All diesel fuel will lose cetane over time just like gasoline will lose octane and go bad over time.
I don't see how biodiesel should be any different.

On the brighter side. I was told by my diesel fuel supplier (I use it for commercial emergency generators) just this morning that diesel additives for algea/mildew will help keep the cetane up.

If your going to store fuel for long periods of time you may want to use an additive.
There's a company near me that makes a product called diesall. It goes for $20 a quart.
Check commercial diesel suppliers in your area you should be able to find something to use.

Danny

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1984 300SD Turbo Diesel 150,000 miles

OBK member #23

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