Newbie Diff Questions

[jlvhawk3]

Please forgive me, first time really getting into the diffs on my Granite BLX 3s and have some questions. I got a set of the Fast Eddy sealed bearings when I noticed that one of the wheel bearings had basically exploded. I replaced all the wheel and axle bearings, and now getting into the ones in the diff. A few questions as I'm working on that, see the picture below for clarification to match what I'm talking about with question # since I'm not sure the proper name for everything...

1. Is there a trick to getting this bearing off? This one seems to be on there %^$@ing tight! I got it off the rear diff only after I exploded the thing trying to pull it with some channel locks. I can pry it a couple millimeters by getting a flat screw driver between the bearing and the gear side, but haven't found a good way to get it off the rest of the way.

2. This washer, I don't seem to have it under the bearing(s?) that fits into the yoke set. I replaced both of those bearings and didn't see a washer under either one of them. Based on the picture, am I seeing correctly that it is just supposed to be on the one side? Do I need to order and put one in? I honestly can't really tell what it would be needed for there unless it's just to prevent rubbing?

-- Speaking of the yokes, is there a right and wrong side for these to go on? I can't seem to tell much difference in the 2 sides and trying to make sure I have them back on right.

3. I assume the grease in these gears is where I want something like what is labeled "diff grease"? Is there a specific requirement for this grease? I only ask because I happen to have some of the Lucas red n tacky (and some other greases from non RC use) that there is a current thread on being a high quality grease. Would a bit of that work here or do I need something different?


Thanks for helping out a new guy!

 

[adidas303]

1. I always use a flat head screw driver to PUSH the bearings out, from the opposite side. Push a bit from the top and wedge it loose some then do the same at the very bottom, then left/right side and continue around until it finally pops out. If you can't reach it from an opposite side, then as carefully as you can, you would hit the same four opposite areas to pry the bearing away/off the input gear as evenly as possible.

2. Those are referred as Shims. They will just fill up space and gaps left/made from the stock parts. Sometimes both sides needs it, sometimes only one. In this setup it looks like the one shim is all that needed.

3. So the RedNTacky grease is good for giving light coats of grease on say the Ring and Crown gear meshing. The parts you have the Red connecting. Verify per your manual if your Differential Cup, AR310872, is sealed. If it is sealed, that is what you use the weighted Diff Oils for, 50k, 100k, 500k weights.

I apologize as I'm not sure if the yokes are universally used on either side with that specific model.

 

[jlvhawk3]

1. I always use a flat head screw driver to PUSH the bearings out, from the opposite side. Push a bit from the top and wedge it loose some then do the same at the very bottom, then left/right side and continue around until it finally pops out. If you can't reach it from an opposite side, then as carefully as you can, you would hit the same four opposite areas to pry the bearing away/off the input gear as evenly as possible.

2. Those are referred as Shims. They will just fill up space and gaps left/made from the stock parts. Sometimes both sides needs it, sometimes only one. In this setup it looks like the one shim is all that needed.

3. So the RedNTacky grease is good for giving light coats of grease on say the Ring and Crown gear meshing. The parts you have the Red connecting. Verify per your manual if your Differential Cup, AR310872, is sealed. If it is sealed, that is what you use the weighted Diff Oils for, 50k, 100k, 500k weights.

I apologize as I'm not sure if the yokes are universally used on either side with that specific model.

Thanks!

I basically tried your method with the bearing on the input gear, but still quite the pain! Oh well, hopefully it shouldn't need to come off often! As for the shims, would there be a reason it might have been left off mine? Slight manufacturing tolerance or something just didn't require maybe? Sounds like I'll go ahead and use some grease I have on those gears. I haven't actually taken the diff cup apart yet. I'll have to check on if that's sealed. Just now realizing there's a bearing in there that probably has a replacement in the Fast Eddy kit I picked up.

 

[adidas303]

In all honesty it probably was forgotten, possibly they just didn't need it. Definitely don't want to over shim parts as that can create a bind point.

If you drive a lot in wet areas or very sandy areas, beaches, the bearings will need replaced a bit more often. Ceramic is not needed for bashing, waste of money. Definitely swoop up some Sealed Bearings though, whether through Fasteddy or different place! I know for sure Fasteddy Bearing kits will come with all bearings needed, even the steering linkage area. You want to replace the bushings in the steering with bearings. They will not come with bearings for the motor though.

It would probably be easiest for ya to do the Diff and Bearings at the same time if possible. You'll have to take apart most of the front and rear end to replace those bearings, might as well then do up the Diffs with everything out already and easier to remove and replace at that point!

? ?

 

[jondilly1974]

Please forgive me, first time really getting into the diffs on my Granite BLX 3s and have some questions. I got a set of the Fast Eddy sealed bearings when I noticed that one of the wheel bearings had basically exploded. I replaced all the wheel and axle bearings, and now getting into the ones in the diff. A few questions as I'm working on that, see the picture below for clarification to match what I'm talking about with question # since I'm not sure the proper name for everything...

1. Is there a trick to getting this bearing off? This one seems to be on there %^$@ing tight! I got it off the rear diff only after I exploded the thing trying to pull it with some channel locks. I can pry it a couple millimeters by getting a flat screw driver between the bearing and the gear side, but haven't found a good way to get it off the rest of the way.

2. This washer, I don't seem to have it under the bearing(s?) that fits into the yoke set. I replaced both of those bearings and didn't see a washer under either one of them. Based on the picture, am I seeing correctly that it is just supposed to be on the one side? Do I need to order and put one in? I honestly can't really tell what it would be needed for there unless it's just to prevent rubbing?

-- Speaking of the yokes, is there a right and wrong side for these to go on? I can't seem to tell much difference in the 2 sides and trying to make sure I have them back on right.

3. I assume the grease in these gears is where I want something like what is labeled "diff grease"? Is there a specific requirement for this grease? I only ask because I happen to have some of the Lucas red n tacky (and some other greases from non RC use) that there is a current thread on being a high quality grease. Would a bit of that work here or do I need something different?


Thanks for helping out a new guy!

View attachment 66913

1) The inner bearing on the input gear is the one I always struggle with. Has taken up to 10 mins to persuade it to come off. Flathead screwdriver and a pair of needle nose pliers are what I use.

2) If you are missing the shims, I would buy a set and see if the diff feels good or bad with them. You won’t know if you don’t have them on hand.

Yes yokes have a side. If you assemble them backwards they won’t fit back in.

3) I use sil-glide brake grease, but RnT would be fine. Marine grease works for others too.

 

[Matt6453]

I did all mine but left the stubborn bearing you mention on each pinion, I figured it's the one inside the case and isn't exposed to dirt and moisture so there was little point in replacing it.

 

[jlvhawk3]

Thanks for the help guys! I finally found a good way to get that stubborn bearing off. Had a one of the thin wrenches that came with one of my saws that is for tightening the blade, happens to fit around the plastic part but still smaller than the bearing. After I used the screwdriver to pry the bearing enough to get that wrench in there, set the metal part on the ground and used a hammer to tap the wrench and push the bearing down. Worked amazingly well! Maybe that will help someone else out too.