B4000 weird symptom. reverse doenst engage when cold.

[ryan2022]

Hi guys,

My Auto trans 2001 B4000 doesn't engage reverse when its cold the odd time in the morning. Once its run for a few seconds, or I put it in drive then back to reverse its fine, and shifts perfectly after that.

Its really smooth and solid on the highway, its the only issue.

Is reverse slowly going? When its warm it doesn't do it. The fluid is fresh and at the correct level. Weird.

 

[mazdab40004x4]

I know this is about a month old. I had a similar issue on my 94, but I don't know if the 2001 is the same. Reverse was OK on mine, but shift into drive and it wouldn't get out of first gear until it warmed up a bit. Then would shift fine. I was about ready to throw in the towel on the tranny, but it turned out to be a simple loose vacuum hose. It was attached but wasn't fully seated. Seated it properly and it started shifting fine (well, as fine as a ranger/bseries will ever shift), even in ultra cold weather.