This morning I hopped into my 84' 911 to go to work. It was about 31 degrees
Fahrenheit outside, so just a tad brisk to say the least. Anyway, my
faithful steed fire right up as always, and off I went. I came to the first
stop, and was pretty well slowed down (below 10kph) and started to slide it
into first. But as I did that, I cringed at the sound of gear grinding. It
just did it the one time (which was enough for me) on my way in. It seemed
once the car warmed up to operating temperature all was fine. I paid close
attention to the shifting, and it felt just fine as always. So then as I'm
leaving work (once again it was a bit brisk) I got a grinding of gears when
I tried to downshift to first at the stop. All this past summer no grinding.
So on my way home I stopped by the local Porsche mechanic and asked him
about it. Since the transmission was just rebuilt this past year I was
thinking that maybe it was low on transmission fluid, and needed more time
to build up fluid pressure. My mechanic explained to me just how the syncros
were set-up, and how the 917 transmission was using the same syncro design
that had been around a while up until the G50. He told me also that a common
mistake allot of folks make is to try and downshift to first gear above
10kph. I told him that I usually "coast" up to stops with the clutch
engaged, shifting at the last minute when the car is almost stopped anyway.
So I mentioned the cold weather aspect and asked if that could be a possible
cause? He agreed that it might be. I wanted to get the groups take on this
before I got to carried away with this.

Any ideas?

Thanks in advance,