Green Bearings

[dfrazz]

I bought a rear disc conversion kit and it says it requires green bearings. Does anyone know why and what are is the difference between green and regular bearings?

 

[moparleo]

The green bearings are sealed, non adjustable, low sideload strength, cheap ( compared to the original tapered bearings)

 

[ramenth]

I'm taking it you're converting an 8.75. Green bearings are a roller bearing in a cage, inner and outer races, something like you'd see in a front wheel drive. The 8.75 is equipped with tapered bearings, conical shaped.

There's some argument on rather or not to use green bearings on the street when it comes to the 8.75. Some say it can't handle the side loads of cornering, others say run it and you'll have no issues. I'm not gonna get into it. But the answer lies in the above paragraph.

 

[dfrazz]

Thank you for the clarification as I've never heard of green bearings. The brake kit (from PST) says it requires green bearings. Does anyone know why and issues if I stick with the tapered?

 

[challenger6pak]

It needs the green bearings so it fits the rear housing. It won't fit with the adjuster in place.

 

[bc3j]

I may not be talking in the same context, but I used to race circle track cars in the 70's. Green Bearings were supposed to be the hot setup. We tried them and found them to be huge failure on the track. We would burn out a set during a night of racing. Went back to Timken bearings and never had a problem. Of course we were racing and I believe we're talking street use here, but from my experience, I would not use the green bearings.

 

[ramenth]

I may not be talking in the same context, but I used to race circle track cars in the 70's. Green Bearings were supposed to be the hot setup. We tried them and found them to be huge failure on the track. We would burn out a set during a night of racing. Went back to Timken bearings and never had a problem. Of course we were racing and I believe we're talking street use here, but from my experience, I would not use the green bearings.

Thus part of the never ending debate of green (sealed ball bearing...) vs. tapered. With the tapered's ability to take the side loads of the way the 8.75 is designed, the greens aren't supposed to last. There will be those who argue against this, saying they've run greens forever on the street. There will be those in the opposite corner, stating that they've had greens burn out quickly, even in street use.

Of course, one way around this, is to resize the axle ends and run Ford's roller wheel bearing set up.

 

[moparleo]

Correcto mundo Robert. Just the rears though, your pic has f&r shown.

 

[ramenth]

Correcto mundo Robert. Just the rears though, your pic has f&r shown.

I just scanned the net for pics to give the OP the gist. lol

 

[moparleo]

Can also upgrade and buy new axles with either bearing type from Moser, or the other axle mfg's.

 

[dfrazz]

Thanks for the input and suggestions. I would really like to keep the tapered bearings if possible and am a little disappointed that the description of the kit did not say anything about the requirement of the green bearings. Do you know of a power disc kit that allows you to keep the tapered bearings?

 

[bc3j]

I believe Dr. Diff sells a rear disc brake conversion that uses the 2004 vintage Mustang calipers and rotors. The kit has the adapter to mount to the mopar axle and retains the original axle bearings.

 

[Yatzee]

Some 8.75 with posi require the axles to have between .008 - .012 of lateral movement to unload the internal clutches as you turn a corner. Check the right axle to see if you have the adjuster (at the backing plate). If not use whatever bearings you wish. If the adjuster is there mods need to be carried out to use disks as the calipers will not tolerate any lateral movement of the axles. Internally the carrier has a pin that spans between both axle ends and moves the axles ever so slightly. Earlier this spring I saw an axle that had the pin fused right on to the end of one axle from heat because the owner forgot to set the free play.

 

[74 challenger]

Thanks for the info because I also was looking to do the rear drum/disk swap.

 

[Chryco Psycho]

I believe Dr. Diff sells a rear disc brake conversion that uses the 2004 vintage Mustang calipers and rotors. The kit has the adapter to mount to the mopar axle and retains the original axle bearings.

I agree He sells a kit that will work with the tapered roller brgs which I far prefer + Cass is great to deal with !