Difference between a Sure Grip and a Dana Power-Lok

[Red63440]

Just need some info on the difference between them, pluses and negatives.
Thanks!

 

[Red63440]

https://pdf4pro.com/cdn/mopar-8-75-rear-differential-information-7c989.pdf

 

[Cojohnso1]

That's a bit of a tough direct comparison question? They are different designs. But in overall performance? The Dana is bigger and stronger. (But also heavier. Including rotating weight) if you are looking at a mild/mid street build? An 8 3/4" sure grip can easily handle. No sense dragging extra weight. Especially with an automatic transmission. The reason B-bodies with big block 4-speeds got the Dana? Was not so much about a 4-speed adding more stress. But more about driver habits. I guess us 4-speed guys are tougher on parts? Say it ain't so? Lol.

 

[blue69runner]

This could be true on the four speed guy's. I try to shift at around 2500 RPM. But you know I still spin the tires just a bit when taking off. LOL.

 

[Kern Dog]

The term "Sure Grip" is a brand name that the Chrysler Corporation used to describe their limited slip differential. General Motors had brand names for theirs, Ford and AMC did too.
You could have a clutch or cone type and the term Sure Grip would still apply.
My experience.....Many called the 8 3/4" cone type limited slip the "Auburn" unit since they were known for producing those. The Dana Power Lock uses replaceable clutch discs to facilitate the limited slip action and is often preferred since it is rebuildable.

 

[Red63440]

That's a bit of a tough direct comparison question? They are different designs. But in overall performance? The Dana is bigger and stronger. (But also heavier. Including rotating weight) if you are looking at a mild/mid street build? An 8 3/4" sure grip can easily handle. No sense dragging extra weight. Especially with an automatic transmission. The reason B-bodies with big block 4-speeds got the Dana? Was not so much about a 4-speed adding more stress. But more about driver habits. I guess us 4-speed guys are tougher on parts? Say it ain't so? Lol.

Dana made the 8 3/4” Sure Grip for MoPar based on what is in the link. We aren’t talking a Dana rear end, just the 8 3/4” Sure Grip unit.

 

[Cojohnso1]

Dana made the 8 3/4” Sure Grip for MoPar based on what is in the link. We aren’t talking a Dana rear end, just the 8 3/4” Sure Grip unit.

I like my 8 3/4" inch in my Drag race 451 Duster. It's upgradable to 35 spline. (But with spool that's not as pretty on the street) Plenty of aftermarket axles. Nice bang for the buck unit. So far? I'm more of a problem than either my 8 3/4 or Dana rears. Lol. But also keep in mind. 8 3/4" rears are easier to change gears. Hell with the right setup? You can have center carriages with different gear sets ready like the Ford 9". Dana? Unless you are a ninja with one of them? It's an all day job.

 

[Cranky]

Dana made the 8 3/4” Sure Grip for MoPar based on what is in the link. We aren’t talking a Dana rear end, just the 8 3/4” Sure Grip unit.

Both are Sure Grips.....but each is a different design. The early ones up to early 68 were clutch type and everything after that was cone units. Both work pretty good but the clutch unit has replacement parts and the cone unit does not. But....if the cone stops pulling both wheels on a burnout and a person stops trying to make it lock up, it can usually be machined to work again. Been fixing them for well over 30 years....

 

[Cojohnso1]

Both are Sure Grips.....but each is a different design. The early ones up to early 68 were clutch type and everything after that was cone units. Both work pretty good but the clutch unit has replacement parts and the cone unit does not. But....if the cone stops pulling both wheels on a burnout and a person stops trying to make it lock up, it can usually be machined to work again. Been fixing them for well over 30 years....

30 years? I would say that qualities you as a ninja.

 

[Red63440]

I was just able to pick up a 3.23 clutch style Dana Power Lock for the Fury. It’s a 742 small yoke case which will be perfect for street use. Just finishing up the 383 so it turned up just at the right time.

 

[Cranky]

30 years? I would say that qualities you as a ninja.

My introduction to gear replacement was in 84 but my first pig swap was in 71. Both were learning experiences. After 84 I started hitting the pick and pull yards and it went down hill from there and that's when you could pick up an 8 3/4 3rd member for 39 bucks! Recently got done doing a Dana 60 from hell. The housing came from Venezuela and that should have been my clue to leave it be!! I've rebuilt and shortened several over the years but this one was one was.....well, from hell! lol

 

[Cojohnso1]

My introduction to gear replacement was in 84 but my first pig swap was in 71. Both were learning experiences. After 84 I started hitting the pick and pull yards and it went down hill from there and that's when you could pick up an 8 3/4 3rd member for 39 bucks! Recently got done doing a Dana 60 from hell. The housing came from Venezuela and that should have been my clue to leave it be!! I've rebuilt and shortened several over the years but this one was one was.....well, from hell! lol

Lol. Ninja skills tested? Remember. There is no bad parts. Just bad people, in bad companies with bad quality assurance and bad work ethics.

 

[Red63440]

In 1970 I went to my local scrap yard and picked up a 68 340 with the 727TF along with a complete rear end with 3.91’s out of a Dart for $325.00. I installed it in my 66 Plymouth Valiant and everything bolted right in, I had a ball with that car!!

 

[Cojohnso1]

In 1970 I went to my local scrap yard and picked up a 68 340 with the 727TF along with a complete rear end with 3.91’s out of a Dart for $325.00. I installed it in my 66 Plymouth Valiant and everything bolted right in, I had a ball with that car!!

Nothing sweeter than a scrap yard pull and fix. A lot tougher these days. But it still happens.

 

[Red63440]

Nothing sweeter than a scrap yard pull and fix. A lot tougher these days. But it still happens.

Not for those prices

 

[GrabberOrange69]

https://pdf4pro.com/cdn/mopar-8-75-rear-differential-information-7c989.pdf

Fantastic info, thanks!

 

[Cojohnso1]

Not for those prices

True. Those are days gone by

 

[Red63440]

Fantastic info, thanks!

That info was provided by “rarefish”.

 

[blue69runner]

If you are racing larger axels are a must. When coming off the line one time shifted to second and noticed to my left a tire going by me. Said to my self who's tire is that. Then the rear of the car dropped to the asphalt. Larger U joint's also. The hole drive line need's to be up graded. Have a open diff. now. Have a cone 489 to go into the car. Only to have both wheel's pulling at the same time. Figure better traction is safer. Good luck on the quest.

 

[440 Charger]

The term "Sure Grip" is a brand name that the Chrysler Corporation used to describe their limited slip differential. General Motors had brand names for theirs, Ford and AMC did too.
You could have a clutch or cone type and the term Sure Grip would still apply.
My experience.....Many called the 8 3/4" cone type limited slip the "Auburn" unit since they were known for producing those. The Dana Power Lock uses replaceable clutch discs to facilitate the limited slip action and is often preferred since it is rebuildable.

Lets be all sure of the grip.