Gearing differences - '04 vs '06

[andyschneider]

So, I've been in a quandry as to why my wife's '04 Pilot 4WD gets better gas mileage than my '06 Pilot AWD, even when we switch vehicles for a couple of days (so the driver and road differences are taken out of the equation). Mine is now up to 6500 miles, so I figure the motor is getting close to being broken in....

As I've discussed earlier, the 1-2 shift point happens at a much higher rpm in the '06 than in the '04, so that contributes a bit. But I wondered about gearing and whether there's a difference. What I noticed over the past few days may be the root of the mileage difference. At 70mph on the same road, same wind, same temps, the tach on the '04 reads 1850 (appx) while the tach on the '06 reads 2200 (appx). I verified that both vehicles are in their top gear and the torque converter had engaged. So, this tells me that the '06 will do worse on highway drives than the '04, and the 2mpg difference between the two vehicles supports this.

Anyone have any data supporting this gearing change between the model years? What have folks with '06 AWD's been getting for mixed driving mileage?

thx - andy

[deparson]

Originally posted by andyschneider

I verified that both vehicles are in their top gear and the torque converter had engaged.

I am interested to know how you determined this? Was it by 'feel' or did you plug something into the OBD port?

-D

[andyschneider]

Originally posted by deparson


I am interested to know how you determined this? Was it by 'feel' or did you plug something into the OBD port?

-D

Once I got to the cruise speed, I slightly kicked the throttle a bit and then felt/saw 2 RPM reductions after settling back down - 1 for 5th gear, and 1 for the converter. I had thought the converter in the '06 wasn't working, but I can see it kick down as I watch the shifts....

andy

[jcantanixon]

IIRC they made the gearing change for 5th gear for 2005. There's been a couple of discussions about it.

[GreenMachine]

Originally posted by jcantanixon
IIRC they made the gearing change for 5th gear for 2005. There's been a couple of discussions about it.

Ditto. It had to do with the transmission frequently downshifting or unlocking the torque converter for mind increases in speed. So the revised gear ratios gave you a higher rpm at highways speeds, and the result is the transmission doesn't have to gear hunt as much.

[andyschneider]

Originally posted by GreenMachine


Ditto. It had to do with the transmission frequently downshifting or unlocking the torque converter for mind increases in speed. So the revised gear ratios gave you a higher rpm at highways speeds, and the result is the transmission doesn't have to gear hunt as much.

Well, as far as "seat of the pants" driving, it's definitely made it better. The '04 has to hunt for gears more often, especially on long inclines, and the '06 has more "spirit" when driving. But I think I'm paying the price with highway MPG. But the window sticker is the same for the '04 and '06, and that's sort of what I'm trying to understand.... Higher 1-2 shifts and higher rpm's while on the highway doesn't seem to lend itself to similar MPG's....

andy

[jay]

Originally posted by andyschneider


Well, as far as "seat of the pants" driving, it's definitely made it better. The '04 has to hunt for gears more often, especially on long inclines, and the '06 has more "spirit" when driving. But I think I'm paying the price with highway MPG. But the window sticker is the same for the '04 and '06, and that's sort of what I'm trying to understand.... Higher 1-2 shifts and higher rpm's while on the highway doesn't seem to lend itself to similar MPG's....

andy

I'd bet the gearing change for the transmission and tuning change for the engine didn't require re-doing the EPA estimate.

[a2Pilot]

Originally posted by andyschneider


Well, as far as "seat of the pants" driving, it's definitely made it better. The '04 has to hunt for gears more often, especially on long inclines, and the '06 has more "spirit" when driving. But I think I'm paying the price with highway MPG. But the window sticker is the same for the '04 and '06, and that's sort of what I'm trying to understand.... Higher 1-2 shifts and higher rpm's while on the highway doesn't seem to lend itself to similar MPG's....

andy

I agree. My wife and I also notice a big difference in "seat of the pants" driving feel between our old 2003 and our new 2006 Pilot. BIG improvement! We've not really tracked our gas mileage though.

[jcantanixon]

Originally posted by andyschneider


But the window sticker is the same for the '04 and '06, and that's sort of what I'm trying to understand.... Higher 1-2 shifts and higher rpm's while on the highway doesn't seem to lend itself to similar MPG's....

andy

Doesn't the EPA use some lame speed for "Freeway" testing? Like 50mph steady for 20 minutes or something? I think that the rpm difference at that speed probably doesn't change the mpg much.