Proof of auto trans / temp problems

[Chaz]

Big thanks to Nordic and Chaz . This post has been very helpful . Although I dont have trans temp issues , the 3rd / 4th overdrive in my auto is
one issue that I would like to address in the future. As I get the auto seviced annually , this was a question I asked about and the auto mechanic
said sorry nothing they could do, and I live and work close to major freeways and travel 20 minutes each way , sometimes wont slot into 4th
until the last five minutes of the journey . - frustrating . .and costing me in fuel ...

Hi Boots,
The first thing that comes to mind is the temperature switch inside the transmission. If it doesn't come up to temperature, it won't go into 4th gear. This would most likely be a faulty temp switch unless for some strange reason your transmission isn't getting warm - unlikely. You could have the switch replaced or just bypass it and see if it goes straight into 4th when the engine is cold.