Open diff to Posi-Trac

[Corbin]

I am wanting to swap out the 3rd member for a Posi-Trac setup for the 8 inch rear end. Are there any other changes that are required if I simply put in a Posi-Trac 3rd member?

[Voodoofalcon]

As long as it's a 28 Spline carrier you shouldn't need to change anything. You will need to run a friction modifier in your oil.

[Luva65wagon]

Corbin,

If you are still shopping for one... I bought one off eBay after having installed one (a 9" version) in a 69 Mustang for a friend who purchased his from the same place. It was lower in cost from all the others I saw; plus you got to choose the ratio, and it shipped with the required friction modifier.

Of course I'm not where I can look up the seller info, but will look it up, if interested.

[Corbin]

Thank you Mike, I appreciate it.


Roger - Yes I am still looking for one. I wouldn't mind seeing what you have available. Please take your time, there is no rush. My plan for this week is to nail down a local engine builder for the stroker. I have it narrowed down to two shops and am going to visit one in Olympia today to see their layout and get a few questions answered.

[Voodoofalcon]

I bought my 9" parts from Quick Perormance , I had an issue with excess runout on the ring gear when I put it all together. They stood behind there parts and sent me another set of gears. Some good info on there sight as well

[Luva65wagon]

I got mine from this seller if I recall correctly:
https://m.ebay.com/itm/8-INCH-FORD-TRAC-LOC-REAR-END-MAVERICK-COMET-STREET-ROD-MUSTANG-POSI-550hp-9/223071905017?epid=1024622832&hash=item33f01f24f9%3Ag%3AxRMAAMXQ0pNQ9gEa&_pgn=1&_sacat=6028&_nkw=8+ford+rear+end&_from=R40&rt=nc

If that link doesn't work for some reason, the seller to search for on ebay is: tj1141

Can't remember exactly what I paid at this moment (need to be at home on my computer), but I think it's gone up a little since I got mine.

[Corbin]

Thank you Roger.

It blows me away how much money these posi units are going for. Guess I've been out of the game too long.

I did find a local seller that has one with a 3.00 gear for about half of the price of those on Ebay. All said and done, it may just be easier to buy a new one and bolt it up rather than buying a used setup, doing a gear swap and then install.