Not shifting into 5th

[neoryan7]

I started to notice this a few months ago but wasn't too sure what it was.

I noticed that my rpms while cruising were not the same as a few months prior. I have a 4cyl auto with 90k miles. Before this happened at 60mph I would have been at 2krpm and at 75mph I would be at 2500rpm.

Now at 60mph im at 2200ish and when im at 75mph Im at 2800rpm.

I tried counting how many times the car shift but I couldn't come with a concise number.

I did notice after a 30min drive and after checking the fluid it is 1/4inch overfilled. Can this be the problem? The D light is not blinking and I can't tell if my CEL is on because I have kpro.

[timot_one]

You should still be able to read a code on your ECU.  Just ignore all the codes about sensors malfunctioning and what not since they are connected to KPro.  The fact that your tranny fluid is overfilled might be part of it too.  Have you drained the excess fluid yet?

[CrackerTeg]

I've heard of auto trannies not shifting properly because of over filling. I'm not sure if it causes loss of pressure because of high volume or the reverse effect. Then again, the auto trannies these days shift so smooth you'll hardly notice the 1-2 shift and think you missed a gear. Maybe someone else with better experience on Honda auto trannies can chime in. I've only had MT Hondas.

[CYANiDE]

I've heard of auto trannies not shifting properly because of over filling. I'm not sure if it causes loss of pressure because of high volume or the reverse effect. Then again, the auto trannies these days shift so smooth you'll hardly notice the 1-2 shift and think you missed a gear. Maybe someone else with better experience on Honda auto trannies can chime in. I've only had MT Hondas.

My 1st to 2nd and 2nd to 3rd make my head rock back and forth. Nowhere near smooth lol. I have to do a drain and refill 3x after the winter is over.

[CrackerTeg]

My 1st to 2nd and 2nd to 3rd make my head rock back and forth. Nowhere near smooth lol. I have to do a drain and refill 3x after the winter is over.

Like I said:

Maybe someone else with better experience on Honda auto trannies can chime in. I've only had MT Hondas.

[CYANiDE]

My 1st to 2nd and 2nd to 3rd make my head rock back and forth. Nowhere near smooth lol. I have to do a drain and refill 3x after the winter is over.

Like I said:

Maybe someone else with better experience on Honda auto trannies can chime in. I've only had MT Hondas.

Yea, I wish I had a MT. I'd say take out excess fluid (remember car should be warmed up when you check). Then take it for another spin.

[Mike]

I've read that over filling the transmission can cause the fluid to foam up, and cause problems. It's possible that if the fluid is over full the it's causing your issue take out the excess, and hope you don't have a tranny issue!

[timot_one]

The K24 AT's haven't been known to have problems like the V6, have they?  I'm not really up on the AT's.

[neoryan7]

I hope thats the problem imma try to take out the excess tomorrow. For the time being anyone have any other ideas?

[timot_one]

I'd say removing the extra would be a pretty good first step.  You may end up racking your brain about the other "what ifs" when it could be as simple as too much fluid.  When was the last time you changed your transmission fluid?

[CrackerTeg]

I'd say removing the extra would be a pretty good first step.  You may end up racking your brain about the other "what ifs" when it could be as simple as too much fluid.

I'm with Tim on this. Definitely the most logical first step.

[neoryan7]

I did the change about 2 months or so ago. I took off the drain bolt and let it all run out. Waited about 30min then poured 3 bottles of honda atf-z1.

[Mike]

Your transmission could very well be over full, Just simply pulling the plug out of the transmission isn't likly to drain all of the fluid. There are alot of places inside the valve body that would still hold fluid even with the plug out.  That is why the suggested procedure is to drian, fill, drive and then repeat a couple of times to get as much of the old fluid out as possiable.

[NVA-AV6]

A little overfull (as you described) would not cause a problem, now with the stock ECU throwing codes and not getting all data because of KPro, now that can cause a issue, tranny shifting in these cars is very dependant on feedback from the TPS and MAP sensors, it sets up the "grade logic" that honda has in there for shifting, if the TPS is disconnected your stock ECU could be reading as you are always at or near WOT and therefor does not shift into 5th and thinks you are climbing a steep hill or trying to accelerate to pass and keeps it in 4th. How are you other gears shifting? At what RPMs?

[NVA-AV6]

Also if the fluid was foaming due to being sloshed around by spiining tranny componets it would be easily seen by pulling out the dipstick while the car was ideling, the stick would have foamy (lots of air bubles) fluid on it.