94 wagon rear end ratio?

[rodcain]

I just bought a 94 wagon with 104,000 mi.
I'm disappointed with the power on take-off.
It's alot slower than my 91 sedan with a
305 and 200,000 mi. I'm confident the 91
would win a 1/4 mi. race against the 94.
This has to be due to ring and pinion ratios,
doesn't it?

[96capricemgr]

Dual electric fans on it?? If so probably has 2.56 gears where I think the TBI cars were often 3.23 or sometimes even 3.42.

Look at the SPID list and give us the codes that start with "G" and we can look up what ratio the car came with.

I have a wagon with 2.56 and it sucks. I haven't done anything about it though because I have my sedan for speed. Took it out yesterday, felt GOOD. Wagon will occasionally squawk one tire, the sedan in cold weather like this will break both tires free at 50+mph on dry pavement. So for me tweaking the wagon would be pointless, it would never compare.

[j cAT]

Originally Posted by rodcain

I just bought a 94 wagon with 104,000 mi.
I'm disappointed with the power on take-off.
It's alot slower than my 91 sedan with a
305 and 200,000 mi. I'm confident the 91
would win a 1/4 mi. race against the 94.
This has to be due to ring and pinion ratios,
doesn't it?

these 94 caprice wagons came with the LT1 engines ..also the trailering pkg would change the rear differential ratio..check the glove box door for the coding on what the vehicle came with ..

the wagon has more weight than the sedan , the wagon has more power than the 305 however ..I would make sure you have good fuel pressures , replace fuel filter , use some techron injector cleaner ..

there are other componets that would effect power like the cat converter restricted/or muffler..the distributor/ignition plugs , could be in need of replacement ...if the vehicle has low power and poor MPG these items need attention/testing...

cleaning the throttle body with throttle body cleaner and cleaning the MAF sensing wires with CRC MAF cleaner is good routine maintenance ..to keep the throttle response working correctly.

[rodcain]

Do the codes your referring to have several groups of four?
It is visible with the tailgate down/open. I'll write them down
when it's daylight and not so cold.

[96capricemgr]

The codes are on a sticker visible with the tailgate open. bunch of three digit codes.

The ones starting with a "G" are axle related, that is what we need here. LT1 is the engine option code so you will see that too.

[j cAT]

Originally Posted by rodcain

Do the codes your referring to have several groups of four?
It is visible with the tailgate down/open. I'll write them down
when it's daylight and not so cold.

This should have the info required...if not an internet search should provide you will all the info your looking for..


G75 : AXLE REAR, 3.62 RATIO
G76 : POSITRACTION REAR
G80 : AXLE POSITRACTION, LIMITED SLIP
G81 : POSITRACTION REAR AXLE
G82 : AXLE REAR, 4.56 RATIO
G84 : AXLE REAR, 4.10 RATIO
G86 : AXLE, REAR, LIMITED-SLIP
G87 : RING GEAR, 8.50 INCH
G89 : RING GEAR, 7.50 INCH
G91 : SPECIAL HIGHWAY REAR AXLE RATIO 3.08
G92 : AXLE REAR RATIO, PERFORMANCE
G94 : AXLE REAR, 3.31 RATIO
G95 : AXLE REAR RATIO, ECONOMY
G96 : AXLE REAR, 3.55 RATIO
G97 : AXLE REAR, 2.73 RATIO
GH0 : AXLE REAR, 3.54 RATIO
GH2 : AXLE REAR, 2.29 RATIO
GH3 : AXLE REAR, 2.77 RATIO
GH4 : AXLE REAR, 2.92 RATIO
GK9 : AXLE REAR, 4.63 RATIO
GL3 : AXLE REAR, 6.17 RATIO
GM1 : AXLE REAR, 2.59 RATIO
GM3 : AXLE REAR, 3.45 RATIO
GM8 : AXLE REAR, 2.56 RATIO
GMC : PLANT CODE PONTIAC, MI, USA
GN9 : AXLE REAR, 4.11 RATIO
GQ1 : AXLE, STD RATIO
GS1 : AXLE REAR, 2.73 RATIO
GS3 : AXLE REAR, 3.73 RATIO
GS4 : AXLE REAR, 3.70 RATIO
GS5 : AXLE REAR, 4.11 RATIO
GS6 : AXLE REAR, 4.56 RATIO
GT1 : AXLE REAR, 2.56 RATIO
GT2 : AXLE REAR, 2.29 RATIO
GT4 : AXLE REAR, 3.73 RATIO (DUP WITH 5 X 1)
GT5 : AXLE REAR, 4.10 RATIO (DUP WITH GT8)
GT7 : AXLE REAR, 3.33 RATIO
GT8 : AXLE REAR, 4.10 RATIO (DUP WITH GT5)
GTY : AXLE, WIDE TRACK
GU1 : AXLE REAR, 2.41 RATIO
GU2 : AXLE REAR, 2.73 RATIO
GU4 : AXLE REAR, 3.08 RATIO
GU5 : AXLE REAR, 3.23 RATIO
GU6 : AXLE REAR, 3.42 RATIO
GV1 : AXLE REAR, 2.73 RATIO
GV2 : AXLE REAR, 5.83 RATIO
GV3 : AXLE REAR, 3.08 RATIO
GV4 : AXLE REAR, 3.36 RATIO
GV5 : AXLE REAR, 3.55 RATIO
GV7 : AXLE REAR, 4.11 RATIO
GV8 : AXLE REAR, 2.72 RATIO
GW2 : AXLE REAR, 2.56 RATIO
GW3 : AXLE REAR, 2.56 RATIO
GW4 : AXLE REAR, 3.31 RATIO
GW5 : AXLE REAR, 2.73 RATIO
GW6 : AXLE REAR, 3.27 RATIO
GW8 : AXLE REAR, 4.10 RATIO
GW9 : AXLE REAR, 2.93 RATIO (DUP WITH GU3)
GWL : SPRING, RR, 9000 LBS CAPACITY
GX1 : AXLE REAR, 3.70 RATIO
GX2 : AXLE REAR, 3.07 RATIO
GX3 : RATIO,TRANSAXLE FINAL DRIVE 3.33
GY2 : AXLE REAR, 3.31 RATIO
GYS : RATIO TRANSAXLE FINAL DRIVE 3.65

[rodcain]

Thanks for the codes. It's just what I thought.
I have the 2.56 rear end. I wish it was the 3.77
or even the 4.11. I wonder if these ring and
pinions are available for this rear end?
I would like to pull a 14 foot atv trailer with 2
atv's. About 1,800 pounds.

[Blt2Lst]

Originally Posted by rodcain

Thanks for the codes. It's just what I thought.
I have the 2.56 rear end. I wish it was the 3.77
or even the 4.11. I wonder if these ring and
pinions are available for this rear end?
I would like to pull a 14 foot atv trailer with 2
atv's. About 1,800 pounds.

Gears should be available for your application.
Some 3.73's should get you rolling pretty good.
You will also have to recalibrate the speedometer gears to get an accurate speedometer reading.

[j cAT]

Originally Posted by rodcain

Thanks for the codes. It's just what I thought.
I have the 2.56 rear end. I wish it was the 3.77
or even the 4.11. I wonder if these ring and
pinions are available for this rear end?
I would like to pull a 14 foot atv trailer with 2
atv's. About 1,800 pounds.

I had the 3.08 ratio towed a 4,ooolb boat with the 350 tranny ..got good power ...3.23 would have been better..

you don't need 4.11 gears ...

[96capricemgr]

2.93 was the best ever factory installed in an LT1 wagon.

3.42s are NICE, just be sure to get the ABS reluctor http://www.focuztech.com/product/abs...impala-ss.html

Actually you will need to replace the differential too because the ring gear flange for the 2.56 is way to the right to make room for the big pinion gear. The above linked guy can get you the posi bearings gears and reluctor. You would still need someone to install them though because this is a fairly involved project. Most guys that build engines themselves wont tackle the gears.

Then you will need reprogramming from someone like www.pcmperformance.com

These are both companies I have done business with and while they are not the most popular they are actually GOOD which can NOT be said for the most popular vendors in most cases.

Just a warning, this project is going to come in up around $1000+, figure $200 for gears and reluctor, $500 posi, $100 bearings and fluids, $150 tuning, installation labor can vary greatly, say $175-250 on average.

It would feel like a whole new car and probably increase non-highway fuel economy and not hurt on the highway.

The 2.56 thing was just a BAD BAD idea, the only way those would have been the right choice is if the car never had to accelerate and cruised at 80mph. I use Drive instead of overdrive in mine a LOT and it does not hurt economy because under 60-65mph OD just lugs the engine.

[rodcain]

It sounds like shopping for an entire rear end with
the ring and pinion that I want would be the easiest
solution. What years and models of Olds,Chevy's,
and Buicks should I look for the higher ratio rear ends.
I'm capable of doing the mechanical part of the swap.
I would possibly need some reprogramming afterwards?

[96capricemgr]

I believe the 91-93 wagon(Raody, Caprice, Custom Cruiser rears would fit just fine and were available 3.23 for sure and I think even 3.42. Worst part about that swap will be cracking the brake lines free from the center junction on top of the axle.

You will need reprogramming to correct the speedo, car will drive fine but the speedo will be off.