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Fresh rebuilt 727 wont upshift

Posted: Fri Apr 07, 2017 7:37 pm
by Drewdayecono
Hey all, ive owned my swepty for a couple of months now and just got it registered and have started getting everything running as close to tip top as i can get it. When i bought the truck the 727 had been freshly rebuilt by a known transmission shop and was never put on the road after that. Ive been having issues with it not shifting from first to second or third in the drive position. Ive got park, neutral, reverse and 1 and 2. Ive loaded about 12 quarts of ATF in the transmission and already pulled the valve body and its 100%, the governor was free and undamaged when i removed and checked it. Ive set the kicknown valve to be as far to the rear of the transmission when at WOT. Ive gone in and set the bands for the front at 1.5 turns back from tight and 4 turns back from tight on the rear. Wondering if anyone has any idea what my issue could be, i always try to figure something out on my own before bothering others with my issues but im at a loss for what else the issue could be. Any help would be appreciated

Re: Fresh rebuilt 727 wont upshift

Posted: Sat Apr 08, 2017 5:18 am
by MadMC63
Trying to understand. You don't have upshift in drive but you do if you shift manually from 1 to 2 to d? Is this happening during driving conditions or are the rear wheels off the ground?

Re: Fresh rebuilt 727 wont upshift

Posted: Sat Apr 08, 2017 8:41 am
by Drewdayecono
Im not able to get anything in drive. Even when i shift from 2 to d i dont get an upshift. Absolutely nothing in drive

Re: Fresh rebuilt 727 wont upshift

Posted: Sat Apr 08, 2017 9:58 am
by PwrWgnDrvr
I'd be back to, or on the phone with, the "known transmission shop" that screwed it up!

Re: Fresh rebuilt 727 wont upshift

Posted: Sat Apr 08, 2017 10:49 am
by 712edf
I typed in your situation "google" & various people have had similar issues on cars. I would bet that if it sat for a long time something shrank or dried up inside.

If both Drive & Reverse go out then I have read its front clutch pack failure. If Reverse works then look into valve body.

I would contact the rebuilder. I wouldn't expect them to want to warranty it if its more than 3-6 mths. In their mind it has been put in use the minute it left their shop.

On one forum a guy said he would get the vehicle up to speed, shift into Neutral, then back into Drive & it would work. Worth a try I guess.

Bucky

Re: Fresh rebuilt 727 wont upshift

Posted: Sat Apr 08, 2017 4:26 pm
by pwadventurer
Drewdayecono wrote: Ive set the kicknown valve to be as far to the rear of the transmission when at WOT. Ive gone in and set the bands for the front at 1.5 turns back from tight and 4 turns back from tight on the rear.


I doubt its your problem but my service manual says after tightening to 72 inch lbs, back off 2 turns for front and rear bands.

For no drive, my manual says (a)low fluid,(b)hydraulic pressure to low,(C)oil filter clogged,(d)valve body malfunction or leakage,(e)faulty oil pump,(f) clutches or servos sticking or not operating,(g) torque converter failure.

Just sitting for a few months shouldn't cause any of these problems unless water got in there.
was the converter replaced when rebuilt?
Like pwrwgndrvr said, get a hold shop that rebuilt it and see if they will help.

Re: Fresh rebuilt 727 wont upshift

Posted: Sat Apr 08, 2017 8:00 pm
by MadMC63
I'm back to not understanding. Your truck never upshifts from or out of first gear? What does it do right?

Re: Fresh rebuilt 727 wont upshift

Posted: Sat Apr 08, 2017 8:04 pm
by 712edf
MadMC63 wrote:I'm back to not understanding. Your truck never upshifts from or out of first gear? What does it do right?
Sounds like he has everything BUT Drive.

Bucky

Re: Fresh rebuilt 727 wont upshift

Posted: Sat Apr 08, 2017 11:20 pm
by marklein
Put a gauge on the accumulator port on the passenger side of the trans, the port in the middle. You will only have pressure in forward gears. If it backs up, it is not the direct (front) clutch. If pressure looks ok, put the gauge on the governer port, near the mount, you should have approximately 1 psi per mph. Gauge should be capable of 250 psi, just in case you need to put it on the rear servo port to check reverse pressure. You either have a governer issue or valve body, the gauge will point you in the direction you need to go. Keep us posted, btw what year is the trans?

Re: Fresh rebuilt 727 wont upshift

Posted: Sun Apr 09, 2017 1:24 pm
by MadMC63
" Ive been having issues with it not shifting from first to second or third in the drive position." It stays in first gear all the time when shift lever is in the drive position?
" Ive got park, neutral, reverse and 1 and 2." It doesn't shift into third?

Re: Fresh rebuilt 727 wont upshift

Posted: Sun Apr 09, 2017 7:25 pm
by PwrWgnDrvr
MadMC63 wrote:" .........
" Ive got park, neutral, reverse and 1 and 2." .....
Those are the positions on the gear selector that work correctly.....P R N D 1 2....Apparently when the selector is in the D position it stays in first and does not shift to 2nd or 3rd. There is no shifting when in all other positions.

Re: Fresh rebuilt 727 wont upshift

Posted: Mon Apr 10, 2017 1:13 pm
by MadMC63
Disconnect the kick-down linkage at the trans so there is no external force on the lever and give it a try. Can't hurt.

Re: Fresh rebuilt 727 wont upshift

Posted: Tue Apr 11, 2017 11:29 pm
by marklein
Never run a torqueflite without the kickdown linkage, it is the lifeblood of that unit. Without it, line pressure does not get increased from minimum and slipping and burnt clutches and bands are the result. There are a number of possibilities, governer support bolts being loose, governer itself bolted on the support 180 degrees out, the governer itself being stuck, and a valve body problem. Best bet is to use a gauge and not guess where to look.

Re: Fresh rebuilt 727 wont upshift

Posted: Wed Apr 12, 2017 5:35 am
by MadMC63
Wasn't talking about forever. Diagnostics only. We know it wont shift for some reason. We also know that incorrect adjustment of the kick down linkage could result in the same drivability issue. Just trying to eliminate the most obvious external factor first.

Re: Fresh rebuilt 727 wont upshift

Posted: Wed Apr 12, 2017 7:24 am
by marklein
The OP states that the tv adjustment is all the way back on the trans at wot, so it is not likely an adjustment. The tv being out one way or the other usually only makes it late and firm or early and soft, it won't cause a no upshift condition. In my 30 years in the transmission industry, I have seen the term "fresh rebuilt" mean a lot of things. My bet in this case is a misassembly somewhere in the unit. Get a gauge on it, see if it has pressure rise by pushing the tv arm all the way back while idling in drive, then put a gauge on the governer port and drive it to see if it has governer pressure.

Re: Fresh rebuilt 727 wont upshift

Posted: Mon Apr 17, 2017 7:38 pm
by Drewdayecono
Thanks for all the input guys, ive had the valve body out and a transmission shop looked it over and gave me the ok on it. Same goes for the governor, which when removed wasnt stuck in any way. That being said i did get a pressure gauge and tested the line pressure which proved to be good although when checking the governor pressure i am getting nothing on my test drive of the truck. The transmission is a 1969 as is the truck in question, i had thought maybe the governor was mounted opposite to the way it was supposed to be but upon further investigation it can only mount the one way it should be. Upon opening the pan and everything else i have seen the bands all look good.

Re: Fresh rebuilt 727 wont upshift

Posted: Mon Apr 17, 2017 10:07 pm
by marklein
What were the pressures? Did u pull the tv and get pressure rise? If the valve body is deemed good, then all that is left is the governer. Could have a broken ring on the governer circuit, the governer support bolts may be loose. Here is how the system works, the valve body sends line pressure to the governer, that pressure closes the governer circuit off when not moving. Centrifugal force allows pressure to slowly rise as you go faster. It is a process of elimination to find your problem, you can pull the governer body off of the housing and air check the valve body through the governer housing. You should hear the shift valves move, will only take about 50 psi or so.