Tallguy67

Gents,
I asked a question about this the other day but it was buried in another guy's thread so not surprised I didn't hear much. Hijacking threads is a bad etiquette anyway. Here is the deal. In this part of Alberta it often gets to -30 for days on end with the occasional dips to -40. At those temps a perfectly good battery is only putting out 10% of its rated output. That concerns me since these diesels take a fair bit of power to heat the intake grid and then crank over the bejeesly big high compression engine. For all of my other vehicles I have always used battery blankets/heaters in conjunction with the block heater. I could have sworn that I read a while ago that there was some sensor under one of the batteries that would not appreciate a battery blanket. For the life of me I can't find any posts to confirm or deny my memory. So, here is the question. Is there any reason I shouldn't put a battery blanket on each of my batteries to help the poor guys out?

2500Ram

You are correct on the sensor under the battery, my memory is as vague as yours but believe it was a temp sensor to adjust the alternator power output to not overcharge a frozen battery. Since your battery will be up to temp I can't see a reason not to use a battery blanket but again my memory isn't as good as it used to be.