Not at all, as far as Iâ€™m concerned â€“ a diesel is â€˜warmed upâ€™ when it ignites the fuel with compression. Thatâ€™s why itâ€™s important to use the correct oil and keep the engine well maintained. Only under load will a diesel warm to operating temp; it will take forever to warm just idling.
JDC is right. One of the efficiencies of diesels is that there is little waste heat generated at idle. They need to be under load to really warm up. As soon as it will run smoothly, put it in gear and drive gently until up to normal operating temps.
You must forget your old ( gas) ways.
I would recomend at the very least 5 minutes, but 10 is better. After about 10 minutes the oil has warmed a little, and has begun to thin, thus allowing for better circulation when you bring the RPM up, instead of immediatly putting it in gear and driving with cold thick oil that doesn't flow or circulate as well as warm or hot oil. You may have full oil preasure at idle when the oil is cold (because it is thick), but it doesn't circulate as well. However, after about 10 minutes you should drive away to heat the rest of the oil up more quickly, but you have "prepared" the engine, oil, and car for the stresses and pressures of operation by allowing for sufficient engine warm up. I would recomend you run Valvoline 15W-40 All Fleet Plus in the Diesel. Enjoy.
Both the diesels get between 5 and 10 mins warmup ( depending on how late we are ) , mostly to get the oil and trans a little warm . We live on a 100kmh road so have to boot it straight from the gate , I think that is too hard on a cold engine.
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