a727 no third gear

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Kody meile

Kody meile

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hello everyone, I got a 75 dodge d100 a week ago 318\727 combo, all stock, got t running really good, topped off tans fluid that was pretty much empty, went for a drive, no third gear, unhooked kickdown linkage, still no third gear, checked governor, isn't stuck, by the way reverse work so I know the front clutch is working, both bands adjusted like how there supposed to be, and I did aircheck the it, both clutches make a nice thud, I haven't a line or governor pressure test yet, I don't have a guage atm, ill get one asap, but I did look into the 2-3 shift valve, the plug was stuck, idk if that was the problem but i took it out along with the spring and valve, cleaned everything and put back in, moves freely now, anyadvice or ideas fron anyone? Oh and by the way....I did pull the trans out and pull it apart, all clutches , steels, rubber seals for pistion and inner lips were fine, startor looks good along with the sealing rings, it has steel ring on it, but anyways thanks for any replies
 
Make absolutely sure it full of fluid by checking in neutral.
Then I would pull the pan, check for debris.
Then pull the VB and air test it because it sounds like and internal seal or sealing ring leak if none of the above.
Also if 2nd has some sort of issue where it can't apply the band it can shift directly from 1st to 3rd, so be sure this isn't what it is doing by putting the trans in manual second.

An FYI, a plugged or incorrectly installed filter can cause a no 2-3 upshift also.
 
Well, if you found an issue in the valve body, I would think you are gonna go back there first! Maybe try a known good one and go from there. I would not be a bit surprised to find you have a fried rear clutch, even if it looked good before. Just because it sounds good does'nt mean theres any frictions left. BTW, where did all the fluid go?? If you are saying it leaked out whilst someone was driving the vehicle, well then there is damage done!
 
TrailBeast said:
Make absolutely sure it full of fluid by checking in neutral.
Then I would pull the pan, check for debris.
Then pull the VB and air test it because it sounds like and internal seal or sealing ring leak if none of the above.
Also if 2nd has some sort of issue where it can't apply the band it can shift directly from 1st to 3rd, so be sure this isn't what it is doing by putting the trans in manual second.

an FYI, a plugged or incorrectly installed filter can cause a no 2-3 upshift also.
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I forgot to mention that this truck was sitting for maybe 10-15yrs, wouldn't that cause the rubber seals to harden? they have to be soft to work right correct?
 
Lefty71 said:
Well, if you found an issue in the valve body, I would think you are gonna go back there first! Maybe try a known good one and go from there. I would not be a bit surprised to find you have a fried rear clutch, even if it looked good before. Just because it sounds good does'nt mean theres any frictions left. BTW, where did all the fluid go?? If you are saying it leaked out whilst someone was driving the vehicle, well then there is damage done!
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the truck saat for a long time 10 or 15 years not sure, but the trans was empty, all the clutches front and rear were practically brand-new, there was no friction material or any sort of debri and the filter didn't look nasty at all when I did drop the pan.
 
Well, we had a Frod that we threw an old trans that sat forever and never moved... The band popped loose off one end from rust in one spot on it's maiden voyage. Either way, it needs all new seals and rubbers after sitting that long, so it's gotta come apart. Also, there are micro line filters in two places on that unit., one at the gov. and the other in the valve body. I'd bet they plugged right up once you kicked up the rust inside.
 
TrailBeast said:
Make absolutely sure it full of fluid by checking in neutral.
Then I would pull the pan, check for debris.
Then pull the VB and air test it because it sounds like and internal seal or sealing ring leak if none of the above.
Also if 2nd has some sort of issue where it can't apply the band it can shift directly from 1st to 3rd, so be sure this isn't what it is doing by putting the trans in manual second.

An FYI, a plugged or incorrectly installed filter can cause a no 2-3 upshift also.
Click to expand...
Lefty71 said:
Well, we had a Frod that we threw an old trans that sat forever and never moved... The band popped loose off one end from rust in one spot on it's maiden voyage. Either way, it needs all new seals and rubbers after sitting that long, so it's gotta come apart. Also, there are micro line filters in two places on that unit., one at the gov. and the other in the valve body. I'd bet they plugged right up once you kicked up the rust inside.
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well, the trans has been out twice, and its been out for the second time since last nice, while I got it out, might as well replace the rear clutch seals, I replaced the entire front drum out of a bb 727 that I freshened up for my coronet, I thought that would've done it lol guess not oh well
 
Kody meile said:
well, the trans has been out twice, and its been out for the second time since last nice, while I got it out, might as well replace the rear clutch seals, I replaced the entire front drum out of a bb 727 that I freshened up for my coronet, I thought that would've done it lol guess not oh well
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theres a filter that's for the governor???
Lefty71 said:
Well, we had a Frod that we threw an old trans that sat forever and never moved... The band popped loose off one end from rust in one spot on it's maiden voyage. Either way, it needs all new seals and rubbers after sitting that long, so it's gotta come apart. Also, there are micro line filters in two places on that unit., one at the gov. and the other in the valve body. I'd bet they plugged right up once you kicked up the rust inside.
Click to expand...
theres a filter for the governor???
 
Well, it's probably the valve body, but I always like to check the drums on the pump with it mounted in my vise. That way I can see the piston move and the pack compress; so I can get an idea of how much clearance I have in real time. Is reverse delayed?
 
Engine Oil Pressure Test Kit I just picked up this oil pressure gauge kit (one actual gauge only) for cheap from Harbor Freight and used it yesterday on a 904 we rebuilt that had a big delay shift or no shift into 3rd . Decent quality, works great for testing the various ports for line, front and rear servos and governor. If no 3rd likely the kickdown band is not releasing, could be some sort of front servo issue, but like others have stated its likely the valve body. I'd meticulously inspect and clean.
 
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I did my first trans in 1980 and I've NEVER hooked up a pressure gauge to one. But I just wanted to interject with the possibility that the direct drum could be scored and the rings not seating good enough for third, but well enough to get reverse.
 
Upon reading the above post and seeing that someone has never used a pressure gauge on the trans I've come to the realization that I've been misled by the FSM and the Carl Monroe book among others...... gauges are for incompetents, a waste of time, are of no use and just for shade tree hacks who have no clue. What was I thinking. Much better ways to diagnose I now see. Good luck:thumbsup:. :rolleyes:
 
CudaFactHackJob said:
Well, it's probably the valve body, but I always like to check the drums on the pump with it mounted in my vise. That way I can see the piston move and the pack compress; so I can get an idea of how much clearance I have in real time. Is reverse delayed?
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Nope, reverse is strong and works perfect
 
CudaFactHackJob said:
Well, it's probably the valve body, but I always like to check the drums on the pump with it mounted in my vise. That way I can see the piston move and the pack compress; so I can get an idea of how much clearance I have in real time. Is reverse delayed?
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I did air check the front and rear clutches seated on the pump in a vise, I believe I ran 30 psi through it, everything seemed to be working like it should, the outer rubber piston seal for the rear clutch worked but I noticed when I was inspecting it, it was a bit "stiff" ish , its cold in my garage and I now the rubber would probably worm up and flare and seal when warmed fluid got in contact, I did otice too that when on the vise both clutch pack seemed to seal better then when in the transmission and pressure tested through the ports in the tranny. I did try and put some atf down the clutch ports and aircheck with I think 25-30psi. there was a light thud in the front clutch with air hissing. I know air can move a lot swifter than fluid can but wondering is that normal...
 
I don't care how a transmission works. I just want to fix it. If you can't figure it out by its behavior, a pressure gauge is only going to add to the confusion. Forty years and I've listened to all the "experts" talk about pressures to diagnose a problem; only to find out the real problem upon cracking it open. It's all BS for bench racers.
 
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I wouldn't say air moves faster than fluid. Air at 30 psi would be slower than fluid at 200 psi. Did you check the inside of the direct drum for ring scoring?
 
Aww ****, just use the manual, follow the process of elimination, use a pressure gauge as called for. Find the problem , done. Ive had enough with the hard-on slapping around here:eek: OP: good luck getting it solved. :)
 
12many said:
Aww ****, just use the manual, follow the process of elimination, use a pressure gauge as called for. Find the problem , done. Ive had enough with the hard-on slapping around here:eek: OP: good luck getting it solved. :)
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12many said:
Aww ****, just use the manual, follow the process of elimination, use a pressure gauge as called for. Find the problem , done. Ive had enough with the hard-on slapping around here:eek: OP: good luck getting it solved. :)
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lol ya I should, wanting to get it on the road before the weekend, well ill buy a gauge and a rebuild kit to git r dun
 
I don't see how a rebuild is going to change things; unless you're just frustrated and want to buy parts. I would stick a different valve body in it. Just make sure it matches up with the case casting configuration where there is differences in front of the rear servo. As a matter of fact, make sure the one you presently have matches up itself. Post pics.
 
CudaFactHackJob said:
I don't see how a rebuild is going to change things; unless you're just frustrated and want to buy parts. I would stick a different valve body in it. Just make sure it matches up with the case casting configuration where there is differences in front of the rear servo. As a matter of fact, make sure the one you presently have matches up itself. Post pics.[/Q
not frustrated, but I do want to put in new seals just to have them in, ill post pics probably when I get home, im on a computer at work
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I've never seen a pliable lip seal fail to do it's job unless it was cut or had begun to disintegrate. Even the ones that were rock hard would start to work after they warmed up. If the trans is still in the vehicle I wouldn't remove it. Did you check the governor valve on the tailshaft? Would the valve flop downward on both sides when you turned the shaft?
 
CudaFactHackJob said:
I've never seen a pliable lip seal fail to do it's job unless it was cut or had begun to disintegrate. Even the ones that were rock hard would start to work after they warmed up. If the trans is still in the vehicle I wouldn't remove it. Did you check the governor valve on the tailshaft? Would the valve flop downward on both sides when you turned the shaft?
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the seals are not torn or cracked, they look good to be honest, the transmission is out and apart on a work table in my garage, been out for a few days, the governor moves like it should when rotating the output shaft
 
CudaFactHackJob said:
I've never seen a pliable lip seal fail to do it's job unless it was cut or had begun to disintegrate. Even the ones that were rock hard would start to work after they warmed up. If the trans is still in the vehicle I wouldn't remove it. Did you check the governor valve on the tailshaft? Would the valve flop downward on both sides when you turned the shaft?
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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
 
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.
 
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