woodrep

Help! I think my transmission is messed up. When slowing down to stop at a stoplight or stopsign the truck seems to stay locked in gear and doesn't release to idle. Don't know if I can explain this one well enough. It is not slipping or shifting erraticly during normal driving, just when youre almost at a complete stop. Has anyone had something like this happen? What could it be? I pulled the trans dipstick and the fluid doesn't smell burt nor is low, the only thing that I have done lately is had to speed up in traffic to avoid a lady fixing to sideswipe me and when i hit the skinny pedal the truck downshifted and couldnt seem to decide what gear to lock into. I immediately got off of it so that it could equalize itself and hit a solid gear. Help me out guys and let me know if I could explain this situation any better or provide more info.

05 4x4 QC, Xzillaraider on 60HP, 75,000 miles
Thanks
Scott

05CTDN8

Sounds to me like the Torque Converter is messed up.

vzdude

Governor pressure transducer and solenoid. Very common problem. Do a search to find out how to fix it. I posted the info a little while back.

woodrep

Thanks VZ,Shakin, I would believe the transducer and solenoid issue, but the torque converter not so sure that I would think it has issues since it drives, shifts and everything normally while driving. Like I said earlier, the only thing that it does do is act like the transmission can't decide to disengage or release itself right at the point of a complete stop. Almost like if it was a standard and you let out on the clutch a little then stepped back down on it. Know what I mean? Has anybody else had this same or similar situation happen with their 3rd gen Automatic?
Feedback please>
Thanks
Scott

woodrep

By the way, what is safe for the trans temp? Mine got up to 179 today.

vzdude

Yup! ^ It's real common even on the 2nd gens too! I've actually done two already this week! One set on a truck and one set on a 3/4 ton van!

woodrep

VZ does my 05 have the 48re like yours? I am good with doing my own maintenance and repairs, but I've never gone into a transmission, so I'm kinda nervous about this one. I was hoping to eventually put in a Goerends VB and TC on my truck, because I don't really like the way that this trans shifts and such anyway. Not that it's not getting the job done in daily driving, but it doesn't seem to shift firm or "make up its mind" what gear to lock into in certain acceleration instances. Are you a mechanic or do automotive performance?

vzdude

Yes, and Yes!

There is really nothing to it. Drop the pan, take the filter off, 3 -torx screws, 4 -7/16 bolts and replace the solenoid and transducer. Very simple. If you can change your trans fluid, you can do this.

woodrep

You da man! What does the transducer and solenoid exactly do? Also, do you recommend a flush or drop and refill.

woodrep

Forgot to ask, are these dealership only parts or do you get them at the local Napa or Parts store?

vzdude

Dealer parts.
I don't get to concerned about tranny flushes. I change it enough that it doesn't get that bad.
The transducer tells the ECM what pressure the governor is putting out vs. what the ECM is calling for. Thats why I change both. The solenoid could be sticking giving the wrong pressure, or the transducer could be reading the wrong pressure! I hate to do anything twice, especially dropping the tranny pan!
The pressure solenoid is a duty cycle solenoid that cycles to control governor pressure inside the trans. The more it is open the lower the pressure. The more it stays closed the higher the pressure. It just continually opens and closes and the computer determines the duty cycle. Kind of like an injector pulse width. Just with tranny fluid.

J BODY

Never seen the gov psi transducer or solenoid cause the issue described above...but first time for everything. There was an issue similar to this back in 01 on the V10 47re trucks and a software upgrade took care of it....of course that was back in the dark ages and not applicable to what you have, but still shows it "could" be of an electrical nature.

woodrep

Thanks VZ I will call a dealer tomorrow and ask for pricing.
Thanks for your wisdom.

vzdude

I was assuming when he said disengaging, that it was staying in second gear, and he had to accelerate to get it back into first. I may have made some assumptions, but I think he's on the right track. I have about 80 of these trans ( 47 and 48's) in the fleet I work on, and replace a bunch of these sensors for they "won't go into low gear" problems.

Woodrep - are we talking about the same thing, just to make sure?

J BODY

I think you're on the correct track......for some reason I was on the thought trail that the lock up was staying engaged on coast down.....must have been too late for me to be reading. I agree that the sensor/solenoid throw would be the route to take.