TECH: AXLES

ALL BALLS 8 BALL AXLE UPGRADE Tougher axles for less money  By the staff of Dirt Wheels

Axles on modern UTVs are expected to perform and survive under incredible conditions. Without constant-velocity joints in the axle, modern UTV long-travel suspension wouldn’t be possible. As the suspension cycles through its travel, the axles must flex, transfer a lot of power faithfully and make automatic adjustments in the axle length. A CV joint has a series of large ball bearings. An inner fitting holds the balls in place with the help of a cage. The balls extend through the cage, and they engage with half-moon slots machined into the outer shell of the joint. The balls transfer the power while letting the joint flex freely and plunge in and out.

It is rare that the steel shafts of the axle will fail, but quite common that there will be wear in the CV joints that can display some unwanted play or even fail. Fortunately, axles are usually quite durable, and if they do fail, they are easy to change with basic tools. One guaranteed way to destroy an axle is to tear a CV boot. A CV joint requires a large quantity of dense grease to function properly. If the boot fails, it will sling out the grease and allow grit in that will promptly make the joint fail.

A typical CV joint has six balls in each joint, but All Balls Racing 8 Ball Extreme Duty axles (not surprisingly from the name) have eight balls in the CVs. They are claimed to be stronger than stock CV axles. Like a lot of All Balls products, they are priced well, too. A stock Polaris axle for the RZR XP 1000 we were working with runs for about $250, but the retail price for the 8 Ball axle is $174.99. All Balls sells a normal 6-ball axle that is priced even lower. This is how to swap out front and rear axles.

1. If you are forced to replace or upgrade an axle, the good news is that you will not require a lot of tools. The only uncommon tool that you will need is a 32mm socket and a torque wrench that can handle the torque for the axle nut. Polaris calls for 180 pound-feet, but a lot of owners report using less than that

2. The first thing to do is to jack up the machine and get it safely on jack stands. Remove the wheel, axle cotter pin and loosen the axle nut. We used a 1/2-inch breaker bar and had a helper to hold the brake to avoid a load on the transmission.

3. A thick, cupped washer is under the axle nut. On some machines there are two washers. The washers have been known to crack. The washer should be installed with the convex side out towards the nut. Make sure to inspect the washer for damage or cracks.

4. Next, you will need to loosen and remove the bolt from the upper and lower radius rods. That job will take two wrenches or a wrench and a socket. As soon as the bolt starts to come loose, it will spin without the second tool to hold it.

5. With the radius rods released, the rear trailing arm will pull to the side and release the outboard end of the axle. Push the axle all the way in. The inner CV will plunge and push all the way in. When you pull out quickly on the axle, the CV will act like a slide hammer. A good pull should pop the axle out.

6. This is the new 8 Ball axle from All Balls Racing. It comes packaged complete and ready to go, including a new nut and a cotter pin. The 8 Ball CV joints have eight slots and eight balls to share the load that the CVs need to deal with.

7. Before you put the axle back in, put some grease or anti-seize on the splines where they insert in the transmission. The insert in the transmission and the axle are both steel. You don’t want the two parts to rust together. The lubrication will help the axle slide in.

8. Make sure that the splines are lined up correctly, and pull the axle all the way back in the joint without pulling it away from the transmission. Slam the axle forward into the cup to pop the axle in. It may take a few hits. The grease in the CV slows the effort you put in.

9. This is the inside of the CV joint. The inner part attached to the axle slides back and forth in here. Pull the axle back until it stops, then shove the axle forward quickly. It will plunge into the cup and give the inner axle stub a helpful bump.

10. Pull the trailing arm to the side to allow the outer axle stub to fit through the wheel opening. The stub needs to insert through the large bearing in the trailing arm. It should slide in easily.

11. After the axle is in, make sure the washer is in facing the right direction. Start the axle nut on the threads. That should get the trailing arm in position to allow the radius rods to slip back into position. Start with the nuts on the bolts that position both rods.

12. Tighten the bolts that attach the radius rods to the trailing arm. The radius rods are what control the travel arc of the trailing arm. Make sure the bolts are tight. Face the threads of the bolts in the direction that will get the least amount of dirt thrown on them.

13. After you tighten up the axle nut, use a torque wrench to make sure it is tightened to specifications. It takes a large torque wrench to reach the required torque. After the nut it torqued, inspect the washer to make sure that it is not cracked or deformed.

14. After the rear axle is completed (complete with a new cotter pin), move to the front axles. Pull out the cotter pin, then loosen the axle nut. Our cordless impact was able to handle the task, so it could not have been torqued to 180 pound-feet.

15. On the front spindles, the ball joints are the connection at the top and the bottom. Loosen and remove the bolts that trap the ball joints. The end of the ball joint has a half-round groove around it. The bolts don’t tighten the ball joints, but they do trap them in place.

16. In the front you will need to remove the caliper. Use a zip-tie to hold the caliper up so it doesn’t stress the brake line.We removed the lower shock bolt to give us more room for the A-arms to drop. That gave us more room to get the axle out of the front spindle.

17. With everything loose and the upper ball joint out, there should enough room to work the axle stub loose from the spindle. It is very easy to give your fingers a serious pinch that will draw blood if you are not careful. Don’t ask how we know.

18. We found that it helped to remove the brake disc as well. That inner sleeve that the disc rides on is long enough to make a difference while working the outboard end of the axle out.

19. We finally worked the axle out of the front spindle. After that was free, we plunged and pulled the axle just as we did the rear axle. That pops it free of the front differential. A spring clip on the inner axle stub is what secures the axle.

20. This is a side-by-side comparison of the stock front axle and the All Balls 8 Ball axle. They don’t look identical, and the axle bar itself is beefier, but all of the critical dimensions and machining are fully compatible.

21. We put anti-seize on the inboard splines, lined up the splines and pushed the axle in. We did not use any tool to force any of the axles. We did have to fuss with them a bit, but we were able to pop them in without resorting to force.

22. Once the axle is in place, work the front spindle back over the new axle stub. After it is in place, insert the ball joints, slide the bolts through and put the nuts on them.

23. Install the lower shock bolt and tighten it. You may need a hand holding the A-arms up to get the hole in the lower shock eye to line up with the mounting holes in the bracket on top of the A-arm.

24. We slid the disc back on, installed the washer and new nut. We tightened the nut, then torqued it. We figured it was good practice to clean the disc rotor with clean paper towels and brake cleaner. We didn’t want to risk the rotors getting some lubricant on them while they were off.

25. We torqued the axle nut, inspected the cupped washer for damage, then installed the new cotter pin to keep everything safe. We then cut the zip-tie holding the brake caliper. We bolted the caliper on and tightened it. We did the axles on the other side the same way, and we were good to go ride!