I have a 68 Camaro with a recently installed T-56 and professionally rebuilt 427. For some reason, I am hearing what I would describe as "chatter" from the tranny. After reading the other posts on chatter, I don't think it's the classic clutch chatter. When I push the clutch pedal in, it goes away completely. The sound has no affect on the car when I start from a stand still, or any shifting for that matter.

It's more of an anoyance than anything, but I would still like to fix the problem if possible. I was not real careful when I put the flywheel on the motor. There maybe some grease on it.

The clutch is a Centerforce Dual Friction. The bellhousing is a Weir custom.

Any idea's?
Thanks
Rick

The sound could be your throwout bearing not disengaging far enough and is lightly tapping the fingers on the diaphragm. Are you using a mechanical or hydraulic throwout?

Thanks for the reply, it's hydraulic. How would I fix or test that?

I'm not that well versed on hydraulic clutch setups. I found this, I hope it's helpful.
http://carbuff.homeip.net/weir.html

If you hear it in neutral with the clutch engaged (pedal up), the Viper guys call it "neutral gear rattle", and has been a common annoyance on the Viper for many years. The treatment that pretty much takes care of it on the Viper is to use Castrol "SynTorq" tranny fluid, which is also available at Dodge dealers in a Mopar-label container, specifically for the Viper. graemlins/thumbsup.gif

Thanks for the responses. I checked out the link and I don't think it's the same issue.

I will try the Castrol fluid and see if that helps.

Does anyone know the fluid capacity of the T-56? I saw somewhere that it was 2 quarts, but that seems like a pretty small amount. If thats the case, I may have over filled the tranny last time.

Thanks

The local Dodge dealer wants $21.75 per quart for the Castrol. It's sold under part number 4874459, with a Dodge name on the bottle. Does that price seem out of line? Maybe I can have my local auto supply shop special order it for me. I found out I need 4 quarts.

I found this on a Dodge Viper site, it sounds like my problem:
TSB# NO: 21-06-98
*PARTS REQUIRED:**

4 of #04874459 Transmission Lubricant, SAE 75W (MS-9070)(Quart)
1 of #04275086 Label, Authorized Modification


M/T - Gear Noise Explanation

NO: 21-06-98

GROUP: Transmission

DATE: Apr. 3, 1998

SUBJECT:
Neutral Gear Rattle With Clutch Engaged

THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 06-01-97 DATED MARCH 14, 1997, WHICH SHOULD BE NOTED IN THE 1997 TECHNICAL SERVICE BULLETIN MANUAL (PUBLICATION NO. 81-699-98004). THE PARTS AND REPAIR PROCEDURE HAVE BEEN CHANGED. ALL CHANGES ARE MARKED WITH **ASTERISKS**.

**MODELS:**
1994 - 1998 (SR) Viper

SYMPTOM/CONDITION:

A light chatter or rattling noise from the clutch housing or transmission area with the clutch engaged and the transmission in neutral. The noise will diminish with the clutch disengaged.

Clearances in the transmission gear teeth are incorporated into the design for component durability. There will always be a slight amount of gear mesh noise. No attempts should be made to disassemble the transmission for this condition.

WARNING :NO ATTEMPTS SHOULD BE MADE TO TIGHTEN THE CLEARANCES BETWEEN THE TRANSMISSION INTERNAL COMPONENTS.

NOTE : WHILE THIS REPAIR IS HELPFUL IN REDUCING NEUTRAL GEAR RATTLE, IT WILL NOT ELIMINATE IT. IN ADDITION, THE NEW FLUID WILL CAUSE SOME INCREASED SHIFTING EFFORT AT 20°F AND BELOW. THIS WILL CONTINUE UNTIL THE TRANSMISSION REACHES NORMAL OPERATING TEMPERATURES. PLEASE INFORM THE OWNER OF THIS POSSIBLE CONDITION BEFORE BEGINNING THE REPAIR.

**DIAGNOSIS:**

Road test the vehicle to warm the vehicle powertrain. Drive in 3rd to 5th gear to help bring the transmission to operating temperatures. Stop the vehicle and apply the parking brake. With the transmission in neutral and the engine running at idle, depress and release the clutch pedal. Listen for a chatter or rattling noise whenever the clutch pedal is released. If the noise is diminished when the clutch is depressed, proceed to the Repair Procedure.

*PARTS REQUIRED:**

4 of #04874459 Transmission Lubricant, SAE 75W (MS-9070) (Quart)
1 of #04275086 Label, Authorized Modification

**REPAIR PROCEDURE:**

This bulletin involves draining the transmission fluid and replacing it with a new lubricant.

1. Drain the transmission fluid by following the procedure in the Viper Service Manual (Publication 81-270-7150) page 21-3.



2. Type the necessary information into the Authorized Modification Label and attach the label near the VECI label.

POLICY: Reimbursable within the provisions of the warranty.

TIME ALLOWANCE:

**Labor Operation No: 21-00-10-95 0.4 Hrs.**

FAILURE CODE: P8 - New Part

[ 03-31-2003, 10:01 PM: Message edited by: rickmack ]

I changed the fluid tonight. I would say that it reduced the noise by about 3/4's. Thanks for the tip. By the way, it cost $90.00 to change to the MOPAR synthetic, but it's worth it.
Rick