever? Or a worn direct drum bushing, or pump journal where it rides. Can you wobble the drum? A wobbly drum will wear out the sides of the rings and they will lose tension.
direct rings? are you talking about the snap ring or?
 
I think the problem might be in the direct ring area on the back of the pump. I'm not talking about the snap ring or even close to it. I'm talking about the TWO interlocking sealing rings on the back of the pump. They are a source of many problems on the 727. Everything in that area has to be perfect. I used to install special aluminum/teflon rings in that application..back when I was a perfectionist..
 
when I aircheck the clutches in the pump when sitting in a vise they seem to seal up really well, then when I put them in the tranny and aircheck I hear a lot of air coming from I think the front clutch, somewhere in that area
Well then u have ur answer. The inner seal on the front drum isn’t sealing very well if u hear hissing while using 30 psi. Check the valve body over real good or replace it as gas been mentioned. Kim
 
He's probably hearing a ring leak. When it sits on the pump; it's centered, but when it's in the trans, it falls off center.
 
I think the problem might be in the direct ring area on the back of the pump. I'm not talking about the snap ring or even close to it. I'm talking about the TWO interlocking sealing rings on the back of the pump. They are a source of many problems on the 727. Everything in that area has to be perfect. I used to install special aluminum/teflon rings in that application..back when I was a perfectionist..
ill forsure replace them
 
Well then u have ur answer. The inner seal on the front drum isn’t sealing very well if u hear hissing while using 30 psi. Check the valve body over real good or replace it as gas been mentioned. Kim
when I get home ill check it again, im thinking that's what it could be
 
They were probably already replaced. Like I said, check the inside of the drum where the rings ride, the drum bushing, and the journal on the pump where that bushing rides.
 
Somebody already put this together wrong, and you have to find their mistake.
ill check the journal and bushing, someone could've been in there , yesterday I talked to the guy I got the truck from and he said it was never rebuilt or touched when he had it, he said it went into all the gears and worked before he parked 10+ yrs ago... but that's what he says ...
 
Ok so, over the weekend I put new inner and outer seals on the pistons and steel rings on the pump stator, I airchecked everything, all was well, put it back together, still nothing, took the valvebody out and tore it down, cleaned it, through it back in, now 3rd gear works..lol still need to adjust kickdown linkage but overall works like it should..
 
Wataminit
You HAVE to know at least which clutch does what.
You said reverse is fine
This means the L/R band is applying so the L/R servo is just fine. But to make reverse the trans also applies the Direct clutch, which works in both Low and Third gear.
This means the Direct clutch is also working.
You said second gear works, so Both the Forward clutch and the 2ND servo is working.
As to hard parts; everything is working, there's nothing to test and you didn't need to take anything apart nor install the pressure gauges.
Just by knowing how is supposed to work you have narrowed the problem down to just the Valvebody.
Now, if you install a pressure gauge you can VERIFY what you already know. And so now, you can go to the root which has to be the VB, and I suspect the #3 ball is missing, or the wrong diameter one went in there. I think it's #3,lemme check. Hyup #3

So why does it still work in reverse? Because in reverse all pressure regulation stops and the pump puts full pressure into that circuit which can be more than 250 psi........ so if you put a pressure gauge on that circuit and didn't see 250 or at least something close to it, and you knew how it worked. well, then a big red flag would go up and you'd think hmmmmmmmmmmmmmm I wonder if the #3 ball is in there.
So then you would put the pressure gauge on third gear, and run it up to third gear where you should be seeing 55 to 90 depending on where you have the KD cranked to but instead you see IDK 10 psi. Bam! up goes another Red flag, cuz you know there should be 90ish in there just before it kicks down.

So because you know how it's supposed to work and the pressures are verifying that something is wrong; your're brain combines and says
hmmmmmmmmmmmmmmmm I wonder if I put the right ball in there or even if missed that cavity.
And then you remember the ball you found on the bench, after the trans was installed.......lol.
When the trans shifts into third, and the #3 ball is not in there, then the oil goes right on by the Direct clutch and dumps into the pan, at the manual valve. That's why MaMopar put the ball in there, to prevent that from happening.
But in reverse the fluid still goes by the Direct clutch but is blocked by the 2-3 shift valve, then it backs up and pressurizes the Direct clutch, anyhow.
So I would be very surprised to see that #3 ball in there.


However
if the #3 ball is in there, the same no third gear will occur if the 2-3 valve is stuck, or if the governor pressure is too low, but your pressure gauge would not have read so low in Direct.
See that's how the pressure gauge helps you diagnose, when you know how it's supposed to work.
Finally, the 2-3 shift spring could be wrong.
So now if the pressure is right in reverse and nothing AT ALL in direct, then you go to the the governor to see if it has enough pressure to command the 2-3 shift. and if yes then you have exactly two options left which amount to the same thing; either the valve is stuck, or the spring is too stiff. Well I suppose the regulated pressure could be too low or the line pressure too low, but then you would be having other shift problems which you didn't mention.
In any case, the trans can stay up, just the VB needs to be looked at.
That's my opinion, I could be wrong
 
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Wataminit
You HAVE to know at least which clutch does what.
You said reverse is fine
This means the L/R band is applying so the L/R servo is just fine. But to make reverse the trans also applies the Direct clutch, which works in both Low and Third gear.
This means the Direct clutch is also working.
You said second gear works, so Both the Forward clutch and the 2ND servo is working.
As to hard parts; everything is working, there's nothing to test and you didn't need to take anything apart nor install the pressure gauges.
Just by knowing how is supposed to work you have narrowed the problem down to just the Valvebody.
Now, if you install a pressure gauge you can VERIFY what you already know. And so now, you can go to the root which has to be the VB, and I suspect the #3 ball is missing, or the wrong diameter one went in there. I think it's #3,lemme check. Hyup #3

So why does it still work in reverse? Because in reverse all pressure regulation stops and the pump puts full pressure into that circuit which can be more than 250 psi........ so if you put a pressure gauge on that circuit and didn't see 250 or at least something close to it, and you knew how it worked. well, then a big red flag would go up and you'd think hmmmmmmmmmmmmmm I wonder if the #3 ball is in there.
So then you would put the pressure gauge on third gear, and run it up to third gear where you should be seeing 55 to 90 depending on where you have the KD cranked to but instead you see IDK 10 psi. Bam! up goes another Red flag, cuz you know there should be 90ish in there just before it kicks down.

So because you know how it's supposed to work and the pressures are verifying that something is wrong; your're brain combines and says
hmmmmmmmmmmmmmmmm I wonder if I put the right ball in there or even if missed that cavity.
And then you remember the ball you found on the bench, after the trans was installed.......lol.
When the trans shifts into third, and the #3 ball is not in there, then the oil goes right on by the Direct clutch and dumps into the pan, at the manual valve. That's why MaMopar put the ball in there, to prevent that from happening.
But in reverse the fluid still goes by the Direct clutch but is blocked by the 2-3 shift valve, then it backs up and pressurizes the Direct clutch, anyhow.
So I would be very surprised to see that #3 ball in there.


However
if the #3 ball is in there, the same no third gear will occur if the 2-3 valve is stuck, or if the governor pressure is too low, but your pressure gauge would not have read so low in Direct.
See that's how the pressure gauge helps you diagnose, when you know how it's supposed to work.
Finally, the 2-3 shift spring could be wrong.
So now if the pressure is right in reverse and nothing AT ALL in direct, then you go to the the governor to see if it has enough pressure to command the 2-3 shift. and if yes then you have exactly two options left which amount to the same thing; either the valve is stuck, or the spring is too stiff. Well I suppose the regulated pressure could be too low or the line pressure too low, but then you would be having other shift problems which you didn't mention.
In any case, the trans can stay up, just the VB needs to be looked at.
That's my opinion, I could be wrong
I appreciate your reply, ill actually keep this all in mind, there was some junk in the valve body where the check balls are, there were 6 check balls then a 7th one between the separator plate and the other half (idk what its called) but where you replace the filter for the VB, but I cleaned it and through it back together and it worked...lol
 
Wataminit
You HAVE to know at least which clutch does what.
You said reverse is fine
This means the L/R band is applying so the L/R servo is just fine. But to make reverse the trans also applies the Direct clutch, which works in both Low and Third gear.
This means the Direct clutch is also working.
You said second gear works, so Both the Forward clutch and the 2ND servo is working.
As to hard parts; everything is working, there's nothing to test and you didn't need to take anything apart nor install the pressure gauges.
Just by knowing how is supposed to work you have narrowed the problem down to just the Valvebody.
Now, if you install a pressure gauge you can VERIFY what you already know. And so now, you can go to the root which has to be the VB, and I suspect the #3 ball is missing, or the wrong diameter one went in there. I think it's #3,lemme check. Hyup #3

So why does it still work in reverse? Because in reverse all pressure regulation stops and the pump puts full pressure into that circuit which can be more than 250 psi........ so if you put a pressure gauge on that circuit and didn't see 250 or at least something close to it, and you knew how it worked. well, then a big red flag would go up and you'd think hmmmmmmmmmmmmmm I wonder if the #3 ball is in there.
So then you would put the pressure gauge on third gear, and run it up to third gear where you should be seeing 55 to 90 depending on where you have the KD cranked to but instead you see IDK 10 psi. Bam! up goes another Red flag, cuz you know there should be 90ish in there just before it kicks down.

So because you know how it's supposed to work and the pressures are verifying that something is wrong; your're brain combines and says
hmmmmmmmmmmmmmmmm I wonder if I put the right ball in there or even if missed that cavity.
And then you remember the ball you found on the bench, after the trans was installed.......lol.
When the trans shifts into third, and the #3 ball is not in there, then the oil goes right on by the Direct clutch and dumps into the pan, at the manual valve. That's why MaMopar put the ball in there, to prevent that from happening.
But in reverse the fluid still goes by the Direct clutch but is blocked by the 2-3 shift valve, then it backs up and pressurizes the Direct clutch, anyhow.
So I would be very surprised to see that #3 ball in there.


However
if the #3 ball is in there, the same no third gear will occur if the 2-3 valve is stuck, or if the governor pressure is too low, but your pressure gauge would not have read so low in Direct.
See that's how the pressure gauge helps you diagnose, when you know how it's supposed to work.
Finally, the 2-3 shift spring could be wrong.
So now if the pressure is right in reverse and nothing AT ALL in direct, then you go to the the governor to see if it has enough pressure to command the 2-3 shift. and if yes then you have exactly two options left which amount to the same thing; either the valve is stuck, or the spring is too stiff. Well I suppose the regulated pressure could be too low or the line pressure too low, but then you would be having other shift problems which you didn't mention.
In any case, the trans can stay up, just the VB needs to be looked at.
That's my opinion, I could be wrong

Thanks for all that info. Damn, how do you keep it all straight??? Working on a couple of 727 rebuilds now, so this is all real good readin'.
Cheers! Glad the OP has gotten it all working!
 
I could be wrong; I'm waiting for someone to agree, or not....... it's been more than 25 years since I had a VB apart.
5 of .25 plus one 3/8ball is correct, but some years had 3 different sizes.
I have never seen a ball in the lower half, but I have also never worked on an 84 D-100
IIRC the older ones had a 3/8 convertor check ball back in the 60s.
By the early 70s,I think, the 3/8 convertor check was gone,
But I remember finding some VBs with just one 11/32..I Don't recall what year(s) it might have been used, but if you pay attention, you will see the slightly larger cavity. IIRC that cavity was right beside a regular sized cavity.If you put a 3/8 in there you will not get high gear.
Ok I looked it up and 69 to 72 at least,had that 11/32 ball, you can't miss it; the cavity is obviously larger.

I have also recorded a few springs dimension over the years. As to the 2-3 spring, I have recorded ;
.625d x 1.0 long, natural color, 6.5 coils of .045 wire

BTW; if your KD mechanism is springy as it should be,and the lever is wired all the way back., then when in second gear,that lever is commanding the trans to stay in second a really long time. With tall tires and 3.23s, this could be 80 mph, or even more.
BTW: there are two .325 springs in the VB, of similar length
The KD I have recorded .325 x 1.275long,13 coils of .054 wire
and ; the TC regulator is .325 x 1.24 long,12.75 coils/.045 wire
I'm sorta remembering that the rooster comb detent spring is of similar size as well, but I didn't record it cuz as I recall , it was quite a bit stiffer and obvious to me where it went.
Ok I found a 6th 1/4"ball in 78 and up, right smack-dab in the center of the upper half ;

still nothing about a ball in the lower half.
 
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I could be wrong; I'm waiting for someone to agree, or not....... it's been more than 25 years since I had a VB apart.
5 of .25 plus one 3/8ball is correct, but some years had 3 different sizes.
I have never seen a ball in the lower half, but I have also never worked on an 84 D-100
IIRC the older ones had a 3/8 convertor check ball back in the 60s.
By the early 70s,I think, the 3/8 convertor check was gone,
But I remember finding some VBs with just one 11/32..I Don't recall what year(s) it might have been used, but if you pay attention, you will see the slightly larger cavity. IIRC that cavity was right beside a regular sized cavity.If you put a 3/8 in there you will not get high gear.
Ok I looked it up and 69 to 72 at least,had that 11/32 ball, you can't miss it; the cavity is obviously larger.

I have also recorded a few springs dimension over the years. As to the 2-3 spring, I have recorded ;
.625d x 1.0 long, natural color, 6.5 coils of .045 wire

BTW; if your KD mechanism is springy as it should be,and the lever is wired all the way back., then when in second gear,that lever is commanding the trans to stay in second a really long time. With tall tires and 3.23s, this could be 80 mph, or even more.
BTW: there are two .325 springs in the VB, of similar length
The KD I have recorded .325 x 1.275long,13 coils of .054 wire
and ; the TC regulator is .325 x 1.24 long,12.75 coils/.045 wire
I'm sorta remembering that the rooster comb detent spring is of similar size as well, but I didn't record it cuz as I recall , it was quite a bit stiffer and obvious to me where it went.
Ok I found a 6th 1/4"ball in 78 and up, right smack-dab in the center of the upper half ;

still nothing about a ball in the lower half.
FYI the truck is a 75 d 100 ..lol tbh I didn't measure any of the check balls, I did notice 5 where the same size and 1 big one IN the valvebody its self, I didn't even bother the 7th one I found in the lower half, Ive taken other earlier valvebodies apart from 904's and have seen differences but most of them had the 5 smaller check balls and the 1 big 1... and of course the rooster comb ball ...lol
 
Oh crap; well,as for A727s, I've only done a few of those;
As for A904s, I've done about everything from 1967 to 1980;
and I cannot recall ever seeing a ball in any lower half.
However, I seem to remember seeing a lower half that appeared to have a ball-cavity up near the accumulator area, but not a ball in it. Not sure. In any case It doesn't show up in any reference materials I got
 
Oh crap; well,as for A727s, I've only done a few of those;
As for A904s, I've done about everything from 1967 to 1980;
and I cannot recall ever seeing a ball in any lower half.
However, I seem to remember seeing a lower half that appeared to have a ball-cavity up near the accumulator area, but not a ball in it. Not sure. In any case It doesn't show up in any reference materials I got
I really wish I would've taken a photo but I didn't, the ball sat near where the little tiny filter fits in, not the filter that faces the pan...lo..But the ball was there so ...idk hahaha
 
Here

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68DC4C4D-C1FC-4F37-B2F4-809638B3B784.jpeg


EF9CD24B-FFEA-46CC-A5A9-94C819DE4084.jpeg


12737021-A0D0-468E-ABAB-E5EC443D925D.jpeg
 
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