1996 Impala SS Gear Change
John Koegler
Hello All,
Finally, I was able to take my toy down to the local drag strip. I had
modified the intake and replaced the stack exhaust and wanted to see how this
improved the time. My best run of the day was 15.076, almost .5 better than
its all stock form. But because its great barge weight, 4200, and its
driver, 230, the stock 3.08 gear are, what I believe, too tall. I want to
change to 3.73, but when I called the local Chevy dealer, They gave my all
kinds of hell.
Basically, they said it would mess us the ABS system, take 5 hours,
void all warranties (which does not concern me much), and basically, they
would not take the risk of changing the gears. My question, is this true?
How would this affect the ABS system? Obviously, the speedometer is
affected. I read all the time in my magazines, guys changing the gears on
their Firebirds and Camaros. Personally, I think these guys are not too
intelligent.
If you have done this swap in your car (1993 or newer with ABS) could
you please tell me the cost and the parts needed, if you can. Thanks for the
help.
John Koegler
Tin Injun
> How would this affect the ABS system? Obviously, the speedometer is
> affected. I read all the time in my magazines, guys changing the gears on
> their Firebirds and Camaros. Personally, I think these guys are not too
> intelligent.
buy a LT1 nestled in a 3600lb car rather than a "4200lb barge".
I bet 3.73s would help an SS though. Good luck.
As for ABS, some sensors are at the wheels and some are in the
differential, depending on car/manufacturer. The ECM will get roayally
confused, though the Hypertech Power Programmer may fix this. I dunno
for sure, ask those "not too intelligent" F-bod owners, they'll know . . . .
BV
Ed Runnion
Tin Injun <bvau...@odin.cbu.edu> writes:
>> How would this affect the ABS system? Obviously, the speedometer is
>> affected. I read all the time in my magazines, guys changing the gears on
>> their Firebirds and Camaros. Personally, I think these guys are not too
>> intelligent.
>
> So, what makes you any different? At least they had enough sense to
>buy a LT1 nestled in a 3600lb car rather than a "4200lb barge".
He meant the Dumbass Chevy Dealer, not the Camarabird owners!
Maybe he wanted to be able to take along two other "full-size"
people when he drove the car?
I LOVE my Impala, and yes I have driven several 93+ Camarabirds
before. The Impala is not as fast (true) but as an everyday
vehicle for me (I am 6'4" and well over 200 lb) it was
the better choice for me.
> I bet 3.73s would help an SS though. Good luck.
> As for ABS, some sensors are at the wheels and some are in the
>differential, depending on car/manufacturer. The ECM will get roayally
>confused, though the Hypertech Power Programmer may fix this. I dunno
>for sure, ask those "not too intelligent" F-bod owners, they'll know . . . .
>BV
More Impala owners are going for 3.42's, since you can use the
F-body 3.23 ECM and it works perfectly (Speedo is off something
like 0.1%).
The Impala ABS reluctor is in the differential BTW. The
Hypertech can compensate for aany Gear ratio change you want :
if you wanna put 4.11's in your Impala, it will deal with it!
For more info, check out the Impala SS homepage at:
--
Ed Runnion, Flash Memory Reliability Engineer
Texas Instruments, Houston TX USA
Email : eru...@hubcap.clemson.edu
Web Homepage : http://www.clemson.edu/~erunnio/ed.html
Douglas Braeckel
Tin Injun <bvau...@odin.cbu.edu> writes:
>> How would this affect the ABS system? Obviously, the speedometer is
>> affected. I read all the time in my magazines, guys changing the gears on
>> their Firebirds and Camaros. Personally, I think these guys are not too
>> intelligent.
>
> So, what makes you any different? At least they had enough sense to
>buy a LT1 nestled in a 3600lb car rather than a "4200lb barge".
> I bet 3.73s would help an SS though. Good luck.
> As for ABS, some sensors are at the wheels and some are in the
>differential, depending on car/manufacturer. The ECM will get roayally
>confused, though the Hypertech Power Programmer may fix this. I dunno
>for sure, ask those "not too intelligent" F-bod owners, they'll know . . . .
>BV
Tin,
I think you are a little confused here, you need to re-read the
original post and calm down a little. He wasn't saying that the F-body
owners are unintelligent, he was saying that the "mechanics" at the GM
dealership were not too intelligent. I think we have all witnessed the
fact that most of the people behind the counter at GM don't have a clue
what is going on.
Later......
--
------------------------------------------------------------------------------
"What a waste it is to lose one's mind. Or not to | Doug Braeckel
have a mind is being very wasteful. How true that | dbra...@comp.uark.edu
is." -- Vice President Dan Quayle | www.uark.edu/~dbraecke
P. J. Remner
In a previous article, bvau...@odin.cbu.edu (Tin Injun) says:
>> How would this affect the ABS system? Obviously, the speedometer is
>> affected. I read all the time in my magazines, guys changing the gears on
>> their Firebirds and Camaros. Personally, I think these guys are not too
>> intelligent.
>
> So, what makes you any different? At least they had enough sense to
>buy a LT1 nestled in a 3600lb car rather than a "4200lb barge".
Hmm? I believe he was referring to the dealer's mechs when he said that.
'Sides, 4200 pounds is about right for an intermediate car.
> As for ABS, some sensors are at the wheels and some are in the
>differential, depending on car/manufacturer. The ECM will get roayally
>confused, though the Hypertech Power Programmer may fix this. I dunno
>for sure, ask those "not too intelligent" F-bod owners, they'll know . . . .
Is the Impala SS's ABS system four-wheel *independent* antilock or is it
two channel front/one channel rear? If it's the latter, there is probably
some sort of triggering device (magnetized insert) in the ring gear.
Without it, the computer would see that the rear axle (and wheels) are
not moving, so it figures that the brakes are locked, and there you are
with effectively no rear brakes every time you try to stop.
That's the way it was done for the early Ford rear-wheel antilock brakes,
and that's where the sensor is for the illegal hidden Winston Cup
traction control devices. It's a hunch. Maybe you could scrounge up
a 3.73 r&p from behind certain Winston Cup garages... <g>
--
'72 429 Thunderbird: Because size *does* matter.
Chewy coffee is good coffee.
This post was not sent by P. J. Remner.
It was the result of sunspots, and is completely random.
Doug Braeckel
On Tue, 14 May 1996, Tin Injun wrote:
> > >> How would this affect the ABS system? Obviously, the speedometer is
> > >> affected. I read all the time in my magazines, guys changing the gears on
> > >> their Firebirds and Camaros. Personally, I think these guys are not too
> > >> intelligent.
Taken out of context! See the original post included below! This is how
flame sessions start.
> > I think you are a little confused here, you need to re-read the
> > original post and calm down a little. He wasn't saying that the F-body
>
> Well, the above would back me up. I wish I had the sentence or
> two ahead of that. Who cares. And I wasn't getting uptight. I rarely
> flame, but when I do, everything gets roasted :)
>
> > fact that most of the people behind the counter at GM don't have a clue
> > what is going on.
>
> Go to ANY dealer. Dang, they are all morons. I know several
> folks that work in dealer service departments. What dumbasses. . . .
That's the key word, ANY dealer. Arkansas, Tennesse, Florida, you name
it. Although the Pontiac dealer in West Palm Beach has a friendly staff.
> BrentVaughan
>
Brent,
I am not trying to cause trouble here, I just get tired of seeing people
arguing with eachother because one took something out of context. I
have included the original post, and I think you will agree that John
wasn't mouthing off about F-Body owners but about the uptight, indifferent
GM counter help. I hope that this post will put this to misunderstanding
to rest with no hard feelings.
John better not be talking about F-body owners since I own a 1979 10th
Anniversary Trans Am. :-)
No hard feelings.
Doug.
From: John_K...@om1.cv.hp.com (John Koegler)
Newsgroups: rec.autos.rod-n-custom
Subject: 1996 Impala SS Gear Change
Date: 13 May 1996 16:01:42 GMT
Organization: Hewlett Packard
Hello All,
Finally, I was able to take my toy down to the local drag strip. I had
modified the intake and replaced the stack exhaust and wanted to see how this
improved the time. My best run of the day was 15.076, almost .5 better than
its all stock form. But because its great barge weight, 4200, and its
driver, 230, the stock 3.08 gear are, what I believe, too tall. I want to
change to 3.73, but when I called the local Chevy dealer, They gave my all
kinds of hell.
Basically, they said it would mess us the ABS system, take 5 hours,
void all warranties (which does not concern me much), and basically, they
would not take the risk of changing the gears. My question, is this true?
How would this affect the ABS system? Obviously, the speedometer is
affected. I read all the time in my magazines, guys changing the gears on
their Firebirds and Camaros. Personally, I think these guys are not too
intelligent.
If you have done this swap in your car (1993 or newer with ABS) could
you please tell me the cost and the parts needed, if you can. Thanks for the
help.
John Koegler
Tin Injun
> >> How would this affect the ABS system? Obviously, the speedometer is
> >> affected. I read all the time in my magazines, guys changing the gears on
> >> their Firebirds and Camaros. Personally, I think these guys are not too
> >> intelligent.
> Hmm? I believe he was referring to the dealer's mechs when he said that.
> 'Sides, 4200 pounds is about right for an intermediate car.
Okay folks. Sorry. I "cut" the original message in the wrong
place. I shoulda known it was the dufus certified "techs." Sorry.
I don't "go around lookin' fer flames" no matter how bad this
looks :)
Yeah, 4200 lbs is a nice size.
This will teach a Pontiac lover to read about Chevy posts!
BV
Scott Widmer
John Koegler wrote:
> Finally, I was able to take my toy down to the local drag strip. I had
> modified the intake and replaced the stack exhaust and wanted to see how this
> improved the time. My best run of the day was 15.076, almost .5 better than
> its all stock form. But because its great barge weight, 4200, and its
> driver, 230, the stock 3.08 gear are, what I believe, too tall. I want to
> change to 3.73, but when I called the local Chevy dealer, They gave my all
> kinds of hell.
> Basically, they said it would mess us the ABS system, take 5 hours,
> void all warranties (which does not concern me much), and basically, they
> would not take the risk of changing the gears. My question, is this true?
> How would this affect the ABS system? Obviously, the speedometer is
> affected. I read all the time in my magazines, guys changing the gears on
> their Firebirds and Camaros. Personally, I think these guys are not too
> intelligent.
> If you have done this swap in your car (1993 or newer with ABS) could
> you please tell me the cost and the parts needed, if you can. Thanks for the
> help.
John,
I agree that the stock 3.08s are a bit tall for the SS, given it's
sporty nature. Many Impala owners have made successful ring & pinion
swaps and have nothing but praise for this particular modification.
Most of the members of our group (The National Organization of 94-96
Impala SS Owners) have installed 3.42 gears, which is an optional ratio
(GU6) in the Cadillac Fleetwood (cousin of the Impala). Only a few have
reported doing the 3.73 swap.
Which ever ratio you choose, you'll need to replace the ABS reluctor
with one for the appropriate gear set. It's this little ring which
allows the PCM to monitor the motion of the rear wheels relative to the
vehicle's speed. Without the correct reluctor, the ABS will not
function. The part costs under $10 and is available through the GM
parts department. BTW, the Caprice/Impala uses a 3 channel ABS system.
The two front wheels are independent (on separate channels) while the
rear wheels are combined into the third channel.
The next issue you'll need to address is recalibrating the speedometer.
This is done via reprogramming the PCM. Many aftermarket programmers
(Hypertech, Z-Industries, etc.) have custom PCM programs available for
the Impala and can incorporate a gear change modification. Figure on
spending about $300 for a PCM upgrade.
Lastly, if you're not doing the swap yourself, find a reputable and
qualified place to do the work for you. Most GM service departments
will probably shun the idea of doing this kind of work, but all of them
_should_ be capable. Personally, unless I had connections, I would
avoid a GM service center all together! Figure on paying for about 4-5
hours of labor plus miscellaneous shop costs (gasket, fluids, etc.).
Here is a list of GM parts required to complete the 3.42 gear swap.
Note that the only difference in parts between the 3.42s and 3.73s are
the actual gear set and the reluctor.
Part Description GM P/N
3.42 Gear Set 26041514
20 tooth reluctor 26018945
Axle seals (2 req'd) 554631
Pinion spacer (crush collar) 1234726
Pinion Nut 1260823
GM Limited Slip Additive 1052358
Good Luck!
-Scott Widmer
srwi...@cle.ab.com
'96 Impala SS, Black
Eugene Slater
Douglas Braeckel wrote:
>
> Tin Injun <bvau...@odin.cbu.edu> writes:
>
> >> How would this affect the ABS system? Obviously, the speedometer is
> >> affected. I read all the time in my magazines, guys changing the gears on
> >> their Firebirds and Camaros. Personally, I think these guys are not too
> >> intelligent.
> >
> >buy a LT1 nestled in a 3600lb car rather than a "4200lb barge".
> >differential, depending on car/manufacturer. The ECM will get roayally
> >confused, though the Hypertech Power Programmer may fix this. I dunno
> >for sure, ask those "not too intelligent" F-bod owners, they'll know . . . .
>
>
> Tin,
>
> I think you are a little confused here, you need to re-read the
> original post and calm down a little. He wasn't saying that the F-body
> dealership were not too intelligent. I think we have all witnessed the
> what is going on.
>
> --
> ------------------------------------------------------------------------------
> "What a waste it is to lose one's mind. Or not to | Doug Braeckel
> have a mind is being very wasteful. How true that | dbra...@comp.uark.edu
> is." -- Vice President Dan Quayle | www.uark.edu/~dbraecke
know a hell of alot... very helpful too, gone extra miles, enough for
bonus miles (free tickets)....