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Looking for input on limited slip differential, 8 3/4 axle

Odmark91

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Hello. Im going to pull my diff to swap out the gears in my Polara, and im thinking about replacing my old cone type SureGrip with another carrier, but im not sure what to get.
It has a mild 505 Stroker with 589hp and 615lb/ft, 4 speed manual.

Are the Detroit Truetrac any good for the street? Or should i go for a clutch type? Or should i just keep the cone SureGrip until the axle blows and save my money to get a Dana 60?

Input appreciated.
 
Detroit truetrac is my recommendation...built my jeep axles with them and currently running one in my 68 coronet with 3.23 gears...my 70 dart still has the clutch sure grip in it. If I ever go through that one it'll get a truetrac.....they've changed since I've bought any, improved a bit I believe....Cass from Dr diff has a version of the that style diff too...
 
True trac is the Cadillac. Or imperial
 
Do you go to the track at times and run slicks or something sticky for traction? If so, it probably won't matter what type of limited slip unit you are running since you are taxing the 8 3/4 pretty hard with running that much power AND running a stick in a fairly heavy car. Anyways, the cone unit will probably hold up and what you'll blow will be the gear teeth in the 8 3/4. What generally happens to the cone (and even the clutch type) is that it wears down to the point that it won't make both wheels pull anymore and will turn into a 'one wheel peel' and then if you keep on 'trying' to make it it grab by trying harder, then it usually with do damage that's not worth repairing. But if you plan to never run anything more than street tires, things will most likely be ok with the 8 3/4.
 
To me the V-ramp Factory Dana/Chrysler clutch type Sure Grip is the best.It is rebuildable. Dr.Diff has the kits.
Right now I have the 8 3/4 True Trac in my car with 3.23.It works great. It is noisey at slow turning speeds and was annoying at first.
A common complaint. Lots of You Tube videos on the subject. Some say theirs make no noise,some do.My car is street only. When installed I used 75/90 gear oil (non additive type is recommended)
A switch to straight 140 gear oil quieted it down and I hardly notice it.
I agree with Cranky if the car is only for street and using street tires the 8 3/4 will last a lifetime.New gears new Sure Grip and you are set.
 
I used a nitro suregrip carrier
BIG MISTAKE!

325/50/15 nitto tires 4.30 gears and 4 speed. Went to trutrak. No issues yet.
 
Stripped the splines.
Did you do that within the years warranty period? Still should have never happened in the first place! Did you have aftermarket axles? I know those can vary in size a bit. Have a pair of Moser's in right now and they are really snug in the spool but don't know what brand the spool is. Also, they don't run true when in the lathe....
 
Investing more money in the 8.75 I wouldn't. You could buy a Strange Dana 60 then no worries. If you get the urge to put on sticky tires on you won't be thinking about busting the rear. Sell your 8.75 rather than wait for it to break. If rear breaks and it could cost you money to get the car home. Do you have a 23 or an 18 spline trans?
Liked Cranky's post #4.
 
Did you do that within the years warranty period? Still should have never happened in the first place! Did you have aftermarket axles? I know those can vary in size a bit. Have a pair of Moser's in right now and they are really snug in the spool but don't know what brand the spool is. Also, they don't run true when in the lathe....
Also if the installer isn't diligent in checking things properly, stripping splines off will happen if the axles are too short.
Have been a witness to this.
 
To me the V-ramp Factory Dana/Chrysler clutch type Sure Grip is the best.It is rebuildable. Dr.Diff has the kits.
Right now I have the 8 3/4 True Trac in my car with 3.23.It works great. It is noisey at slow turning speeds and was annoying at first.
A common complaint. Lots of You Tube videos on the subject. Some say theirs make no noise,some do.My car is street only. When installed I used 75/90 gear oil (non additive type is recommended)
A switch to straight 140 gear oil quieted it down and I hardly notice it.
I agree with Cranky if the car is only for street and using street tires the 8 3/4 will last a lifetime.New gears new Sure Grip and you are set.
Really? All 3 I installed were silent. El cheapo 75/90 gear oil. Sure it's the truetrac and not the gear setup?
 
As I said after a good warm up drive, at slow speeds turning you could hear the helical gears.
Not a problem just was annoying to me. Couldn't turn the radio up,don't have one.:lol:
Also could be the early ones. I believe I read that Dr.Diff stopped selling them because of complaints.Not saying I am correct on that.
Yes many that have them say they have no noise issues. I would not hesitate to buy one.
My favorite is the Factory Dana/Chrysler V-Ramp before they went to the cone clutch type.
 
Thanks for all the inputs! Since i mainly run street i think ill save my money for a D60 and keep the cone suregrip since its really nothing wrong with it.
 
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