I live in northern MN and just put a Cloud Rider winter front on my truck. It helps it warm up a little quicker and it finally gets hot and stays hot. My question is about the tranny temp, without the winter front it would never get off the 100 peg, now it gets about 140 or so with the outside temp between 0 and 20F. My question is what is the optimum temp for the Allison and at what point should I start to let some cold air in the front to cool it down. Not towing or hauling anything at this point.

That's actually cool for the Ally they'll run about 200 in the summer, but it's way better than the 100 degrees I may occasionally see without the front installed on mine. Getting a warmer trans is one of the better reasons for having the cold front installed, too cold isn't good for the engine or trans.

Don't worry about it unless you start working it on an unusally warm day and see it get hot, but that's not too likely.

I run around 160 in the summer and 140 with the winter front(factory vinyl since i'm still waiting for my cloud rider to show up).

So it seems normal to me for this time of the year.

JB,

I get about the same temps as you do down here in the Cities. I added a tranny heater so when it get's really cold my fluid is warm when I start out.

Ditto on mine with the stock winter cover.