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During all my mess with the 6 link stuff...I replaced the diff fluid with Redline Synthetic 75w-90. According to Redline I do not need the Posi Additive because this stuff is synthetic and is already formulated to be used with Posi. I read that Posi Additive is to reduce the clanking noise on the posi unit and adding too much can cause the clutches to slip which I think I read directly from the posi additive bottle. At the time when the diff was rebuilt the builder put in the Posi Additive. I had mentioned to him initially after I got the car back about the clanking sound and he added MORE and told me to drive around in a figure 8. Well...finally about 2,000 miles ago it stopped clanking. I do not hear the posi noise now either with the new Redline fluid.

So my questions are...

When do I need to add the posi additive....
A. only when I hear it making noise?
or
B. its mandatory to be added under all circumstances?

Second question is does adding too much cause clutch slippage?

Thanks....
 

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Thats a good question. I was going to do the same with my diff except use Mobil 1 75/90. It says it works fine with limited slip & positraction as is.

Whats the scoop on this????????? :crazy: Comments anyone!!!!!

:cheers:
 

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The final answer will have to come from a real expert, but my $.02 is that the additive needs to be used all the time- from brand new until the car won't move anymore. Whale oil is some slick stuff and keeps the clutches from eating themselves.


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The final answer will have to come from a real expert, but my $.02 is that the additive needs to be used all the time- from brand new until the car won't move anymore. Whale oil is some slick stuff and keeps the clutches from eating themselves.


:cheers:

Tim, they haven`t used whale oil for years (probably 20 years)...it`s all synthetic.
redvetracr

edit: more like 30 years!!
 

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HHmm, maybe they haven't used whale oil in that long, I figured they hadn't changed- the stuff still stinks. Maybe not quite as bad as it used to.

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a while back someone on the NCRS site made mention that some original whale oil additive sold on ebay for stupid money (sorry I don`t remember the price)...the parts guru Joe Lucia posted GM discontinued the whale oil in 1974 and someone else (maybe Duke Williams) went on to say that whale oil was an "organic material" and that after all these years it had most likely turned bad......
redvetracr
 

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If you don't have any hammering now you're ok. I've heard that story of too much causing slipage and never really bought it. You have a stock setup, clutches,plates,and springs.The reason it hammers is because the clutches can't slip in corners. Typically the stock set ups are all over the place. They may be loose may tight so the band aid approach for production line work was to add the plates and springs. To try and have someone tune a posi on a line would be too labor intensive.

Here is a new clutch pack I installed. There is not a lot of movement here. The plates in the pack have tabs that fit in the posi case.



Here is a solid clutch, this is the type you want to have in yours.




Here is the whole deal.






Hope this helps. If not hammering drive it. If the Gm additive doesn't work then the only thing you can do is to build a good one.
Good luck
 

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Hmmmm...a recall of that type should have had some mention on the web. I haven't found anything on numerous search engines. :crazy:
 
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