Upgrading 4d Maglite - expected battery life?

[BigStu]

Hey guys,

New user here but I've been lurking for a few weeks.

My sis just bought me a 4D Maglite as one of my bday presents and I've ordered a 3w 360 lumen bulb for it. Was wondering what kind of battery life I can expect from it - I understand LED is more efficient but we're also talking around 3.5x the brightness of the stock incandescent bulb in this case. I did have a quick Google but couldn't find much.

[xxo]

I have a 350 lumen LED drop-in in my old 4D Mag and got over 3 hrs. running on AA Eneloops. I would guess alkaline D's would last around 15 hrs, but I don't know - I don't use alkalines because they are not rechargeable and they leak.

[Lynx_Arc]

Likely the 360 lumen LED bulb is about 3.6 watts so it is drawing perhaps 3/4 of an amp or so at 6V if you add a little loss in conversion via a buck circuit. I"m guessing probably 6=7 hours of near full brightness dropping off over another 6-10 hours to 10% brightness perhaps.