I've only had my 2000 4WD sportage a few months and now that it is cold in the mornings the manual transmission is hard to shift. Is this normal or is the oil in the trans. to thick to let it shift easily like when it is warm? After it has run a while it is back to normal shifting. I thought maybe the leverage on the gear shift was such that a little stiff oil would cause a big difference the way it shifted on all sportages.