430 rear differential 'chatter'/grabbing. help

New to Ferrari. Purchased this beautiful 2006 F430 a month ago. 8400 miles. Algar did PPI which seemed pretty thorough.

When in 1st gear if I turn wheel all the way to one side or the other while maneuvering in a parking lot at low speed I'll hear some chatter at rear and can feel it as well. Quickly grabs and lets go, repeating quickly. Feels almost like recently washed and brakes rusted up (grabby) but more so as that goes away within feet of driving. Never an issue going straight at any speed. May be happening in turns at speed but I can't hear it or feel it. Took the car to Maserati dealer nearby who said it's in the differential best they could tell but they don't have the equipment/electronics to fully test. Said not likely bad solenoid as no lights are coming on to say there is a problem. Any thoughts on this?

Wish there were somewhere highly qualified in Cincinnati, maybe there is and I'm not aware.

I've been referred to RBC (could be off a letter) as well as Evans both in columbus. Don't mind going to MAG. Just want an extremely knowledgeable, trustworthy tech on the job. Not getting raped would be nice too. Suggestions?

 

NJB Westerfield ne of Columbus. Might just need new correct fluids.

 

Carl- Might be as simple as needing a little limited slip additive. A very little. Start with an ounce and increase until the sound goes away. Or switch to Valvoline Synthetic 75W-90, which has cured the chattering problem on a few Ferraris. Use it in mine, no additive needed.

 

Thanks guys. I'll look into the Synthetic. Not sure if this is something I can do on my own or suggest to repair place. Did about 100 tight turns this morning in a parking lot. Tried in all positions from snow setting to turning off the aided driving with dial on steering wheel. Didn't notice the issue with everything turned off but it's not so intrusive that easily noticed at all times. I do wonder if turning dial on wheel to off (I think it's CST) turns off the rear diff management and should remove the problem at least while all the aides are off.

 

+1

My thoughts also. Wonder if the wrong oil was put in last time causing this to chatter now.

 

Can I assume that a service bay is needed to add the limited slip additive or can one do this in their garage by jacking up each corner and putting wood under each tire to get 6 or 8" off the ground? I'm assuming it's not easily accessed from top side.

 

Remove the diffuser and you have access. you'll need a 12mm allen wrench to remove the dipstick. It will likely be very tight.

The car pictured has Capristo exhaust brackets installed. If yours is stock, you will have a few more things in your way.
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On lesser cars this is often a bad CV joint.

 

added about 2 or 3 oz of differential additive recommended by Algar. Will see if that solves it. Algar mentioned about half the 430s that pass thru them have this issue and it's resolved with the additive. Interesting. Will report back after driving.

 

How did you go Carl? Does it seem better now?

 

It does seem better now. I've not heard any more chatter. Thanks guys! I used Posi-Trac limited slip gear oil additive by Trans-x in 7 oz tube. Cost $10 at Advanced Auto Parts store.

 

Back it up with some circle work figure of eights slow and tight in a car park. That will give the LSD a workout.

 

Not too good for the clutch and can just as easily be done in 1st.

 

Good to hear mate, thanks for letting us know.