Transmission not shifting properly?

Hi,

That is a hard question to answer. Before replacing or rebuilding, I suggest some simple checks.

First, is the transmission fluid clean and full? Also, have you scanned the can-bus for relevant diagnostic trouble codes? If not, that should be done as well.

Here is a link that shows how it's done:

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

Oftentimes, low or excessively dirty fluid will do what you described. As the transmission warms up, the fluid expands. That may be why you are getting the hard shift after it starts getting warm. It's a theory, but that is where I would start.

Here is a link that explains in general how to check transmission fluid:

https://www.2carpros.com/articles/how-to-check-and-add-transmission-fluid

I attached directions below specific to your vehicle.

Let me know what you find.

Take care,

Joe

I suppose I should have noted that I have done a fluid exchange and added BG transmission conditioner. There was a little change for the better, but not much. I scanned check engine codes, and nothing came up for transmission.

Hi,

How dirty was the fluid when you changed it? Was there a burnt smell to it or anything?

If not, the next thing I would suggest is to check the transmission line pressure. If it is within specification, then suspect it needs to be rebuilt. I am basing that on there being no codes.

I attached directions below for testing line pressure. Let me know if you are comfortable performing them.

Take care,

Joe

See pics below.