hey all, i just got my car back from the shop, i had a posi and 3.42 gear installed and man does it pull hard. I noticed a great improvement for 0-80. only complaint is the noise that it makes, makes alot of noise when i am coasting, but when i accelerate it goes away. Is this something that will go away when everything gets lubed good? If not how do i get rid of it? also the speedo is off by about 10 mph, i know i can get another speedo gear, where at and how much?

 

This really belongs here.

 

Sorry i thought about it after i posted.

 

Did you do a proper break in before getting on it? What you are describing is gear whinning... if you used Richmond gears, then that is normal.

 

i bought the posi unit off slp, and the ring and pinion off ebay, it oem for 98-02 f body. And i didnt know there was a break in period.

 

what is a good break in period for something like that?

I put a shift kit in and ran the car for 100+ miles before i got into it. What is a good distance to plan on for stuff like transmission mods and what not?

-chuck

 

http://www.precisiongear.com/pgtech_breakin.htm

All new ring & pinion sets require a brief break-in period in order to ensure long life and quiet operation. The following break-in procedure is recommended before applying a heavy load and/or constant usage.

1. Insure that the axle has been filled to the correct level with proper hypoid lubricant before driving the vehicle. The oil rating must be GL5 or higher.

2. Bring the axle to normal operating temperature by driving the vehicle (unloaded) for approximately 15 to 20 miles. Do not run full throttle accelerations or create any shock loads.

3. Let the axle assembly cool completely.

4. For the next 200 miles of operation, drive gently, without any heavy loads.

5. If trailer towing is intended, an additional cycle of 200 to 300 miles of break-in is required without the trailer. This is important! To properly break-in a new gear set, a minimum of 500 miles of driving is essential before towing.

 

Good to hear! I've got 3.42's as well. If the gears are used you shouldn't need to break them in though.

 

if you're getting noise while coasting and not on acceleration, i'd think the backlash isn't set properly. i'd suggest you take it back to the shop that set it up.

i did the exact same swap last fall. slp takeoff posi and used gear. mine doesn't make any noise at all.

there are two ways to go to get the speedo to work properly.

the correct sppedo gears for this application are available and cost less than 50 bucks, but you have to change both gears, so you have to drop the transmission or remove the tailshaft.

i took my car to a speedo shop. they installed an electronic box to correct it. it cost 200 bucks, but it'll be a simple matter to calibrate the speedo in the future when i change tire sizes, which i wouldn't be able to do with the stock gears. also, since i don't have the space or tools to drop the tranny, i would've spent about the same thing with the labor.

those 3.42s are awesome for these cars. i picked up 6 tenths in the 1/4 mile from the gears alone.

 

I have heard this before. Why is it that Richmond Gears are so loud? I had a set of Richmond 3:73s installed into my T/A and they quieted down to the point that there is no noise on or off the throttle, but just a little noise when maintaining speed.

 

From what I have heard from them: they make their gears specifically for strength, with noise being only a minor secondary concern. I am having my Moser 9" rebuild with Precision gears, which was reccomended by the shop I am using. I kinda ****ed this one up doing excessive speeds on the highway and blew the pinion seal, and a ruined the bearings in the rear before I got back to fix it. Since then it has gone form whinning, to incredibly loud whinning, to an obnoxious grinding sound. Not sure if this gonna hold up for the week, should have it in the shop by the weekend, but man is this a pain in the *** to drive with.