I’m getting ready to purchase a new third member for my 1969 Super Bee automatic with a 383. I’m ordering through Dr. Diff and I’m at the differential section. I’m not sure which of these I’m supposed to pick. I want a sure grip. I’m thinking the choice would be the 6 helical sure trac 2? Advice please. I have been emailing him as it sounds like he is super busy and not able to take phone calls currently.
Personally I wouldn’t use a spool on the street. With a spool you essentially have a solid axel with no differential.
The spool is cheaper in this instance because there is nothing to it; essentially just a solid steel collar that joins both axels together. The sure trac is quite a bit more complicated to make, thus more expensive. I personally have no personal experience with that exact unit, I just know that you need some sort of limited slip differential rather then a spool.
Dr. Diff is awesome in their awesomeness, by the way. I got my 489 case rebuild kit there. Many of the guys on this site buy there.
Truetrac for sure, I won't run anything else unless I need a locker..... screw clutches! Truetrac and plain Jane 80w90 gear oil, done!
That looks like options to the base configuration? What differential comes standard? Maybe the maybe the clutch type powr-loc ? I would call to see what options there are. On a street car you don't want a spool, but some type of limited slip or the sure-track? The helical Sure track can have different torque bias ratios built in. I'm curious what the torque bias ratio of the Dr. Diff Sure-Track is.
Pretty sure he doesn't do his own truetracs, just sells the Detroit units....at least that's how it was when I bought one of mine through him.
Dr Diff sure-trac is his own unit that he has built in bulk lots. Helical gear, but not the same as the truetrac.
