Chatter/Shudder/Vibration

[PGDimpala]

Hey,

Just got back from the woodward dream cruise, and have noticed a slight vibration/chatter feeling. Happens especially on left turns. Seems to be only noticeable when going very slow, and from what i can tell is not exhaust vibration b/c i can hear the right wheel shuddering.

I put a new eaton posi and gears in about 2 months ago, put in 2 quarts of valvoline gear oil and 2 bottles of GM additive. Is it possible that it already needs a fluid change? Does breaking the gears in dramatically reduce the life of the first fluid fill?

I already have 2 more quarts of fluid and 2 more bottles of additive so i am going to change the fluid this weekend, was really just interested in knowing if the posi can chatter after awhile even tho i did a proper fluid fill.

Going to woodward was the first major drive, bout 3 hours each way.

Thanks, Paul.

[Buffman]

depending on how many miles you've put on the new gears it may be time for a change. There really is no gear break in, but for safe keeping I always changed the oil in rear ends after gear and posi swaps after 500 miles.

[PGDimpala]

So, its been a couple weeks since i changed the fluid. I put in 2 and a bit quarts of valvoline gear lube and 2 bottles of additive. Did about 8-12 figure 8's in a parking lot. Fixed the chattering, been silent for weeks around town driving....GREAT.

unfortunately its chattering/shuddering again on very slow turns. It wasnt doing it until after i took it on a one hour highway drive. I am thinking the straight highway speed driving is causing the clutch plates to not be properly lubricated, or otherwise unlubricating the clutches. Possible?? I can't imagine it needs a fluid change again i have barely put on 500 miles since the last change. Probably only 200 around town and 150 on the highway since the change. When it has fresh lube, it works great, no noise no chatter and both wheels do the business, aka lay the rubber. Also the gears i did myself, but they seem to work beautifully, and are silent. So i dont imagine it has anything to do with the gears. Just the eatons clutch's.

Anyone with an eaton have any advice, or have experience with the same problems? Should i use three bottles of additive?? Should i not change the fluid, but do a lot of figure 8's to REWORK the lube back into the clutches?

Thanks, Paul

[PJ Gross]

I have about 150,000 miles on my 400lb eaton posi. No chatter, no anything. Don't remember the brand, but DTS where I bought the posi said to use dino 75-140 weight with 2 bottles of GM slip additive. I've only changed the fluid out once, so I'm sure I'm due again and I'd be interested in options.

In my CTS-V I'm going to try Red Line shockproof in the light and heavy blended with the slip additive, but I believe the V comes with synthetic already.

Not sure what advice to give, just giving you my experience.

-PJ