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Old 08-13-2012, 01:00 PM
Carnivora Carnivora is offline
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Location: Ocean Springs MS
Join Date: Apr 2011
Posts: 61
Mein Auto: 2011 335i 2008 X5
Tips for maximising gas milage in hybrid.

Ok, so I was wondering if any of you Active Hybrid owners have any tips or knowledge about maximizing your milage. I thought I would put my observations down as well.

I have the 10 X6 active hybrid. My old vehicle was a 4.8 X5 08. I was averaging 15 in my X5 based on my driving. With the X6 I'm averaging 19.5. Not bad considering I went up two turbos, 130 hp, and 175 ft. lbs.

So, the first thing I noticed is that it does not benefit, at all, to drive electrically. You don't use any gas, but as soon as the battery is depleted, the engine kicks on and the engine starts charging the batteries, and the mpg goes . The only thing that maximises mpg is maximizing what goes into the batteries while braking.

So up until about a month ago, I was driving a completely different style. I was trying to maximize my milage by driving like a grandma at starts and coasting as far as possible in neutral whenever possible. So I was using the electric motor quite a bit, the engine didn't kick in until around 20 mph. This put quite a drain on the battery, and I noticed that sometimes when I stop the battery would hardly charge at all. I would coast in neutral when possible but put it back in gear before slowing down (doesn't charge in neutral). But sometimes when I would stop, the battery would charge quite a bit. I've also seen that the gas milage seems to be the best around 38-39 miles per hour. The problem is that the engine want's to switch off at that speed and you charge and discharge the batteries. It seems as though it causes the batteries to get hot and then when you have to stop, very little energy goes back into the batteries.

So now I'm driving quite different. Off the line, I try to get on the gas and use "electric only" as little as possible. It still uses the electric motors to bump the acceleration but because the engine is doing most the work, less drain on the batteries, which means less "engine charging" the batteries. (I get about 13-14 mpg while "engine charging" at 42mph)

I still coast as much as possible in neutral. In gear, it has quite a bit of engine braking and sometimes I can coast for 5 times as far if I time the lights just right.

I try to drive at least 42 mph to keep the engine from switching off. Really the only charging I want is from braking. Also, at 42, it runs in 7th gear. The faster I get to 7th gear the better. Sometimes if I have to drive less than 42, I put it in sport mode and manually gear it to 6th or 7th depending on the speed.

Got to pick my kid up from school. More later.
I wish.
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