[ChopTop]

Due to Kappa owner turnover & transmission issues I thought it would be helpful to give this answer a dedicated posting.

2009/WELCOME EDITION/Solstice/Pontiac Performance/Front cover: Rear view pic Mean GXP (matching yellow license plate TRC 432)
INSIDE:
KNOWLEDGE IS POWER -
LEARN ABOUT YOUR SOLSTICE

Pg 8
Q: My Solstice has a 5-speed automatic transmission with shift indicators of PRNDIL. When do I shift into 4, I or L?

A: The D position (overdrive gear) is used for most normal driving situations. It allows the transmission to shift into fifth gear, which provides the fuel-economy* advantage. The fourth postion (4) prevents the transmission from going into fifth gear. It's used for driving around town when you don't need overdrive.

The I position prevents the vehicle from shifting past third gear and should be used when driving on hilly or winding roads.

The L position prevents the transmission from shifting past second gear. It should be used only at extremely low speeds, such as in parking lots or when driving through mud or deep snow.

*EPA estimated mpg 19 city/27 hwy (Solstice GXP with auto); 19 city/24 hwy (Solstice with auto.).

 

[yosemitemike]

I like shifting it down into the I position while driving through a tunnel with the top down.

 

[KappaKadet]

This, for those who don't wanna read the owner's manual?

 

[thende]

Weird on m 07 Gxp. Low will give me 1-3.....

 

[ChopTop]

Posted this mainly for folks who make the mistake of doing what I did, and thinking D was for any reason like from days of old. However, since our auto’s are computer controlled 5 speeds the only reasons auto users should engage D is when highway speeds are being planned. For around town driving then it's 4, and for spirited driving on hilly or winding roads, than L.

Placing the auto in the correct position for the type of driving you want to engage in helps the transmission and computer from overworking and getting confused since it constantly monitors the transmission to choose the correct algorithm for the type of driving it's expecting.

Auto users have complained about shifting issues during high spirited driving events (clunking, hard downshifting, etc.) I believe it because the computer is getting confused about which gear the transmission should be in vs what gear it’s manual placed in.

 

[Preacher]

Thanks ChopTop; Good read!

 

[ToniCipriani]

"The fourth postion (4) prevents the transmission from going into fifth gear. It's used for driving around town when you don't need overdrive."

I wonder if that means I've been doing it wrong all along to skip shift from 3 to 5 all the time when I'm doing 60km/h...

 

[RedOne07]

I like shifting it down into the I position while driving through a tunnel with the top down.

Why ? because it shifts down ?

I do that by stepping on the gas.

 

[phil1734]

I always thought it a little odd that the auto in these cars had 4 options for forward propulsion, only one less then the manual...

...if you have to think about it that much...