I dont want to go to HIDs or LEDs. Most knowledgeable people accept that the H7 uprades come at the expense of shortened life span. Has anyone identified the sweet spot where one is not changing bulbs every 4-6 months???
Depends on your electrical system, I find. Good earths and clean supply through a quality relay seems to help a lot. The sparkies reckoned inrush currents were killing them when too high.
If it's on trucks or other mobile equipment, vibrations don't help much either. We had a fleet of Volvos that ate lights every month or so (rubbish trucks, plenty of dust and rough roads). A heat-resistant foam rubber pad between the bulb and the reflector socket got us up to about 3-4 months, at least on the headlights. Similar vibration absorbers on the taillights helped with those globes too.
Obviously you want to be very careful about the heat resistance with headlight globes!
Hah, well, between the frequent electronics failures (due to vibrations, according to Volvo), the turbo failures, and those awful synchro 9-speed boxes...
Either would be appropriate!
In any case, we were glad to see the back of the fleet after the 5-year lease plan, and move back to International. At least their gear was reliable, if a bit agricultural...