For a shop in metro Austin, Texas to do the following on a 1992 Convertible with auto trans and 2.73 factory rear axle ratio:

- Provide 3.54 ring & pinion (U.S. made Richmond pn 49-0143-1 will work with the 2,73 carrier in the D36 housing: $340.00 from Jegs, retail)
- Provide ring pinion install kit
- Labor to chnage 2.73 gear set to 3.54 gear set properly
- Parts & labor to correct speedo gears in auto trans

What is the price I should expect?

Jim G

 

Jim,
I'm not a complete expert in this subject matter, but will say this about the speedometer. The VSS send a signal to the ECM, and then it outputs to the instrument cluster. I believe there's a buffer there that converts the signal for the speedometer. My point is that this may be a bit complicated for a rearend shop. I think you should contact www.jagsthatrun.com for further advice.

http://www.jagsthatrun.com/V8-chapte...ed-Sensors.pdf

See page 4

 

A gear swap should be no more than 4 hours of labor. I'm gonna guess that the labor in Austin is about the same as the labor in San Antonio.....approximately $75 an hour.

So.....labor, roughly $300.

Install kit about $80.....maybe a bit less.

KW

 

Thanks for drawing my attention to this. It turns out that page 12-18 is more relevant for the 700R transmission I have (not 4L60E). For $49, Stealth Conversion will provide the required gear set for the tranny tailshaft if you simply give them the new axle ratio you are installing.

Jim G

 

This is helpful, Kevin! The reason I asked is that I have had rear axle ratio changes done in the past, and the whole job including parts and labor was under $1000.

The local Corvette shop, admittedly known for both its quality and high prices, said $1700 range!

Jim G

 

Good grief !!!

Stop by and talk to mechanics at a local truck stop.....you'll likely get a MUCH better deal!

KW

 

In fairness, ding the gear swap on an IRS setup like the Corvette is probably a little more time, as I imagine some stuff outside the pumpkin gets in the way. But, $1700 seems REALLY a stretch!

Jim G

 

Flat rate time on a rear gear change for a vert is 9.7 hrs.

 

So, at $75 per hour shop rate, that would be almost $750.

Even that rate, plus the gear set, install kit, and speedo correction kit, comes to $1250, not $1700. Even at $100 per hour, it's still $1500, not $1700. Interesting.

Jim G

 

Quote:

Originally Posted by blackbear bob

Flat rate time on a rear gear change for a vert is 9.7 hrs.

In all honestly, 1700 is probably what you would pay in the area up here. Most shops such as Zip will charge 595 for just the rebuild and 959 for rebuild with gear change. http://www.zip-corvette.com/GroupDetails/SubGroupResults.aspx?gid={63786068-8268-4dad-aebe-75036f273cab}&SearchType=_GROUP_SEARCH&G roupName=Differentials&
Keep in mind, these prices are assuming you pull it and bring it to them. This does not include, oil, sealer, or R&R. Neither does it include things such as likely breaking the exhaust studs separating the exhaust if its never been down before.
The 92 needs the speedo gears changed. Talk to WVZR1 and he could give you exact part numbers. They are cheap and easy to do while the driveshaft and c beam are out of the car.
Good luck, and fwiw, that is one of the best mods you can do to a LT1.

 

Forgive my ignorance: so the driveshaft and c beam both have to come out to make the swap?

And thanks for the headsup on WVZR1 potentially being able to help with the part numebr for the speedo gears. I have alreayd elarned via other psotings that he is an absolute fountain of experience, and also very generous in sharing his knowledge.

Jim G

 

I'd like to see anyone drop the exhaust, rear suspension, batwing and carrier, remove the old gearset, rebuild and reset new gears and assemble all above in 4 hours.

 

I was quoted $1800 for the exact same thing here in Orlando. 3:54 gear into an auto 95 for parts, labor, speedo calibration the whole deal. That is more than what I am willing to pay currently $1000-1200 seems reasonable to me from a reputable shop and the peace of mind knowing it will be done right.

 

Thanks for clarifying what all is required to be done. It makes things a lot clearer. The gear set $345 + a GOOD install kit with EVERYthing $125 + speed gears $50 = $520 (at retail, not shop pricing). 10 hours at $75 (I think that's the local rate here in Austin, Texas, but am open to correction) is $750. So, it would seem that a price of $1270 might be reasonably generous.

The Richmond gear set is U.S. made versus foreign, and Richmond themselves told me this morning that yes, it will work specifically with the Corvette D36 with the carrier currently holding the 2.73 gear set.

The conbination of a quality gear set and a skilled installer should make for a nice, quiet setup.

The 3.54 ratio will yield barely over 2000 rpm at 60 mph in OD, and 1st gear is still good to 40 mph. Available horsepower at 60 mph in OD jumps from about 75 to over 100. The 0 to 60 time drops 4/10ths of a second per my vehicle modeling software. While I never race or anything like that, these numbers tell me the car will feel VERY much more nimble.

So, I have the info I need. Now I just need to find the right installer.

I have 2 local shops in mind, both of whom I have had experience with, and both of whom have done Corvettes and know what they are doing. The owners of both are friends. One has very low overhead (outside the city), and so I'll give him the first shot.

Jim G

 

Or you could do it the less expensive way like I did. Pick up a used pumpkin and do it yourself. If you can turn a wrench it's not that hard, just takes time and patience.

 

 

Your '95 is just a little easier to accomplish than the OP's '92 in so much as you can calibrate the speedometer/odometer in the "tune". The '92 requires a drive gear, a driven gear and a VSS to do it correctly with "mechanical operation". The VSS has been "short-cutted" by some and most are happy with what they did, I've never done it or suggested it but the last fellow that elected to do it, did it as I suggested and who knows how long it will last. I know no one with 50K miles on one that can attest to the durability of the short-cut.

The OP does NOT need any type of buffer nor does he need the services of "JagsThatRun" (good guys though). Drive and driven gears aren't as easy to come by these days. The vendors that everyone used to rely on don't have stock of most and there will likely not be any more. I have I think one set for a 3.54 left. If that's not an option I'd consider a GPS triggered system by AutoMeter over the DRA's from other vendors. I spoke with them several months ago and it seems they feel their system is compatible and probably not difficult to wire. I have never used one.

I would think an offering of $1700 reasonable but I can't see that happening for the OP if the shop elected to or had to go to the AutoMeter or a DRA from someone. Set-up, installed and warrantied I don't believe it unreasonable. I'd expect the exhaust hardware and miscellaneous NOT to be included.

Another thing that needs considered here is if you start directing a shop to a "brand" or a buy from "here or there" you're likely to be out the warranty. They installed what you asked be installed, if you weren't happy or if there were issues it could get interesting.

 

My wife and I currently live in a rented cabin, with no garage. The driveway is gravel and caliche, and has a 7 percent slope. NOT conducive to safe OR clean DIY.

Besides, my 1992 convertible has only 11,000 miles on it - 1600 of those miles added within the past 6 weeks since I bought it. The Carfax and Autocheck reports on it confirmed a steady 300 to 400 miles per year "exercising it" as the only usage. That's a basically brand new axle!! No way I want to trade that for an axle of indeterminable history or usage!

Jim G

 

That being said I believe I'd just adapt my driving style and learn to enjoy the 2.73 gear OR buy another D36 and have that one built. I've got a D36 housing that you could buy and build and save the 11K mile rear. The 11K rear and the 2.73 certainly has "value" - the used 2.73 gears regardless of miles won't bring $50 unless someone really needed.

Buy a carrier, the gears and if you wanted you could use your short axles from the 2.73 and not sacrifice any of it's value.

 

WVZR1, I wasn't thinking "value". I was thinking "reliability" and known history. I KNOW my current axle and its components are almost new and have never been abused. THAT's why I want to keep it.

Someone has suggested that you would know what speedo gears I would need for this swap from 2.73 to 3.54. Do you?

Jim G