Ok when it comes to CV grease, I'll let you guys in on a secret. I've been involved in off road desert racing most of my life. I've won Score races & BITD Championships. I've been in everything from Class 1 Unlimited Buggy's, to 5/1600 Baja Bugs.
When it comes to CV grease we use Bel Ray. (Bel-Ray 67700 Molylube Anti-Seize Compound, Grade NLGI 2). It comes in 14oz cocking tubes. The cocking tubes are Awesome! Super easy to pump grease in without using your hands or sticks. I would guess one tube should do two compete UTV axles (4 CV's as UTV CV's are pretty small) This stuff is not cheap! It's around $45 per tube. But it's the best! It's the norm in desert racing and I would bet the Polaris JaggedX and other top teams are using Bel Ray. Bel Ray is rated up to 750 degrees Fahrenheit. We have had 1000's of miles on 930 race CV's and they show very little wear.
On the Class 1 car we have lost CV boots and continued to race with only pumping in more grease at pit stops. Bel Ray is a Moly Paste with Anti Seize and this is what makes it so good. This is what will stain your hands too! Bel Ray is thick and does not liquefy even at extreme high temps. This is what keeps it in the CV and not in the boot.
We have learned many boots rip as the grease melts and is flung into the boot. The centrifugal force causes the boot the rotate and deform out of shape with the grease in the boot causing them to rip.
I worked with Huskey Lubricants to develop a better CV grease back in 2003. What they came up with was a combo of their Moly & anti-seize grease. Basically what Bel Ray was making. A limited production was made and tested. It worked great, but the higher ups pulled the plug as it was going to be a specialty grease and they felt is was not going to be cost effective to mass produce.
If Bel Ray is to costly for you look at Caterpillar Grease ( Cat Gold ). This is much cheaper and works very well on limited HP cars, which the UTV would be in that category. Many limited class teams us it with great success. I have used Cat Gold in the Prerunners. But if you want the best look at Bel Ray.
Now the secret is out. Keep using your PepBoys cheap universal grease and keep having issues, or look to the best.