Just installed my 3.73's about 200 miles ago. I'm getting a whine when I am giving it a little bit of gas, other than that it's pretty quiet. When they were installed, they marking compound looked almost dead on and the backlash was at 0.09. I also had the preload of the pinion nut at 15 in lbs. Any ideas on how to correct the whine? It seems to be getting worse.

 

What brand of gears do you have? I have Richmond's and they whine, especially when I am decelerating. I wonder if this is a problem or just the way they are.

 

I don't know anything about gears, if someone could help me out?

I'm getting LT Headers, Y pipe with cats, I have a cat back system, I have my PCM tuned, TB bypass, LPE CAI, and a 160* thermostat. With these mods, what rear end should I get, it's an a4 97 Formula. I was looking at 3.73. I don't understand these type 2 and type 3 carrier stuff? If someone could help me out that would be great. I plan on getting the LT Headers, Y-pipe and the gears at the same time and having them all installed at the same time. I also am eventually going to get a torque converter. If someone could explain these carrier's, that would be awesome, and if they could provide links to the gears I would need. Thanks!

edit: Also, where can I get them installed? What kind of shop? Can I get them installed with the LT Headers, and the Y?

 

Strange 3.73 (For 2 Series Carrier)

The Gears for either a 2 or 3 series carrier depend on what type of carrier you currently have. For instance if you have 2.73's and want to upgrade to 3.73's you would have to buy either 3.73's for a 2 series carrier or upgrade your carrier to fit a 3 series gear.

 

Which one would I have to use with my stock 2.73? I have a 97 Formula. What carrier would I use with the 3.73 then? Thanks for your help I take it I have a 2 series carrier.

 

You will need to buy gears designed for your 2-series carrier. That is what I did. I also had the 2.73 gears. I will say that my car does not even feel the same anymore! It pulls hard without me having to force the trans into first gear. The gears are noisy and I run 800+ more RPMs at highway speed, but it is well worth it. IMO...

 

So I will need 3.73 gears for a 2 carrier awesome. What brands are good? Motive, Richmond..?

is this what i'll need?

 

Those gears in the link are for a 3 series carrier. If you have 2.73's, you will need gears for a 2 series carrier.

http://thunderracing.com/catalog/?ac...&vid=4&pcid=67

 

Yeah, I saw that, but those are like 400 bucks. I thought gears were only like 190?

edit: Ah nvm, I was looking at the whole packages Will there be anything else I'll need to replace when I do this? I will need to get my PCM retuned after the Headers and Y-pipe along with the gears. I also wanna throw a cam in there.

***I am lookiing at my sticker price from when the car was bought in 1997. It says "Rear Perfomance axle, 3.23 ratio" Does this mean I have a 3 series carrier?

 

yes, you have the 3-series carrier. 3.08 and below is 2-series and above 3.08 is 3-series.

 

About the gear whine, both sets of Richmond 3.73s I've had made more noise than stock. The 1st set were very loud on decel and moderately loud on accel and cruise. They broke after less than a year. The 2nd set are much quieter but have some whine on accel. The 2nd set installed by a driveline shop and the 1st under warranty by the dealer I bought car from.

 

Did you ever find out why your Richmond's broke? I thought they were supposed to be real strong. I hope I made the right choice buying the Richmond's.

 

The set that broke were installed and set up by the dealer I bought the car from under warranty. I bought the Eaton and gears and they covered labor. They were very loud, especially on decel and the shop didn't tell me that Richmond has a break-in procedure for new gears. They recommend driving 10 miles and then letting gears cool for 30 min then driving 10mi., cool another 30min and again (I think it was 3 heat/cool cycles). I didn't know this and drove the car home 60mi at freeway speeds. The 2nd set I did this and haven't had any probs. I also had a specialty shop (tranny/driveline shop managed by the uncle of a friend) install 'em.

I also have a very hard shifting kit in my tranny and the poor setup on the 1st set of gears with improper break-in sheared of 4 teeth on the ring gear on a 1/2 throttle 1-2 shift on Nitto 315 DRs on an 80* day.

 

The shop told me about the break-in. I did that... I hope my gears last longer than a year! I plan on getting some 555Rs this summer. Thanks for the reply...

 

No prob. I should tell ya that the gears broke very soon after the switch to Nitto 555r DRs and the weather warmed up enough for good street traction (60*+). I'm saving for a 12-bolt