Lower priced Power lok, sure grip units on Ebay.

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Was curious bout something.. i know like 742 and other cases use a different ring/pinion but they all use the same carrier?
Yes, I have Dana Power locks in 741, 742, and 489 cases.
I think the Dr. Diff ones are the same ones. But he changes a few things.
I know the cheap China ones I used before gave had not enough or to close on the clutches.
Kinda like cheap China heads. A guy can use out the box, but would check before use.
 
Personally, I wouldn't care. If they're backed by him, I'd trust it a lot more than anything sold by a no-name ebay seller.
I agree. My point was, that the ebay piece and Dr. Diff's piece are likely the same. Seems like I read somewhere Dr. Diff disassembles all of his checks for clearances and such and he may even modify them for stronger lockup.
 
I think I still have one here. Can take a few pics Thursday. After the storm is gone. It should be here in next few hours. So pics have to wait till Hurracane is gone.
 

I’m not trying to put words in Cass’s mouth, but I’m pretty sure these are the same units that he uses. He tears them apart and cleans them, checks tolerances, fixes any machining errors, and replaces the hardware. After all that, he backs that thing up, definitely worth a couple hundred bucks extra to go through @DoctorDiff
 
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I’m not trying to put words in Cass’s mouth, but I’m pretty sure these are the same units that he uses. He tears them apart and cleans them, checks tolerances, fixes any machining errors, and replaces the hardware. After all that, he backs that thing up, definitely worth a couple hundred bucks extra to go through @DoctorDiff
No doubt about it.
 
This time last year I bought a SG unit from Cass (Dr. Diff). I was told that it was the last one he had on the shelf and that he wouldn't be getting any more for at least six months. Supply chain issues etc.

Mopar 8 3/4" (8.75) Clutch Type Sure-Grip ("Powr-lok")

We ended up sending it back to him because the ring gear dropped right on. Despite being told that the bolts would hold it in place, my rear end guy didn't feel comfortable assembling the unit. Cass sent me a return shipping label and offered me a refund. I put the money towards one of his helical sure grip units.

Mopar 8 3/4" (8.75) Helical Gear Sure-Grip ("Sure-Trac")

I don't believe you're going to get that kind of customer service from an eBay seller.
 
I have carefully read the responses and decided to pass on one of these units. Thanks everyone, kind of confirmed my gut feeling. I appreciated the responses given!
 
This time last year I bought a SG unit from Cass (Dr. Diff). I was told that it was the last one he had on the shelf and that he wouldn't be getting any more for at least six months. Supply chain issues etc.

Mopar 8 3/4" (8.75) Clutch Type Sure-Grip ("Powr-lok")

We ended up sending it back to him because the ring gear dropped right on. Despite being told that the bolts would hold it in place, my rear end guy didn't feel comfortable assembling the unit. Cass sent me a return shipping label and offered me a refund. I put the money towards one of his helical sure grip units.

Mopar 8 3/4" (8.75) Helical Gear Sure-Grip ("Sure-Trac")

I don't believe you're going to get that kind of customer service from an eBay seller.
That helical gear unit is very nice. . Kim
 
I bought my differential on e-bay motors, it is a sure-lok diff. I bought the bearing kit for a 742 case from summit (complete kit) with Timken bearings. Put in 391 gears and it runs great all is working as expected. In my opinion they are ok. I can't say great cause I only drove it for the break in miles, but it did do great hole shots with no problems yet. I guess I'll find out with more miles. The seller on Ebay said they would take care of any problems as long as I used new bearings and races. They gave me a direct phone number.
 
Give it a shot and tell us what you think! I wouldn't want to be the guinea pig, that's for sure. Setting up a ring and pinion is a job I only like to do once.
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That gap between the cross shafts and ramps doesn't seem right. I read 0.010" somewhere max, this is over 0.030" easily and crooked.
 
20 years ago I sold Yukon 8.75" Power-locks, which I re-worked. The Chinese power-locks on eBay appear to be a copy of the old Yukon offering.

10 years ago, I had my own version made, which I assemble in-house. None of the components are made in China and they look completely different than those sold on eBay. See below:
Mopar 8 3/4" (8.75) Clutch Type Sure-Grip ("Powr-lok")
 
20 years ago I sold Yukon 8.75" Power-locks, which I re-worked. The Chinese power-locks on eBay appear to be a copy of the old Yukon offering.

10 years ago, I had my own version made, which I assemble in-house. None of the components are made in China and they look completely different than those sold on eBay. See below:
Mopar 8 3/4" (8.75) Clutch Type Sure-Grip ("Powr-lok")
Cass, are u still gonna be selling sure grips? Mim
 
Personally, I'd spend the extra money and buy the one from Dr. Diff. I have dealt with him in the past, and he is great. In his post on this thread, he indicated that no parts are from China, and that's worth more to me than the 200 dollar difference. It's one thing to ***** about China, but it's more important to stop supporting the fuckers!
And another thing, I have never seen "top parts us" posting or sharing anything of value on this site!

Cley
 
Personally, I'd spend the extra money and buy the one from Dr. Diff. I have dealt with him in the past, and he is great. In his post on this thread, he indicated that no parts are from China, and that's worth more to me than the 200 dollar difference. It's one thing to ***** about China, but it's more important to stop supporting the fuckers!
And another thing, I have never seen "top parts us" posting or sharing anything of value on this site!

Cley
Agree and when that piece of **** china part mucks up your tranny will be comming out for repairs also .
 
the response i got from dr. diff when i reached out to him a few months back..

My Power-Lock is better than the original. The gears are cr-mo and the units have less runout.

The Sure-Trac differential is stronger due to 12 helical gears (6 per side) compared to 4 total spider gears, however.

Thanks,

Cass
 
Personally I wouldn't buy one, but I know some of you will. I would strongly suggest you replace the bolts before you ever start using it and make sure to Loctite them in.

Tom
 
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