Is my Tranny normal?

I have a 86 300zx, with 140,000 on it. I have had it for awhile, and it runs very well. It shifts really nice too. My question is, when it is a cold day, is it normal for the transmission to warm up before it shifts in to overdrive. I live right off a highway, and cold mornings it take about 2-3 miles, before it shifts into overdrive. Is this normal, or something I need to fix? Thanks for the help.


One more question, the servos, for the a/c, are they really a nightmare like i have read they are?

When it's cold it can take a while for the fluid to warm up and start circulating properly. Automatics are a maze of passages and check valves, thick cold fluid doesn't get moving through everything right away. You can check to make sure you have enough fluid and if it's dirty or just been a while since it's last fluid change you could try that. However if it's only on cold days and there is no unusual sounds, vibrations, or rpm wavering that go with the delay there shouldn't be a problem.

z31 auto's (fail-o-matics) will not shift into overdrive before the car warms up. this is normal.