axle locker question.

okay thanks guys.
im gonna talk to my buddy about his axles.
see if he wants to get rid of them.

 

Had a Trac Lok in the rear, blew it up 3 times, rebuilt it twice and I now have a Detroit. I found a Power Lok for the front and love it. I am running 4:88'S and Warn OD, seems to be about the best combo around.

 

Yes that stands as true and correct.
Front Powr-Loks were never from the factory for any V-6 CJ's.
Not for 4.88 ratio model 27 and not for 3.73 ratio model 27.

However the rear Powr-Lok and the subsequent rear Trac-Lok were available as factory options for these same V-6 powered CJ's.
Powr-Lok and Trac-Lok carriers are not interchangable as an assembly.
Remember Powr-Lok fits 19 splined rear axles. ( tapered )
Trac-Lok fits the 30 splined rear axles. ( flanged )

I feel that the best Dana Spicer ever built was the 4.89 (44 ring - 9 pinion) Powr-Lok model 44 "offset" HEAVY DUTY rear axle.
There are a multitude of factors to consider as to why it is so desireable.
These were only available for about two and a half years.
Modified to a full floater they have even more potential than the infamous Trac-Lok flanged axles.

 

Power Locks were also available in the flanged offset 30 spline axles.

 

Wait a sec.....
I sure don't claim to be any kind of Thornton Powr-Lok expert but .....
If one has a Powr-Lok carrier installed into a 30 spline flanged model 44.
Then the carrier assembly is modified using a combination of the Trac-Lok pinion mate gear set installed into the Power-Lok carrier housing. Right ?
Now does that make any sense to you Nickmil ?

If you don't mind I am curious what broke on your Trac-Lok ???

Good Luck ******* ! Were pulling for ya.......

 

I have a power lock for the flanged 44 rear axle. Bought it from Nick about 2 years ago. Looks just like any other power lock to me.

 

I belive it was the springs or the little clips both times. Been a while. I still have it in the garage, guess I could go look.

 

First, let us clear up something here. A "carrier" is the part that houses the ring and pinion, differential case, etc. In the case of a solid axle dana 44 the tubes are pressed into the "carrier". As an example, the carrier on a Ford 9" rear assembly is the part that bolts to the axle housing but has a whole series of nuts or bolts that can be removed to remove the "carrier assembly", also commonly referred to a "chunk, hogshead, third member" etc. The differential "case" is the part that houses the differential pinion gears, differential side gears, and that the ring gear or crown wheel bolts to.


Second, I'm not real clear on what you are saying here

"If one has a Powr-Lok carrier installed into a 30 spline flanged model 44.
Then the carrier assembly is modified using a combination of the Trac-Lok pinion mate gear set installed into the Power-Lok carrier housing. Right ?"

But no parts of the Trac loc are interchangeable with the Powerlock except the carrier bearings, preload shims, and ring gear bolts, PERIOD. The case, side gears, pinion gears, differential gear thrust washers, clutches, etc. etc. are completely different.

The Powerlock uses 2 pinion shafts, 4 pinion gears, a completely different clutch pack, different side gears, and a bolt together case.

The Trac Loc uses a one piece case, 2 pinion gears, and different side gears, pinion shaft, clutch pack, etc.

If you are talking about the drive pinion and ring gear, commonly referred to as a ring an pinion set, then they will mate to either a Powerlock or Trac Loc as long as the "series" of the case is the same. To give you an example, the 4series case on a Dana 44 fits 5.38-1 ring and pinion ratio to 3.92-1 ring and pinion ratio. The 3 series case fits 3.73-1 ring and pinion ratio to 2.72-1 ring and pinion ratio.
As long as the "series" of case is the same the ring and pinion set will work with either.
The difference between the two series is the distance between the centerline of the "carrier" and where the ring gear bolts to the "case". Because as the ring and pinion ratio gets lower (numerically higher) the drive pinion tooth count decreases the drive pinion gear diameter gets smaller so the flange on the case where the ring gear bolts must be closer to the center line of the "carrier". As the ring and pinion ratio increases (numerically lower) the drive pinion tooth count and diameter increases, the flange the ring gear bolts to must move farther away from the "carrier" centerline to accommodate the the spacing difference.

As I said, the offset flanged 44 used in CJ's was available with the Powerlock. Seen many of them personally. They were more common in the '72-'75 CJ's 44 flanged centered rears, but were available in the earlier units. They were also available in GM's, Fords, Dodges, IH vehicles, Chevrolet Corvettes, some Volvo cars, and probably many other applications I can't think fo right now.

I've been professionally building transmissions, transfer cases, custom and stock Dana/Spicer diffs, etc. for about the last 15 years and have honor of knowing some of the big players in the Jeep and offroad industry. I've been around Jeeps, anything from bone stock to Jeep sheet metal on a tube frame, for most of my 40 years, and this is the info I've come up with not from a book somewhere, but from personal experience from working on Jeeps most of my life and from the others in the industry which have shown me the differences.

 

{throws hat into the ring}

If I recall, the 30 spline powerlock units weren't available for 71 and prior, flanged 44s, from Jeep.
We, being an IH dealer as well, bought from IH the 30 spline powerlock units used in rear 44 Scout 800 A-B models.
Those vehicles had 30 spline, flanged axles.

This is what I recall, because Jeep didn't use a powerlock with their flanged 44 axles, only tracklocks.

That's not to say one couldn't be ordered seperately and installed. I'm just saying you couldn't get it factory installed from Jeep.
If I'm wrong, well then, I'm dead wrong and carry on.

 

It's very possible they were dealer installed units or special order units Jim. By the time I saw them they were many years old but I know of several that came from the dealer with them. You shed some new light on this.

 

Yes Nick,

Apparently for me playing or being a little dumb works out very well on occasion.
I would never claim to be an expert; because as you know there is always something more to learn on Jeeps.

I understand and fully agree with your correctly termed technical explanation.
It feels really good to see someone else explain it straight up.
Your case series explanation has excellent detail.
I now apologize for injecting the term "carrier" in place of "differential case"

I was just looking over my NOS Trac-Lok side gear set this morning and the Spicer 44 Powr-Lok case I bought off you
You are certainly correct. There is no way that those Trac-Lok side gears will fit into the Powr-Lok differential case.

I also must agree with Jim.
I just can't believe that factory Jeeps ever had 30 spline Powr-Loks before 1972.
Factory offset model 44 is just not in any of the pre 1972 Jeep books.
Nor are the side gears that would be required to make the 30 spline axle shaft assembly fit.
I know this for fact as I have virtually every book before 1972.
Jim is likely correct.
Myself, I could imagine some Jeep Powr-Loks were potentially modified with IH Scout side gears ? AFIK

Thanks Guys.......