47Re in Worng Gear

M

motormayhem

New member
Joined
Aug 5, 2012
Messages
28
Hey guys, over last summer I noticed my transmission with 50,000miles would start out in 2nd sometimes after it had been driven for over 15 min or more. It would stay in 2nd at a light and when you hit the gas it would shift to first and run like a top through the gears. I had the bands adjusted and the gov pressure regulator/transducer replaced and it seemed to be gone as as it cooled down outside (below 90*) it was problem free.

Anyway today (about 6months later) I noticed it tried to start in 2nd maybe 3rd once today and downshifted to first when I hit the throttle. I also noticed when I floor the truck at WOT (not something I do normally) it revs to 3,000 before shifting out of first and will not shift past 2nd (holds around 3200) until I let off the throttle a little and then it will bang into 3rd and 4th. All shifts are very strong and it is not slipping. Anyone know what this could be? I really want to catch it early before it costs me a lot of money or leaves me stranded when I drive across the country in a month.
 
To fix the WOT no-shift condition, you need to loosen the TV cable adjustment a little where it connects to the throttle linkage under the hood.

To fix the no down-shift condition when rolling to a stop, you need to adjust the TV stop inside the pan to raise the minimum TV setting. I'd go (2) full 360* turns on the screw. If you raise the line pressure screw a bunch per the instructions below, go (2.5) full 360* turns clockwise from it's current setting.

Turn the large allen head screw in the middle of the picture clockwise to increase the minimum TV pressure which will cause earlier coasting non-throttle down shifts
ValvebodyPressure1.jpg




While you're working on it, before you drop the pan, you should hook up a pressure gauge to the middle port on the passenger side and see where the maximum line pressure is hovering when WOT on the highway. If you followed the transgo instructions and went with (4) turns on the pressure screw, it should be around 135 psi. If you add another (15) quarter turns or (4) full 360* turns to the pressure screw, this will get the line pressure up into the 150-185 psi range and give your tranny more holding capacity.

Turn the 3/16" allen head screw counter-clockwise for more pressure, it's the screw on the left in this picture with the orange spring
ValvebodyPressure2.jpg
 
Last edited:
Ok I will try and get some pressure readings in the next couple weeks. I didn't put the shift kit in so i'm not sure where it is at right now adjustment wise. Does the no-downshift condition happen by itself (needing to be readjusted) often or is this indicating a problem? It worked great the first 8 months I owned the truck and last summer when it was warm I noticed it would stay in 2nd at lights when it was hot out (90+*). I took it to the place that built it and they said it was the gov pressure unit and transducer and replaced that and did a band adjustment. It seemed to be better after (I also bumped the idle from 600-850 rpm which seemed to make it go away) that but did a couple times after that. I had to drive across the country about a week after the work was done so I wasn't ever able to get back over to talk to the shop that did the gov unit. The cooler temps in NY could also have contributed to the "fix" earlier this year. Its about 50* out now though and is doing what I described in my first post. I'm just a little concerned as I have to drive it to a new job in about a month and will be going from NY back to AZ and being in college really cuts into the transmission rebuild savings account/ its only got 60,000 miles and the motor isn't turned up that much and I mostly go really easy on it.
 
Up and downshifts are controlled by governor pressure. Even new electronics get tired after a while and I suspect your new governor solenoid is not fully closing when the fluid temp warms up and thins. If the solenoid doesn't fully close, it sends governor pressure to the shift valves and will cause it to hold gears or not downshift at all.

TV pressure counteracts governor pressure and allows for later full throttle upshifts. If you adjust the minimum TV pressure set screw, you can counteract the effects of your not 100% perfect solenoid (even though it's fairly new).
 
I have had that kit in my Trans for 3 or 4 years and haven't had 1 issue. I run higher line pressure that would kill stock solenoids in no time.

I have had decent luck with the upgraded borgwarner 50185 solenoid as well.
 
I may invest in one then as I'd like to run higher line pressure and keep those clutches nice.
 
You must log in or register to reply here.
Back
Top