Two Letters Re: The Big Chill Causes Diesel Gelling Problems in the Lower 48

The blog post regarding diesel gelling is correct for the most part. However there are solutions that are easy and inexpensive. There are many aftermarket additives that will keep your fuel oil from gelling and also raise the cetane level of the fuel. The cetane level is similar to the octane level of gasoline, the higher the better it burns. DieselKleen, Stanadyne and others are good choices. My 6.0L Ford F350 gets a full mile per gallon better mileage with the addition of DieselKleen and I have not had a single engine problem in over two years of operation. One gallon of DieselKleen is about $17 dollars at Wal-Mart and treats 300 gallons of diesel fuel. For climates where freezing temperatures are a concern, make sure to purchase an additive that has anti-gelling properties. DieselKleen in the silver container is the anti-gelling formula. Hope this helps. – Jim T.


Those of us who live in Canada (in my case 60 miles northeast of Toronto) and drive diesel vehicles (1990 diesel Land Cruiser, HDJ81) know the problem of diesel gelling all too well.
However there are measures you can take to lessen the problem, e.g. add an anti-gelling diesel additive with every fill up, the amount varies with brand). In addition install a heater on your oil pan, a block heater to warm the coolant, and lastly and by no means least, wrap your battery (two batteries, in my case) with an electrically heated battery blanket. Also, use a lighter weight oil in the winter, such as 5W40. Regards, – Mark N.

JWR Replies: As this article (cited in Eric’s letter) describes, unfortunately the currently available selection of additives do not work in preventing wax dropout in the new USLD formulations.