O.K., first winter with a diesel here in NJ and I have a few questions. Thanks in advance for any answers.
1. When do I need to install anti-gel, temperature-wise, and are there any good brands or is generic O.K.?
2. I am currently using Amsoil 15W40 full synthetic. Am I correct in thinking that this is a proper weight oil for NJ winters where 10-15 degrees F nights are common?

Lastly, is changing the thermostat in an '85 300D as easy as it looks? I am getting tired of cool drives, and the cardboard in the grill is not cutting it.

Thanks, and I pray you all have a Merry Christmas, and grand holiday season, and the best New Year of your lives.

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'85 300DT--215,000 miles
'82 300DT--255,000 miles