Dana 27a Front Axle Gear Set Recommendations

Repair needed on 1967 CJ5 w/Dana 27A front axle--vertical tag on housing cover = 941052 / 4.88 gears / 39 teeth on the ring gear and 8 on the pinion.

Sheared about 1/3 of the teeth off of the right side differential side gear. In other words, the differential side gear on the short axle-shaft (passenger side of CJ5).

Have not gone any further than to remove housing cover and visually see the damage. Seems to be one gear only.

Planning on purchasing a gear set as pictured. Any recommendation? Who offers quality?

 

While I'm sure there are quality parts still available for the Dana 27, many will wonder how the spiders were sheared.
What size engine and tires are your running. We just wouldn't want to see the same failure again.
I used to run a Dana 27, 4:88s and 33's but have a stock V6. The weak link is usually the knuckle attach.

 

I am willing to try a rebuild of the Dana 27 and live with it's limitations. What I believe took it out was deep mud holes, with stop and GO--bad timing of heavy accelerator, mixed with reverse in an attempt to back out. I understand too much was "asked" of the Dana 27.

Though I don't look forward to the repair, I'm prepared to go easy on it. The incident was the first, and hopefully last, in the mild wheeling with this set-up on the Jeep in question:

Year/Model: 1967 CJ5
Drivetrain: V6, T98 4-spd, Dana 18 single stk
Axles: 27A (front) and 44 (powr-lock rear) with 4.88's
Wheels/Tires: 33 x 10.50 - 15 BFG Mud-Terrain

 

I blew the spider gears out of the D27 in my 67 Cj5 just backing it up in the woods to turn around. I doubt it had 7k miles on it at that point-nearly new. I think I would be looking for NOS or even good used Dana. I suspect you will find most stuff offered new is going to be Omix or maybe Crown. I personally don't think either is worth the effort to install. Pretty sure D25's and D27's use the same spider/side gear set.

 

I've blown out my 27 as well.
I found a great, albeit more costly upgrade to be a powr lok traction diff. The LS not only is overall stronger, but it helps smooth out the shock load, which can save the R&P as well.

If you are going to push the front end a bit, I would suggest a long range plan that includes this upgrade.

 

Yes, the Powr loc's 4 spiders versus 2 on the open is a lot stronger. But as for spider gears, the D25 and D27 share the same axle shafts and IMO, those are right on par with the 2 spider gear arrangement as to strength. And putting a non-selectable traction device in front axles also makes running on packed snow or ice in 4x4 mode very interesting. Maybe VERY INTERESTING. The real cure here is a narrow track D30 but short of that I would just be looking for some Dana replacement parts. Put a WTB post in the classified and hopefully someone close by will have a set.

 

As long as your ring and pinion are not hurt, replace the spiders or drive gears with NOS Dana parts or good used take-outs. An open diff allows one tire to spin up where the other side isn’t turning, and if the spinning side catches traction, your drive gears can pay the price as you found out. It an easy job to just pull the center section and replace the spiders/drive gears only. The backlash and setup should remain unchanged as long as you keep everything on order as is came apart.
This may be be a good time to consider a limited slip, but that does require a fresh setup of the diff.
-Donny

 

Inspect your case closely. I've seen where the case is cracked where the roll pin goes in.

 

There should be a lot of used axle gears around if you search a bit, and you will have much better quality parts than the new ones.

 

Everyone who has put a Lock-rite in has removed the gears in your picture. As Duffer said put a WTB and in here and someone will make you a good deal on original parts.

 

My offroad wheeling is generally more technical and slow, with occasional trips to the snow.

I installed the PL in the mid 90's after the stock carrier blew. It has been, OMHO, the best upgrade (for the 27) for the money. It smoothed out the shock loads (wheel bounce under load) and provided added traction up front. I've had no axle or U joint issues.

I've wheeled it in the snow and the PL is very well mannered.

Only added step to installation is resetting the backlash.

 

This. I put a PL in not so much for traction as a stronger carrier. Yes, you are still dependent on tiny axle shafts, but I would rather change a shaft than a diff.

And this. I have seen this a lot. and a good argument for a PL.

 

Maybe. When I blew the right side shaft in my 3B, it literally exploded and took the inner axle seal and it's seat completely out. That whole housing ended up scrap. That shaft failure was classic as to what happens when you do stress those 10 spline shafts. This was a Spicer shaft.

 

Thanks Everyone-- I'm getting an education!

A link for reference: https://www.theengineerspost.com/differential/

Inside the differential case, there are two side gears and two pinion gears. The pinion gears are technically the spider gears, but many people simply refer to all four of the gears as spider gears.

 

Placed a Wanted to Buy in the Early CJ5 classifieds on 1/24/23 for a good used gear set.

Edit: Thanks all. The purchase of the OEM front Dana gears is in progress -- on 1/24/23.

 

Got a good set of take-off gears (OEM) to replace the damage ---Thanks jpflat2a.

Now I have a question re: the differential --

I can't place even one side of the two .030 concave small thrust washers without binding/stopping rotation.
Is it okay to leave these concave pinion gear washers out? or am I missing something about proper installation?

When I took it apart there were no side concave washers in there, been that way since I owned the Jeep. I don't know if there ever were.

I did install the two large thin washers behind the side gears

 

What is the thickness of the flat side gear washers? Take one of them out and then see if the concave washers will rotate in. Here is what I'm thinking, the side gear flat washers are too thick pushing the side gears too close together for the concave washers to fit. Sounds like Duffers idea that the housing might be twisted or damaged causing the problem your having. I have a similar stub 10 spline I've kept in my toolbox from around 2000. But I didn't have your issue

 

That question caused me to inspect the flat washers and still it was almost impossible to tell I had double washers on both sides. All is better now. Tomorrow I'll have to check/adjust the side gear clearance per the FSM.