Be careful of dealer installed block heaters

[greg_g]

We use our tractor at those temps.

Note please, that I didn't say "use", I said "store". If you park your tractor out in the mud and the blood and the beer - and don't use a block heater - then of course go to a 60/40 mix. Remember also, John Deere says not to go stronger than 60/40, so you should check with MF to be sure.

But if you park you tractor in protected conditions, stick with the 50/50. Warm the engine up after starting so that the thermostat opens and you've got working temperature coolant circulating. At that point, an outdoor temp of -34F becomes academic. I'm also gonna wager that you've got some kind engine heater. When used correctly, they also make anything stronger than 50/50 just a waste of money.

//greg//