Every time I turn, i hear a clink clunk, shift, shift, and a little grinding. It only happens at low speeds, like in parking lots and in driveways whenever i back up or go forward while turning. I have a 2.73 rear end with posi. Could it possibly be the posi just shifting back there? Should I be worried about anything? Could it be the fluid in the differential? Should I check the fluid? If so , how? Any ideas on what this is???

 

Sounds like you need a bottle of posi additive. Pretty common... people change the fluid, and don't realize that even though the new bottle says "for limited slip differentials", it still needs the additive.

 

Go to GM and get a bottle of there Posi additive. I would almost guarantee that this takes care of your problem. It cost about $6 if I remember right. Only use the GM stuff other additives don't work as good.

 

yeah make sure that posi rear end has the right fluid and additive..

 

ok, thanx for the responses, but where do you put the additive in at. Obviously i know that it goes in the rear end, but where amongst the rear end?

 

If you look on the center section of the rear end, about half way up from the bottom (pass. side) you will see a square drive plug (like a pipe plug). A 3/8 drive rachet will fit right in to the square hole. Loosen it, To check your fluid you should be able to put a finger in the hole and feel that the oil level is just under the bottom of the hole. You add and check your fluid level through the same hole.

 

thanks man, appreciate it

 

Also, i forgot to ask, how do you know if it is time for an oil change in the rear end? Does it need to be a certain color, or dirty perhaps? And if i was to change it, how do u drain it?

 

anybody.....?

 

No problem with the help, Well I am not sure on the exact milage interval in which the oil needs to be changed, But if you haven't done it and don't know when it was done last it would be a good time to change it. And why add new additive to old fluid. This is often neglected maitenance item, so I am sure you will probably not have to do it again. Its not hard to do, you will have to get a new cover gasket or some RTV. You have to pull the actual cover off of the rear. leave a couple bolts in though so when you pry the cover off you dont make a huge mess. Let all of the fluid drain out, put the cover back on, pull the plug in the side of the case, and put new fluid and additive in. This is much easier if you buy a hand pump to pump the fluid in, there isnt a lot of room to simply pour it in. fill it until it just reaches the bottom of the fill hole. Thats it!

 

thanks man, i dont know when it was changed last so that sounds like a good thanksgiving break project. are there any brands that you recommend for the oil? i will be stopping by GM this friday to pick up some additive. should i get the oil from them also, or do u think another brand is just as good for less money?

 

I have valvoline synthetic blend in mine now it works fine. I would just pick up the fluid at a parts store. I dont know how much it runs at the dealer. I would just try to stay with a name brand stuff and not some cheap parts store brand.