HOW TO: Installing a Lock-Right Locker in a Dana 80 Axle


Wooohoo!!! The first, HOW TO article to kick off the HOW TO Series.  The reason I am launching a HOW TO series is because I am finding more often than not install posts that are either misleading or full of misinformation or sadly both. I wanted to highlight one of my recent trials of being told multiple times that a certain install was going to go one way only to find out for myself, that the install was going to be much more involved than the Keyboard Warriors and even the product’s own install instructions proclaimed.

 

So here is my problem. On doing a routine differential reseal on my rear axle in my truck, I came to see a horrifying sight…. My rear differential was an OPEN differential. Meaning, I had no limited slip, I had no traction device and instead…. I was blessed with a peg leg (one wheel turning) monster.

What was I to do? I really did not need to know this, and as I am taking the truck on more and more aggressive trails having an open differential in a 7500 LB rig really limits what one can do. Now do not hear that “you cant” 4x4 and travel a lot of this green earth with an open differential, but when certain situations arise with a vehicle that has an open differential, you are forced as a driver to drive faster than you would like to and really balance that fine line between abuse and skill. Personally moving slower in harsher terrain probably prevents carnage on a level of 10 to one…..watch Youtube….most of the 4x4 accidents out there happened because speed and skinny pedal are not always the answer to every solution.

So back to the install. I am not ready to go to a full blown Locker at this time, money does not dictate this as an option and with funds needing to go to other aspects of the truck, I need a cheaper solution than spending 1500-2200 to install a new Locker such as an ARB, Detriot, etc. Plus, I am looking at regearing my truck from 3.54 to 4.10 and with that comes almost an additional $750 dollars+ for ring and pinion gears and unknown labor for setting up the front axle to match the rear axle. Or…..I could grab a Lock Right Locker with a street price around 450 bucks and solve my problem currently and keep my build moving on. The idea was also the fact that an install like a Lock Right Locker is fairly straight forward, meaning anyone should be able to perform the task as long as you have a good mechanical understanding of properly torqueing bolts and keeping your assembly absolutely CLEAN and free of foreign debris.

1) So, if this went according to how the interwebs and the instructions tell you… All I would have needed to do is drain the oil from the rear diff, pull the pinion shaft from the differential, remove the 4 spider gears and we are well on our way… The problem is, as you can see…. Those rumors may work for Dana 30’s, 44’s and the like, but the ring gear of the Dana 80 is too freaking big!! There is no way to pull that pinion shaft with the assembly in the housing. Also, this pinion shaft is not held in by a bolt, the Dana 80 open carriers have a roll pin. This means even if the shaft would come out with the ring gear installed,  there is no way to hammer the roll pin out and then hammer the roll pin back in to secure the pinion shaft. This meant the whole differential assembly had to be removed for the install.

Now honestly… this development in how I needed to proceed with the install is not a total game changer. But you will need to have a few more tools than you previously needed. The first is you need an ACCURATE Torque Wrench that will go to atleast 200 Ft Lbs.  As the ring gear bolts on the differential need to be torqued to #180 Ft Lbs. I also highly recommend a fastener thread locker such as Blue Lock-Tite. Now, industry wide as a mechanic, you normally never re-use ring gear bolts. It is always recommended to replace the ring gear bolts. But again…here I am on a  Saturday and need to drive to work Monday. Blue Lock-Tite and proper torque will be fine. YOU CAN use the bolts and be fine. Just don’t come after me if you have a problem.

Open carrier….and NO way to get that pinion shaft on with the Ring Gear on.

Open carrier….and NO way to get that pinion shaft on with the Ring Gear on.

2) First physical step is to now pull the axle shafts, this is an easy process. I recommend having 2 drain pans under each floating hub. Gear oil will be draining out as this is the oil that has splashed into the tubes and keeps the axle bearings in the hubs lubricated. Slide the axles far enough out of the hubs that they tilt in the axle tubes.

Here the axle is pulled out of the carrier and there is a drain pan to catch the gear oil.

Here the axle is pulled out of the carrier and there is a drain pan to catch the gear oil.

3) Now with the axles out of the differential carrier, it is time to pull the carrier. This is my recommendation. Make sure you have a clean flat surface to place the carrier on once it has been removed from the axle housing. The reason being is this assembly is awkward and easily a 70 pound chunk of iron. You absolutely do not want to drop this… any damage to the ring gear, or the ABS ring (speed sensor) or either carrier bearing could lead to a much longer install as you source and install broken bits.

Pro TIP- MARK each Bearing Cap, they MUST go back into their original positions in the axle Assembly. You cannot place the left, cap on the right cap, YOU CANNOT flip the caps 180 degrees. Mark them some how so you know exactly how they came out of the axle housing.

2ND TIP-Make sure you know which bearing race goes to which carrier bearing, YOU CANNOT SWAP THEM SIDE TO SIDE. I used a little dab of model paint, red for right side, blue for left.



4) Again, make sure you have a clean work surface. ABSOLUTELY CLEAN. You do not want grit in any bearing, ring tooth, etc. This must be a clean surface. Wash your hands, treat this as if you are making a sandwich YOU ARE GOING TO EAT. Now you need to have a roll pin punch and you need a BFH (Big Friggin Hammer). Now someone in the engineering department at DANA has a sick, sick sense of humor and designed the roll pin of the Dana 80 pinion shafts to be .225 in size. Oh, but Adam…that’s not a common size.. I KNOW. A 1/4 punch is too big, a 3/16 punch is to small. I also was cursed with the fact that when my carrier was built someone had just gotten a letter from his ex wife asking for more money, because my roll pin hole was not fully finished when machined. This would lead to 3 prayer candles being lit and several sessions of curse word charades.

PRO TIP: Do yourself a favor and order a NEW roll pin before doing this install. They cost a whopping $2.07 on the internet. I could have saved myself HOURS of headaches if I had a new roll pin. But I was stuck in the shop on a Saturday with no way of getting parts until Monday. I had to make what I had at my disposal work.

If you have the ability….utilize a ¼ inch punch and a press, and you can gently press the roll pin just far enough past the Pinion shaft that you can pull the shaft and move on with the install. My problem existed in that I used the BFH and the oversized .250 punch and hammered the roll pin out far enough to pull the pinion shaft. What happened internally, is my unfinished carrier and too large of a punch caused the roll pin to mushroom/wedge itself into the backside of the carrier. More on that later.

Ring Gear is removed to facilitate pulling the pinion shaft.

Ring Gear is removed to facilitate pulling the pinion shaft.

5) Use a brass punch and gently tap on the Pinion shaft, my pinion shaft happened to still be quite tight and so I had to use the hammer all the way out, but again, little taps, very little pressure. Now with the shaft removed the spider gears or commonly referred to as the side gears, can be removed through the larger windowed hole in the carrier. Remember you need to save the thrust washers off the back side of the side gears. these thrust washers will be reused on the new “coupler” gears of the Lock-Right Locker.

Now with the Carrier empty it is time to clean everything again. I like brake clean and fresh rags. Completely clean the carrier of grit and oil. The reason being is your carrier has probably been spinning around in that diff for what…. 10 years? 20 years? Or like mine…340K miles. No matter how often the rear end may have been serviced there is grit, grime and goo hidden in the carrier. Now with a Locker going into it, lets make sure none of that grit finds its way between the teeth of the locker or binding up in the springs of the locker.

Empty carrier cleaned a prepped for loading Lock-Right assembly.

Empty carrier cleaned a prepped for loading Lock-Right assembly.

6) Assembly of the Locker- I recommend setting the locker up on a clean table, get an Idea of how the system works, inspect the teeth, drivers and side gears. Make sure all the springs are there, make sure your 4-detent pins, (my kit came with 4 spares which is nice if I need to service this unit in the future. Your instructions will walk you through different assembly procedures, the Lock Right unit comes with 8 springs, you need to put one small spring, into one large spring and in doing so will then have 4 “dual spring” assemblies that are used to force the Lock Right Driver gears into the Side Coupler gears.

PRO TIP: Use axle grease to keep the 2 springs together and BE LIBERAL with the grease. Working as a mechanic I was once taught by a very wise mentor that when trying to install springs into ANY assembly, placing axle/bearing grease on the springs will make sure that once the springs has left orbit the spring will STICK and not roll away.

Here we see how the Lock-Right assembly will look loaded into the carrier.

Here we see how the Lock-Right assembly will look loaded into the carrier.

7. Loading the Carrier- Now with everything cleaned, and with a general idea of how your locker works, you will load the carrier, I recommend placing a liberal amount of axle grease on all of the locking teeth of the assembly. This ensures that the unit will have adequate lubrication until everything splashes around. (Yes the assembly is buried in a bath of oil once filled, the instructions say to do it, and it actually makes assembly easier as parts of the locker will “stick” together while you finish the install and fight gravity.) You will load one side of the locker with the side coupler gear AND thrust washer, along with the appropriate internal spacer, then next is the matching center driver. Now you need to load the opposite coupler side gear, thrust washer, spacer, driver and push the NEW forged pinion shaft through the center of the diff. CONGRATS you are on the down hill slide!

As seen, liberal amounts of axle grease helps keep parts of the assembly together as you prepare other pieces

As seen, liberal amounts of axle grease helps keep parts of the assembly together as you prepare other pieces

8. Installing the springs and pin. This part is pretty simple as the windows in the drivers of the Locker are machined really well, so the pins go in without a problem, a tiny flathead makes pushing the detent pins over an easy task. Now it is time to install the springs. This part is easy as long as you have a vice or a good friend to hold the carrier. I fought to install one set of springs and did so in about 15 minute with multiple failures to seat the spring. I finally pushed past my pride, asked a friend to hold the carrier and BOOM, I had the last 3 spring assemblies in the carrier in about 3 minutes

9. At this point the instructions will tell you to take measurement between the driver gears to assure you the carrier is not too worn or that you do not need an EXTRA thrust washer, which SPOILER ALERT…is not provided in the kit… Pray your measurement comes out in spec. Otherwise….its a bad day.

10. Remember that DAMN ROLL PIN? In a perfect world, this is where you flip the carrier over, and punch the roll pin back into your new forged pinion shaft and you are ready to load the whole assembly back into the axle housing. For me…. This turned into a 4 hour detour. So let me suggest what I would have done. First…way back at the beginning, inspect the roll pin hole. Mine had a burr in it, I knew it and saw it and was lazy…if I would have taken 2 seconds to run a .250 drill bit through to the seated roll pin my whole install would have gone smother. Personally, this is how I would do it again. The roll pin sits roughly 2.07 inches long, so if I relieved the back side of the pin hole all this would have done is made it easier to drive the pin out, I could have then driven the pin back in the front side and completely missed all the excitement of breaking 6 punches and having to build my own tool to use in a 100 ton press.

Roll Pin hole that had to be de-burred and machined to relieve now Mushroomed Roll Pin.

Roll Pin hole that had to be de-burred and machined to relieve now Mushroomed Roll Pin.

100 ton press, patience and 6 bent, broken or destroyed punches later…

100 ton press, patience and 6 bent, broken or destroyed punches later…


11. Clean your ring gear, inspect and clean every ring gear bolt. Now I would install all of them with blue Lock-Tite (That is exactly what I did). These bolts need to be torqued to 180lbs at least. There are multiple work shop manuals saying multiple things, I read 180-240, with most falling in between 180-190, I took mine to 185Lbs.

12. Now install the differential assembly back into the axle assembly, make sure you have the correct bearing race on the correct carrier bearing. Also know that the Dana 80 has equal width axle bearing spacers on BOTH SIDES of the carrier. Make sure those spacers are back where they need to be. The Dana 80 Carrier Bearing Caps have 2 bolts a piece, these bolts need to be 80 FT LBS. I like to install mine at 20FT LBS to begin with, then I go to 50 ft lbs, and then finally to 80 ft lbs. I again used Blue Lock-Tite on the Bearing Cap bolts.

LOCKED AND LOADED

LOCKED AND LOADED

13. Install your Axle Shafts and Torque to whatever specs you like, personally 60 ft lbs has always worked for me.

14. At this time you can check to make sure the unit is working. Basically. Make sure that when you turn either wheel, the opposite wheel is moving in the same direction. Lock Right has a procedure in their instruction manual for checking if the locker works. I couldn’t get mine to react in the way they wanted and with knowing how difficult that roll pin had been in assembly I was driving home regardless…with a working locker or an expensive spool. (My Locker works as it should)

15. Filling the diff for fluid, a 4x4 Dana 80 specs out with needing 10.1 pints from the manual. Mine took 10 flat. Lock Right will say you can use 80w/140 Gear Oil to quite the Locker. (Basically thicker fluid acts like a greater sound deadening advocate. My truck is a 2nd Gen Cummins, I couldn’t hear that differential if I wanted.) I used regular ole 70w-90.

All Buttoned up with a Dynatrac Diff Cover.

All Buttoned up with a Dynatrac Diff Cover.

My Experience so far: I now have 5,000 miles on my Lock Right and 3 off road trips. To put it lightly, this Locker was worth every penny. I lucked out and got my unit for a song through someone I met at SEMA 2018. But even at the going rate of around $450.00 dollars, you are looking at something AT LEAST 700 dollars cheaper than the next available unit installed. Honestly, aside from my nightmare, a shop should realistically be able to charge 3 hours at 105 dollars an hour, 80 for fluid and you would still be at around the 860 dollar mark out the door without touching a wrench. For me, I would still do this myself, I happened to draw the short end of the stick on this one. O well, But for the cost of the unit, a Lube Locker Gasket and fluid, I couldn’t have come close to finding anything better than what I have. I have had this unit in the snow, mud, sand, gravel, etc. The unit works consistently and has rarely spooked me. If I get on the gas mid turn the unit will lock up and I will get a chirp from the rear tires, but I have not had a problem of feeling unsafe or regretting my install. In fact every time I am off road I fall more in love with it. The Lock Right is warrantied up to 35 inch tires so for most people this unit will be a great choice and final solution to their traction woes. I am currently on 285’s and one day will move up to 37’s. But when I move up to the big meats, I will most likely re-gear and then have to decide whether I want a Detroit or ARB. But for now, I love my Lock Right, everything has been straightforward and I cannot be more pleased! Places where I would immediately put my transfer case in 4wd I can muster through with 2wd. It is amazing how much your vehicle changes when you rear tires turn with 100 percent power!

Thank you for reading!

-Overland Therapy