I have the stock 10 bolt 2.73 gears. Engine is an lt1 I plan to add a cam down the line but that's it.


So would this be all I need to go to 3.73 anything else??


http://www.ebay.com/itm/Motive-7-5-7-625-10-Bolt-Ring-Pinion-Set-3-73-Gear-/310633657822?pt=Motors_Car_Truck_Parts_Accessories&fits=Year%3A1988%7CModel%3ACamaro&hash=item48533575de&vxp=mtr

 

You need to know 2 series carrier versus 3 series.
You need to know 26 spline axles versus 28 spline.
You need to know Eaton versus Torsen versus the other "posi" carriers.
You need to know how to set up the ring and pinion pattern or you'll have a noisy rear.
You need to know how to correct your speedometer gears to some that will make the odometer / speedometer / ECM readings correct.

https://www.google.com/search?q=seri...r+thirdgen.org

should give you more reading. Each of those topics has been covered on here a good bit.

 

Yea I won't be installing them myself, my mechanic will

 

No, that is not what you need. That is the wrong gear for what you have. Read the FAQ about 10 bolt sticky first and then come back with any more questions that you have.

 

Will do.

And I keep seeing s 10 rear ends on craiglist. They won't work correct?

 

Correct. You can use the gears from a S10, but that's about it. If you use S10 gears you will need a 3 series differential, but not the S10 differential.

 

I can buy the used axles and use the parts but not the whole axle. So would that be a smarter option?

 

Just get a new thick gear for the rear end that you have. You can get a special thick 3.73 gear that will fit the 2 series differential that you have. These gears are after market only. Also get the best installatioin kit you can buy, and it won't be from Summit or Jeg's. Contact Tom's Differentials or Randy's Ring & Pinion.

 

Like this one?


http://www.ebay.com/itm/GM-7-5-CHEVY-10-BOLT-7-625-3-73-THICK-RING-AND-PINION-USA-STANDARD-GEAR-SET-/330841085427?_trksid=p2047675.m1850&_trkparms=aid%3D222001%26algo%3DSIC.CURRENT%26ao%3D1%26asc%3D11%26meid%3D6985607117220446729%26pid%3D100011%26prg%3D1005%26rk%3D3%26sd%3D260119775710%26

 

Yes, but don't expect that one to be quiet. Those cheap gears usually make noise. If you want it to be quiet then get a good name brand.

 

I never heard a noisy gear. So I have no clue what everyone is saying. To YouTube I go

 

Some make just a little whine and some sound like a fire truck is following you. Sometimes it's just in about a 5 MPH range, usually about 50 to 55 MPH and others make noise all the time.

 

My 3.73's started making noise and really scream at 60-70 mph depending on how much load is on the engine. Think it needs reset but i have the 3.73's for 2 series carrier in mine. Worked great. Best way to go if you have a good 2 series. Torsens are great and 2 series torsens are everywhere

 

I seen them on YouTube. Is there no way around the noisy gears? If they're cheap?

 

If you insulate the interior you may not hear it. I gutted my matting and its a banshee yelling

 

My car interior? Because I have 2 12s hard to hear anything but the music

 

-

 

If you set the gear pattern and back-lash correctly, you shouldn't have any gear noise. But if you are planning on taking the gears out, you should upgrade the carrier to a limited slip, or rebuild it if it already has one. Setting rear gears sucks, I would hate to do it twice.

 

I bought a 1986 trans am supposely with a 373 gear ratio in the back. My question is, how can i tell that its there. The only thing i noticed is that all my Gauges are screwed up, my Odometer says i go 10mph faster, and my RPM never goes higher then 3k, even i give it alot of gas :S

 

There are a few ways to tell your gear ratio. First is to take the cover off and count the teeth on the ring and on the pinion, divide the pinion tooth count by the ring pinion count. To avoid confusion, mark one tooth with a marker so that you know your start and finish point. Second is to put the rear end up on jack stands and put your transmission in neutral. Mark the tire and spin the driveshaft, counting the number of rotations of the driveshaft for one full rotation of the wheels. It won't be exact, but you should be able to figure it out to the closest gear ratio. Once you figure out your gear ratio, you can figure out the speedometer gears that you need for your transmission. There is a sticky thread about what speedometer gears you need for your gear ratio and size tire.

 

The gear ratio is stamped right on the ring gear. You just need to take off the cover and it should state 2:73 or whatever it is.

 

yes, it should be but is it the correct pinion for that ring gear to get that ratio? if you've already got the cover off to see the stamp on the ring gear, why not count the teeth?

 

You can not mix ring gears and pinion gears. If the ring gear says it's a 2.73 then it's a 2.73. You can't use a 2.73 ring gear with a 3.42 pinion gear. It just will not work. You can't even use a 2.73 ring gear with a 2.73 pinion gear from another set. Ring & pinion gears are mated at the factory and can not be mixed after they are lapped together.

 

I am aware of what is supposed to be, but you can't say that you've never taken anything apart and not said wtf did they do inside of here. My point is still valid, if you already have the cover off why not count the teeth.

 

I agree, counting the teeth is a good idea, but if someone had used a ring gear from one set and the pinion gear from another set he would have a VERY LOUD noise coming from the rear end. I don't think that is the case here.

 

A long time ago, I was taught not to rely only on what is stamped on a part, to verify everything. It doesn't take a genius to fake some casting numbers. CC cylinder heads, measure bore and stroke, etc. Same applies to rear ends, although it would be a little overkill to fake the gear ratio stamped on the ring when all you would have to do is change the tag by the cover. All I'm saying is I double check everything.

 

So would you recommend 3.73s and drum brakes or any 4th gen with disc brakes and wait for 3.73s?

 

I have some 3.73's from a 2 series carrier sitting around. They were professionally installed new and only had a few hundred miles before i broke the spider gears in the diff.

If you want them just PM me, you can have them for the price of shipping.


I don't think there was any damage to the gears but i'll look in the morning.