What Type of Rear Axle Oil & Additive for my Sure Grip Dana 60

[RT70]

I'm not only new to this forum, I also have purchased my long awaited (46 years) mopar, and have many questions. I have a 1970 Coronet R/T with a Dana 60, 9 3/4 inch, and 3.55 gears, the 4.10 gears are in the trunk. The R/T did not come with maintenance records, so I'm not taking anything for granted and changing all the fluids, filters, belts, hoses, etc. Nothing like having a power steering belt brake 50 miles from home! Now comes my first (of many) question. I have read much on this forum and the internet regarding rear axle oils and additives. I'm more confused now than before I started reading. Can someone simplify for me what rear end oil and additive that I should use. I believe my rear axle is referred to as a "sure grip", thanks, Richard

 

[Northern Runner]

Any gear oil will work really, I put 80W-90 in my 8 3/4 but some people like some different viscosity fluids like 75W-140. All in all as long as the diff has fluid it will be happy. As for the additive you can get it at any parts store, just look for the good names or head over to the dealership and pick some up. You might pay a little more there, but at least where I go, the guys have some older Mopars and already will know what you will need.
Have fun with that car, it will definitely stand out at all the cruise ins and car shows.

 

[hashmaker]

With a Dana 60 your ratio would be 3:54 to be specific, the Chrysler 8 3/4 was an actual 3:55. The Dana use two posi carriers, the better was called "power lok" the other was a "trac lok" which are not known for holding up well. The name sure grip was used with the 8 3/4 rear ends. I have been told many times by my differential guy that Ford's posi additive is the best although many others seem to work fine as well. You can tell a power lok carrier by the split it has where the two halves bolt together. The trac lok is all one piece.

 

[5.7 hemi]

Use the Ford additive, its hands down the best.

 

[RT70]

With a Dana 60 your ratio would be 3:54 to be specific, the Chrysler 8 3/4 was an actual 3:55. The Dana use two posi carriers, the better was called "power lok" the other was a "trac lok" which are not known for holding up well. The name sure grip was used with the 8 3/4 rear ends. I have been told many times by my differential guy that Ford's posi additive is the best although many others seem to work fine as well. You can tell a power lok carrier by the split it has where the two halves bolt together. The trac lok is all one piece.

Any gear oil will work really, I put 80W-90 in my 8 3/4 but some people like some different viscosity fluids like 75W-140. All in all as long as the diff has fluid it will be happy. As for the additive you can get it at any parts store, just look for the good names or head over to the dealership and pick some up. You might pay a little more there, but at least where I go, the guys have some older Mopars and already will know what you will need.
Have fun with that car, it will definitely stand out at all the cruise ins and car shows.

I appreciate the information as I'm on my first Mopar, thanks, Richard

 

[RT70]

With a Dana 60 your ratio would be 3:54 to be specific, the Chrysler 8 3/4 was an actual 3:55. The Dana use two posi carriers, the better was called "power lok" the other was a "trac lok" which are not known for holding up well. The name sure grip was used with the 8 3/4 rear ends. I have been told many times by my differential guy that Ford's posi additive is the best although many others seem to work fine as well. You can tell a power lok carrier by the split it has where the two halves bolt together. The trac lok is all one piece.

Thanks, the name "sure-grip" was used with the "8 3/4" rear ends, was there a specific name used with the "9 3/4" rear ends? I'm assuming I have a "9 3/4" rear end as it matched the picture on page 0-7 of the 1970 Dodge Coronet Service Manual. Wasn't sure on the rear ratio, as I used the old method (to get it close) of chalking the tire and driveshaft and then rotating the tire and counting the revolutions on the driveshaft. In 1970 could a Coronet R/T come with either a "power lok" or a "trac lok"? Thanks for all the info, Richard

 

[RT70]

Use the Ford additive, its hands down the best.

On the ford additive, is that a dealer item or any parts store? Can you use the Ford additive on any Chrysler positraction rear end? Thanks, Richard

 

[5.7 hemi]

At the Ford dealer and yes, you can use on a Mopar sure grip.

 

[Cranky]

Never ever found a Trac Loc in an older car or truck. My 2000 Durango has one in it's 9 1/4 but but the TL was installed in later model Dana 60's in trucks. The only type limited slip that I've ever seen in the older D 60's were Power Loks. Not sure what the parts houses carry but I've been using STP in my Durango Track Lok for the past 50k miles after the additive from the dealer didn't stop it from chattering. It's been just fine since...and the name SureGrip was used across the board for all of Chrysler's limited slip units. Both the Borg Warner Spin Resistant (cone units) and the Power Loks (clutch type) were called SG's.

 

[RT70]

Never ever found a Trac Loc in an older car or truck. My 2000 Durango has one in it's 9 1/4 but but the TL was installed in later model Dana 60's in trucks. The only type limited slip that I've ever seen in the older D 60's were Power Loks. Not sure what the parts houses carry but I've been using STP in my Durango Track Lok for the past 50k miles after the additive from the dealer didn't stop it from chattering. It's been just fine since...and the name SureGrip was used across the board for all of Chrysler's limited slip units. Both the Borg Warner Spin Resistant (cone units) and the Power Loks (clutch type) were called SG's.

I haven't noticed any chattering in the R/T so far. I jacked up the rear of the car, and rotated the tires. Both tires rotate in the same direction. The 1970 Service Manual says that I have a Sure Grip if that occurs. Since the car didn't come with any maintenance records I needed to know what oil and additive to use. I'm a few levels below all you knowledgable Mopar folks on exactly what I have for a rear end??? Thanks for helping, Richard

 

[PurpleBeeper]

Some gear lubes come with "positraction additive" already in them or you can buy it separately from auto parts stores (Trans X is the brand at Autozone I believe). I suggest you get a factory owner's manual which has all the fluid recommendations off of Ebay or somewhere like that. If you do your own work, you might consider a digital reproduction of the factory service manual too.

 

[RT70]

Some gear lubes come with "positraction additive" already in them or you can buy it separately from auto parts stores (Trans X is the brand at Autozone I believe). I suggest you get a factory owner's manual which has all the fluid recommendations off of Ebay or somewhere like that. If you do your own work, you might consider a digital reproduction of the factory service manual too.

Thanks, yes I have the 1970 Dodge Coronet Service Manual from Chrysler Corporation. It does have the recommended lubrications listed, however they are PN numbers from 46 years ago. I'd rather use what you "Mopar Experts" recommend as you folks have put a lot of miles on these rear ends, Richard

 

[Cranky]

Once you drain the old fluid, you'll get the chance to take a good look at the internals when the rear cover is off and can confirm it's indeed a SureGrip. It's only happened one time in my life (I'm 65...damn....I'm old) but a car that I thought had a SureGrip in it turned out to be rusted up enough on the inside that it locked the spiders which made both wheels turn together in the same direction. It has an open diff in it. Also, there are some people out there that do weld up the spiders to make it a locked diff. Another thing you can do to 'test' the integrity of the limited slip unit is to put one tire on the ground and with other off the ground, try and turn it. Make sure the trans is in neutral. You'll have to grunt but if it turns just by trying to rotate it by hand, it's weak and will need to have new clutches installed. It can be driven that way but just don't hammer it trying to make it double track.

 

[440+6]

This is what Brewers sells for additive, you can buy it at any mopar dealer also.

http://www.ebay.com/itm/Dodge-Jeep-...Modifier-Differential-Mopar-Oem-/391637524207

 

[khryslerkid]

What do you add the additive to?

 

[5.7 hemi]

The diff fluid.

 

[khryslerkid]

The diff fluid.

What's the recommended diff fluid?

 

[Cranky]

What's the recommended diff fluid?

As stated in post #2.....and I agree....

"Any gear oil will work really, I put 80W-90 in my 8 3/4 but some people like some different viscosity fluids like 75W-140. All in all as long as the diff has fluid it will be happy. As for the additive you can get it at any parts store, just look for the good names or head over to the dealership and pick some up. You might pay a little more there, but at least where I go, the guys have some older Mopars and already will know what you will need.
Have fun with that car, it will definitely stand out at all the cruise ins and car shows."

Also, that is the additive I used in my Durango and it didn't seem to help. It might work in the older stuff but it sure didn't help with the Track Lok...

 

[5.7 hemi]

Use what you like, but if you have a clutch style sure grip, I'd stay away from the synthetic stuff. That's my opinion, others may agree/disagree.

 

[RT70]

Once you drain the old fluid, you'll get the chance to take a good look at the internals when the rear cover is off and can confirm it's indeed a SureGrip. It's only happened one time in my life (I'm 65...damn....I'm old) but a car that I thought had a SureGrip in it turned out to be rusted up enough on the inside that it locked the spiders which made both wheels turn together in the same direction. It has an open diff in it. Also, there are some people out there that do weld up the spiders to make it a locked diff. Another thing you can do to 'test' the integrity of the limited slip unit is to put one tire on the ground and with other off the ground, try and turn it. Make sure the trans is in neutral. You'll have to grunt but if it turns just by trying to rotate it by hand, it's weak and will need to have new clutches installed. It can be driven that way but just don't hammer it trying to make it double track.

I'm also 65, and hoping I'm not over the hill yet!! I'll know a lot more when I pull the cover and drain the rear axle, thanks for your experiences. I'll do as you recommend on that test procedure, Richard