Opinion on Gears package?

[Craig 2000 TA]

Hi guys... My rear pinion seal is leaking and needs to be replaced so I was thinking about putting the TA rear end girdle on while its done... then I got to thinking about the gears and how lots of folks have had real good improvements with a gear upgrade. Now my first question would be what is my stock Gear ratio? I have a 2000 Trans Am (Non WS6) with a 6 speed. My second question is how high, or low I always get confused with that, should I go? My car is MOSTLY street cruised... I take it to a track rental once in awhile but I drive it to the track and home. No trailer queen here. My ultimate plan I guess would be to gather all the parts and bring them all in a box to a local shop and pick up the car with the old parts in the box and the new ones in the car The best pricing I have found so far is from Thunder Racing...

MOTIVE Gears, in your choice of ratio...3.42, 3.73 or 4.10
Or, STRANGE Gears (2 or 3 series carrier) for $25 additional
RATECH Complete Gear Installation Kit
2 Quarts RED LINE Synthetic Gear Oil
1 Bottle GM Limited Slip Differential Additive
TA Performance Rear End Cover Girdle
TA Performance Stud Kit

All that for 459.00 plus 25 bucks if I want Strange Gears. Anyone have good or bad experience with either of these companies gears? The evil side of me want to go for the 4.10s while the good side of me suggests that 3.73 might be better. I'm assuming since its not offerred that 3.23 is my stock gears? Any idea what kind of improvement in the 60' and 1/4 mile I could expect from a 3.73 or a 4.10? Sorry for the long post but I know diddly squat about rears. Thanks.

[Joe K. 99 Zeee!!]

Look on the inside of your glovebox lid for option codes.

GU5=3.23
GU6=3.42

Info from this site... http://www.f-body.org/tech/

3.23 or greater means you have a 3 series carrier. ThunderRacing is a great dealer. They also had the best package for my needs. I ordered Strange gears for 2 series carrier (mine had 2.73 stock) along with the high end install package and basically had my rear differential rebuilt using it.

What you have down should be good for your needs though. GM Motive gears have been described as the quietest running gears. As far as what ratio to use....I can't really suggest one since all my reasearch was done with an Auto trans in mind.

From what I've seen there's not much difference between 3.42 and 3.73. People who run at the track with M6's get the best times with 4.10's....but this might not be best for you since you keep it on the street a lot.

[Joe 1320]

Stick cars all came with 3.42s

The best gear for a stick car seems to be 4:10s due to the double overdrive of the 6 speed. Still great cruising rpms, yet a great acceleration gear. Go with GM motive gears, they are the quietest for our 7.5 inch rear.

[Craig 2000 TA]

Thanks for the info guys. I did talk to a guy who had 4.10s in his SS and he said in sixth he can cruise about 200- 2500 RPM which seems reasonable to me...I can do 1500 RPM now.

Somone mentioned something about a Solid Pinion Spacer and that I should use one if I go through with this... any thoughts on that? I suppose I would have to have someone with LS1 edit change the computers mindset on what gears I was running? The install shop should do that though.

[Injuneer]

The "crush sleeve eliminator" solid pinion spacer is made by Ratech, and may be included in the Ratech install package. Or an option with it. Check it out.

You aren't likely to find a shop that can alter your PCM for the new gear ratio. You need to buy either a copy of LS1_Edit and a cable, or a Hypertech Power Programmer.

4.10's are about 20% steeper than the 3.42's that come with all M6's. You should be turning 1,600rpm at 70mph with the 3.42's. That will increase to 1920rpm with the 4.10's.... not a serious increase. Might make 6th gear a little more usable. I ran 3.73's when my car was an M6, and I liked them. They give you a 9% boost in rear wheel torque, and would make the 70mph cruise at 1,750rpm. A much more subtle change than the 4.10's.

[Craig 2000 TA]

Thanks for the input Fred. I do have to say it surprises me that most shops wouldn't be able to set the gears to something different in the computer. Wouldn't most shops need to be able to get into the computer to do a tune like after a heads and cam package? I assumed most shops that specialized in this would have a multi liscense for LS1 Edit or some such. Either way my shop of choice says they can do it. I just found it surprising.

[Joe 1320]

It is amazing to me that most shops won't touch the computer on a gear change. I suppose they are less computer oriniented and stick with the basic mechanical stuff. There is a "piggyback" module that SLP sells that corrects the speedo without doing a re-program. Part # 63007 for LT-1 cars, # 63008 for LS1 cars. Available seperately, or part of a performance gear package.

[Injuneer]

The only way for a "non-performance" shop (one not limited to late model F-Bodys/Corvettes) to change the PCM settings for gear ratio would be with the GM/OTC Tech-2 tool. That's a $3,000+ investment, and most (non-GM Dealer) shops don't have them. Or if they do have them, they only know how to read the PCM, not change the programming. Then, on top of that there may be the legal issues of emissions of monkeying around with the computer. Federal law sets substantial fines for things like that.

[Craig 2000 TA]

Damn Fred... once again you prove to be a bastion of knowledge! The Shop I am looking at having it done in says that if they do the install they can change the puter for 100 bucks. They also have a dyno and have a policy that says if you have some work like cams or heads done there they will read, report and delete any codes set for free. They do specialize and from what I understand they only work on LS1s so maybe they can do it because they run LS1 edit. I have never seen LS1 edit so I am not sure what its capable of.

As for the extra Module... Thanks for the info Joe. I will mention it to my mechanic and see what he says... maybe its cheaper then a reprogram.