What are the benefits of using the D,1,and the 2 on the auto? I can feel it push harder when it's in the D position but what about the others? And at what speed is it not safe to shift? Hate to sound stupid but I am!

 

never race in OD,

use D
never manually downshift

use 1 and 2 when you want to stay in that gear.
id use 1 and 2 for autocross or burnouts a the staging lanes.

snow too i guess

 

When driving around town leave it in D. 1 means that the tranny will not shift out of 1st gear. 2 means that the tranny will only be in 2nd gear and will not shift out. D means all gears but your overdrive gear. (D) means all for gears, I only use this on the freeway, and use D for all of my city driving. Some will say to always leave it in (D) but I've always driven my cars like this, and have had zero transmission problems.

 

Benefits as opposed to what?

As far as I know, the only difference in using those different option is the number of gears it will use: D=3 gears, 2=2 gears, 1=1 gear).

I don't think there is be any real difference in performance.

The lower gears you use, the higher rpm's you are running and the more power/torque (to a certain extent, of course) you have available. Also, the tranny will downshift faster and therefore it feels/is a bit faster.

There is no difference in standing start, though.

If somebody with better info proves me wrong, then I'll stand corrected.

Later!

TS

 

I have no idea why you people drive like that..

In my 4L60e, i ALWAYS raced in OD.. I drove all day in OD and that is the way the manual suggests it be done.. Not only that, but anyone that I know that is a "Tranny guru" has said the same thing.

The tranny is electronically controlled.. it will choose the best gear for the job.

 

Depending on what gears you've got (2.73's or 3.23's) you may find that it's better leaving the car in Drive vs Over-Drive for a lot of your driving. Like you said, it "feels" like it's got a little more power, and that's because you're keeping the revs up and the engine is more in its power-band. Often times I won't put the car into OD until I've hit the highway.............with 2.73's it's just not necessary?! AND, keeping in D will prevent excessive up/down shifts. With lower gears though (even factory 3.23's) I'd say it's probably best just to leave the shifter in OD, but again, in town, or in heavy stop-and-go traffic, there's nothing wrong with holding the car back in a particular gear for a while.

 

2 things..... First Capn Pete, I couldnt agree with you more. And 2nd, 95GRNZ when the shifter is in 2, that is only 2nd gear not 1st AND 2nd. Try it sometime. Why GM did that I have no clue......

 

I'd say it's so that there's a little less torque to the back wheels in case you want to start in slippery conditions? But otherwise I'm at a loss too!

 

Why?

 

Really???

Learn new every day. Maybe I should try that one of these days...

 

that's their second gear start program, it's made for snow etc.

 

Now that you mentioned it... I think I might have heard about it at some point.

Tried this morning and sure enough: started from the second gear.

Somebody correct me if I'm wrong again, but I am pretty sure that wasn't the case in my LT1...

TS

 

Driving around in D/3rd in traffic doesn't do anything other than eat up gas ... yeah it feels faster because the TC is never locking up and you are stay high in your rpm band. OD/4th is your gas saver, it's where the TC locks up and driving in traffic is the worst on gas milage ... staying D/3rd will only exaceberate it.

If you are in traffic and you need to to down shift, all you have to do is double tap the accelerater and then floor it. The transmission will unlock and drop down to the appropiate gear.

D/3rd is good for your performance driving, when you don't want it to lock up ... ie road racing/whipping through the mountains ... personally I don't consider driving around in traffic performance driving.

To answer the original question ... OD - all routine driving, your gas saver ... D - performance driving, road racing, canyon carving drag racing ... 2 - when you need torque and autocrossing (depending on the course youll never get much over 60mph, no need to let the tranny shift into 3rd) ... 1 - ditto 2 on the torque.

Good Luck

 

I dont know about you, but i dont have a manual valve body pp


Are u sure? I'm almost 100% confident you are wrong unless there is some differance in Lt1/LS1 which i doubt.

At the track, the car in front of me broke down and i was still in 2nd frommy burn out. 10 min later i roll upto the line forgetting i'm in 2nd.

Launch and around the 1/8th i kicked this **** out of the rev limiter.

I KNOW i didn't start in 2nd because i was RIGHT next to a 12 second camaro till i hit the rev limiter. I also pulled a 1.9 or 2.0 60 60ft which isn't happening in 2nd gear start. My mph also looked ok




Why would they put an "2nd gear start" button in the firebirds if this was true?

 

first off-
are you SURE the TC doesn't lock till od ? some people verify this. put it in D, drive down the highway, keep foot on gas and tap brakes. do RPMs jump 100 -200rpms?


secondly, the whole point is to reduce wear and tear which comes from uneccisary shifting. I dont twant my tranny constantly coming in and out of OD to save 200 rpms. I just pop it into OD on the highway.