What is a good brand of grease to use in our differential. I was using a limited slip grease, but someone said to use a limited slip grease, AND an additive. What do you guys use????

 

Mobil1 or Castrol Syntech diff oil is good parts store oil.I've used pleanty of both. RoyalPurple has several flavors that work excellent as well. All should be GL5/6 for limited slip use. A tube of friction modifier is easy to find at the parts store or you may purchase it from GM/Ford. You really don't want to run without it because the clutches can really chatter at slow speed around corners and parking.

 

How often do you replace yours. A certain mileage or time frame??

 

I think 30k miles is the recommended timeframe, at least from the Haynes manual, I'm not sure though. If you get an aftermarket cover it's easier than changing the engine oil, so no reason not to do it often. I just use Coastal 80/90 (comes in gallons) and your basic limited slip additive from advance auto. Of course, my theory is that since my gears are more likely to break teeth than wear too quickly, I'll save my money. I still use synthetic on the engine, though, since LT1s blowing rod bearings seems fairly likely for us folks that are a little tough on our rides.

 

lucas gear oil and gm limited slip additive

 

Where do you buy the gm limited slip additive?? Do you have to go to a dealer for that?

 

No, your local parts store should have some limited slip additive. When I changed my rear-end grease, I went with Wolfs Head brand. So far all has been great, and that was 20-30K miles ago.

 

Thanks guys, I might try that wolfs head oil and get some additive. Hopefully that will take care of my binding and chattering problem when I turn.

 

Mine was binding/chattering too, and that fixed it.