What causes difficult cold shifting in manual transmissions?

[demarpaint]

Originally Posted by khittner
Originally Posted by MountainBloke
Can difficult cold shifting have any other sources other than viscosity?
Why would I suddenly develop it out of the blue with fresh Honda MTF that's only run on 3000 miles?


Failing clutch hydraulics can cause only partial disengagement, which would increase shifting difficulty, particularly when the gear lube is also not up to operating temp.

True, combine that with cold fluid being "thicker" and that would compound the issue until things warm up a bit. I'd try a clutch slave cylinder bleed if possible. I had a similar problem and bleeding the clutch solved it for me.

 

[wagsrk08]

My 2012 Tacoma has mainly shifted smoothly even in below freezing to sub zero temperatures. Never a dragging feeling, but sometimes from 1st to 2nd a little stiff when below freezing. I didn't change out my original transmission fluid until truck had 80,000 miles earlier this spring 2019. Added Redline MT-90 75W-90 GL4 at that time. Really can't feel big difference in shifting but a solid piece of mind knowing it's changed. Have only had a few below 32 degrees this year and it's shifted fine.