It's possible. It would have helped if he were to have taken a closer listen as it was passing by and pulling away, that would have been a great aid in determining if it was a diesel as they sound very distinct.
I spotted this prototype Jeep Wrangler. He noticed I was taking pictures and started to drive away very quickly. As he started to pull ahead of me I noticed a bit of “dark” smoke come out of the exhaust. Could this be the 3.0 Ecodiesel Wrangler? They are using LED headlights on this model.
My guess is 1/2 of that for the average off-roader here when in a lower gear. It's the hardcore guys that hammer it through steep inclines. No average off-roader will stress their brand new Wrangler that much.In a scenario where you need to actually crawl or get over a rock of some sort, you're definitely not hitting 4600rpm at all. Way too high and I can imagine by that time it may induce spin