From this great web site...I've discovered the igear, and can't believe how it completely change the manners of my HHR. I use it in traffic and it behaves like a stick, and keeps the shifting to a minimum. I know that this has been discussed alot here, But I still have seen any definate info. Is it safe or bad to drive in igear alot? Any tranny guy's out there?

 

Doesn't the "I" gear just cut out the overdrive?

 

Nooo!

1) Shifts are crisper / harsher.
2) RPM are held much longer before shifts occur (>4500 RPM in 2nd; towing a trailer the other day the 3rd never kicked in below 80kph (50mph), whereas usually this happens around 45-50 kph)
3) You get definite engine compression when the throttle is released.

I don't use it very often, but it's good to have for towing, driving up/down mountains and winter driving.

Yves

 

I gear is best on hilly roads to eliminate hunting for gears. It won't hurt the transmission to use it but your fuel economy will be compromised. Here is GMs explanation:

I -- Intermediate position is also used for normal driving. However, it reduces vehicle speed without using your brakes for slight downgrades where the vehicle would otherwise accelerate due to steepness of grade. If constant upshifting or downshifting occurs while driving up steep hills, this position can be used to prevent repetitive types of shifts. You might choose Intermediate (I) instead of Drive (D) when driving on hilly, winding roads and when towing a trailer, so that there is less shifting between gears.

 

The only advantage that I can think of is that your GM brake rotors won't warp as quickly as they would when using D.

 

Brad you are truly a good kind of smart asss! So MPG is compromised? Now I wanna try it to see if I can get like 13 MPG! LMAO

 

Actually I have been using "I" a lot the last month or so since I read about it here, and my average fuel economy has gotten better. I think it depends on your driving style. In "I" you dont have to mush the pedal in order to downshift, which may use less gas when passing. If I notice that I am coasting for a while, I slip it into D.
I also enjoy the sweet engine tone up around the 4000rpm mark.

 

I slip in I gear every once in awhile for fun at lights to race myself I also use it during slick or wintery conditions to slow down before applying the brakes.

 

I f you experiment with I gear in around town traffic you will find you get better milage in most cases..this is because you wind up not lugging the engine at slower speeds.. though anything over 50 mph or around 2500 rpm will benefit D range...

 

I rented a Cobalt and drove up to Pike's Peak. I tried "I" gear on the way down to keep from heating up the brakes. Instead, the engine temp skyrocketed. When I put it in low, the problem went away.

You might want to check your engine temp next time you use it. See if that only occurs in very high altitudes.