my 2005 5.9 48 re wont go into drive, changed tcc pressure sensor shift solenoid

 

Any codes? How many miles on it?

 

203000 no codes had it tested and pressures were good . could it be TPS ??

 

Assuming this is a diesel??

Don't think TPS would cause it. Usually, at around 45 mph, it should drop into O/D. Is it shifting normally otherwise? TCC engaging?

 

yes diesel ,yes shifting normally otherwise (for a dodge) lol

 

Its just a solenoid.... if it wasn't working, I would think the computer would complain about it. Is the trans temp, or O/D off lite on?

 

no trans temp light, o/d -tow haul light will turn off and on as I command , (so it works ) the total story is when pulling trailer on hiway it started to tach up about 200 rpm s when going up overpass in o/d then slipped momentarily then drove home 200 miles still slight 200 rpms in o/d . I changed pressure sensor and shift solenoid ans tranny felt good but no longer goes into o/d . took to some on that hooked up to computer while driving it and said pressures were good at times commanding 4th but not going in to 4th (sometimes) changed tcc and overdrive solenoid. so do you think maybe one of the ones I changed was bad also (even if pressures were good) or a different solenoid. BTW thanks for your time and thoughts

 

Shouldn't tow in O/D..... the clutches simply can't hold on tight enough, and they slip, and burn.

The 200 RPM change is TCC engaging/disengaging. If it's 'bouncy', likely TPS is bad, or just flaky.

RPM should drop pretty good on 1-2 shift, and again on 2-3 shift, then slight drop when TCC engages, then a significant drop when it goes into O/D. Which one isn't happening?

 

all shifts normal just no o/d

 

Is the PCM actually requesting overdrive??