The guy selling green bearings? Say it ain't so.
He also sells tapered bearings, and even upgraded, heavy duty adjusters for those tapered bearings.
TheThe bearings are certainly not backwards. The corning load is carried by the opposite side bearing.
Yes, they are. When compared to typical wheel bearing assemblies anyway. You know, like the front wheel bearings. The bearings aren't retained by the race, and the end play is set with a nut and washer instead of by a separate adjuster.
TheShow me a stack of ruined 8 3/4 splines due to limited spline engagement, and I can probably find you a bigger stack of ruined 8 3/4 housings due to green bearing failure.
And I can show you some ruined housings caused by the bearing races fusing themselves to the housing ends after the outer gasket leaks. It happens.
TheTrue, foam seals don't keep water out. Taken from Dr. Diff's own web site:
View attachment 1715103693
TheI don't know if I want bearing advice from a guy that says his rears are unsealed, but sells the seals and doesn't seem to know where they go.....
?
One side gets the metal gasket, the other gets the foam gasket.
Both sides have to seal to keep water out of the housing.
TheAxle flange standout/side variance (due to end play) measured in thousandths (0.00x") of an inch, in a car with axle location production tolerance at an eighth of an inch (or more)? Sure thing.
Yeah well, try installing rear disks. The axle housing being shifted an 1/8" doesn't change anything for the stock tire widths, doesn't matter at all. The factory didn't consider people not being able to use a tape measure to figure out how big a tire would fit before they bought it. The factory "fixed" the factory race cars with a BFH. They didn't think people would balk at rolling a fender lip.
TheAgreed. What was the design flaw with stock, again?
Weaker carriers because of the cross pins. Pay attention.
TheBecause these bearings are not designed to accommodate side loads. Wiggle inside the housing? You mean, like you're (Dr. Diff) saying the bearing is supposed to wiggle in there? Uh, no....Stock bearings don't wiggle, and neither should green bearings. That's probably why there's not a single provision for "wiggle".
Ever heard of "end play". Yes, the stock bearings "wiggle". No, that wasn't the best term for Cass to use there. But yes, the green bearings will move, because like every bearing on the face of the planet there has to be some kind of end play. How the bearings design accounts for the end play changes depending on the design. If there was no end play, you'd overheat and ruin the bearings when they expand with heat. The green bearings with the snap ring address this by being able to move in the housing slightly. The snap ring is captured between the flange plate and the housing. There's play there.
TheUh, what? The axle is pre-loaded against the thrust block (proving: no side load capability), and the bearings fail? If only there was some way to prevent preloading....some way to keep end play in there....some method, an adjuster of sorts, that allows endplay so we don't preload stuff.....
Riiiight. If you install the green bearings
incorrectly, ie, they're bound up against a thrust block that they're not designed to use, you eliminate the play the bearing is designed with and they burn up. No different than not putting enough end play on the stock tapered bearings. Set the stock bearings too tight, they will also fail. Most folks remove the thrust block when they install green bearings.
TheYup, because the axle side loads are carried where? somewhere else. Apples: Meet oranges.
Remember the bit about the bearings "wiggling"? Yeah, there. It's a different design, by that very fact its and apples vs oranges comparison. They do the same job in different ways.
TheSnap ring? What's the snap ring do? I hope it's not carrying cornering loads.
So you admit you don't understand how these bearings work then? The new MO-400 bearings are pressed in until the snap ring hits the housing. It's then trapped between the housing and the flange/retainer plate on the end. There's
some play there. The retainer plate carries that load. Just like the stock retainer plates keep the race from sliding out of the housing.
TheMopar Housing Gasket+Seal Kit for 8 3/4" (8.75) or Dana 60
for reference above. Sounds like the new bearing is a dual-taper/angular-contact cartridge style.
Uh, read the information on the page. "COMPONENTS FIT OEM-STYLE MOPAR PASSENGER CAR REARENDS ONLY!"
That's the seal and gasket kit for tapered bearings. Remember, DoctorDiff sells BOTH styles of bearings.
TheAnd what, pray tell, is the correct way to install them that so many people (including the folks at Mopar Performance, who recommended you not install them for anything other than drag racing), are failing at?
Remember the bit about Mopar Performance still selling the early design sealed bearings? No? Again, pay attention, it's in the comments made by DoctorDiff. Mopar Performance makes that recommendation because they use the early style green bearings (the ones without the snap rings). So, the correct way to install them is to NOT USE THAT STYLE on the street. The MO-400 bearings are the ones you should use on the street, not the MP bearings that have the RP-400 design.
The hub assemblies don't use a green-style bearing (Edit, I'm considering this in reference to the old-style green bearings. No comment on the "new n' improved" ones). They're angular contact ball bearings. Using angular-contact balls instead of tapered rollers, they absorb thrust just like a Mopar 8 3/4; there's no diff in the middle and the end play is controlled via fixed spacer.
So, you're admitting the new design green bearing work then? Since you're dropping the argument about the new design and only considering the older design which we know to be flawed?
Of course, there's more maintenance involved, but factory 8 3/4 bearings will last as long too. Green bearings (Gen 1? Gen 2? beats me) maybe not so much.
The second design, gen2, whatever you want to call the MO-400 bearings that DoctorDiff sells works just fine. Despite the fact that I myself prefer the tapered bearings, I have a set of the MO-400 bearings installed in my Challenger. The one that I've put 60k miles on, daily driving, while running 275/40/17's all the way around and flogging the crap out of on mountain roads, corners, and even probably hundreds of miles on gravel roads. I've had no issues with them. I've worn out brakes, had other aftermarket suspension pieces fail etc, but those bearings are fine.
Are the green bearings better? I don't think so, actually. Are they a problem? No, they work fine. If they'll do 60k miles they way that I put those 60k miles on my Challenger, 99% of the people that use them in their classic mopars will
never have to even think about them, because they'll never put that many miles on them. Because the number of folks that put 10k miles or more a year on their classic mopars is getting smaller every year. Heck I don't always hit that mark every year anymore. Most people on here log less than a couple thousand miles, and at that pace if they install a set of green bearings it will be the owner AFTER the
next owner that has to think about changing the axle bearings. Cause it'll take two generations to log enough many miles at that pace. And, driving it to the local show or the dairy queen isn't going to bring out the flaws in the sealed bearings.
