Dry gears? Yay or nay?

[KnowAir]

My Xmaxx is coming up on 3 years old, been a great truck. Recently it started clicking, I haven't opened a diff on it ever. Well, turns out the rear pinion lost a couple teeth. No suprise or disappointments, I bought new ring/pinion and bulkheads. When I took it apart, everything had a healthy coat of grease, which was also full of dirt/sand. So, being the gearbox clearly doesn't seal, what does everyone think about assembling it dry? Is the "grinding paste" (@Horatio ) really helping or hurting the gears?

 

[Sandracer_NL]

Although you could get a grinding paste I always use grease. I use way less grease than I used to though; only filling the gaps between of the gears’ teeth.
You’ll probably won’t get a 100% seal, but new diff and input gear bearings or a new bulkhead usually reduce the sand problem a lot. Another cause is a gap between the chassis and bulkhead; bent chassis, chassis flex or bulkhead/chassis screws that are not tight enough. You could use gearbox gaskets or a liquid gasket from the hardware store.

 

[KnowAir]

Although you could get a grinding paste I always use grease. I use way less grease than I used to though; only filling the gaps between of the gears’ teeth.
You’ll probably won’t get a 100% seal, but new diff and input gear bearings or a new bulkhead usually reduce the sand problem a lot. Another cause is a gap between the chassis and bulkhead; bent chassis, chassis flex or bulkhead/chassis screws that are not tight enough. You could use gearbox gaskets or a liquid gasket from the hardware store.

Makes one wonder, LOL. How the heck does that sand get in there and turn grease into grinding paste? I've seen loose bulkheads on Arrma/TC rigs, where the gearbox screws have loosened up and allowing the gearbox to lift off the chassis plate. With the Xmaxx that's not where it's getting in, not sure where/how, but it sure did. I suppose that's why they call it "routine maintenance", LOL.
I did assemble the Xmaxx dry, ran a pack through it, surprisingly quiet. On the fence about just opening the covers and putting a dab of "paste" in there. Hate to be "that guy" who thought he knew more than anyone else..

 

[KnowAir]

Oh yeah, I almost forgot to mention, since I'm too lazy/cheap/impatient, I knew the bearings needed replacement, but they hadn't actually fallen apart, yet. So I brushed the dirt/paste off the outsides, popped the seals and gave each a couple drops of Barney purple oil (Acer Sin Lube), a slathering of high tack paste, popped the seals back in and reinstalled them. Cowboy style, LOL. Truck seems to really roll out now, LOL.

 

[Sandracer_NL]

Oh yeah, I almost forgot to mention, since I'm too lazy/cheap/impatient, I knew the bearings needed replacement, but they hadn't actually fallen apart, yet. So I brushed the dirt/paste off the outsides, popped the seals and gave each a couple drops of Barney purple oil (Acer Sin Lube), a slathering of high tack paste, popped the seals back in and reinstalled them. Cowboy style, LOL. Truck seems to really roll out now, LOL.

I also use the ‘cowboy style’ your refer to when I’m lazy. Often leads to ordering new part(s) on pretty short notice.

 

[Niekname]

I am guilty of that myself, they are still running tho.

I always wonder if more grease might actually be beneficial to minimize grinding paste. Like the grease that gets flung off the gears catches the majority off the dirt. No idea if that is true though.

I think the biggest issue with running dry is the heat build up. And also because these gears are cut differently then e.g. spur and pinion. Which apparently matters in some way in relation to greasing. Thats what I have been told at least no idea why that is.

 

[Sandracer_NL]

I am guilty of that myself, they are still running tho.

I always wonder if more grease might actually be beneficial to minimize grinding paste. Like the grease that gets flung off the gears catches the majority off the dirt. No idea if that is true though.

I think the biggest issue with running dry is the heat build up. And also because these gears are cut differently then e.g. spur and pinion. Which apparently matters in some way in relation to greasing. Thats what I have been told at least no idea why that is.

Yes I also think some grease in the bulkhead corners can ‘catch’ sand. It makes cleaning the bulkhead an even more messy job, so I prefer to mitigate the cause of the sand entering the bulkhead instead. Not always easy though.

 

[KnowAir]

I am guilty of that myself, they are still running tho.

I always wonder if more grease might actually be beneficial to minimize grinding paste. Like the grease that gets flung off the gears catches the majority off the dirt. No idea if that is true though.

I think the biggest issue with running dry is the heat build up. And also because these gears are cut differently then e.g. spur and pinion. Which apparently matters in some way in relation to greasing. Thats what I have been told at least no idea why that is.

I have thought similarly, I mean the evidence is right there, stuck to the grease in the gearbox, lol.
Angle of the dangle, I mean gears. You may very well be right on that.

 

[KnowAir]

Yes I also think some grease in the bulkhead corners can ‘catch’ sand. It makes cleaning the bulkhead an even more messy job, so I prefer to mitigate the cause of the sand entering the bulkhead instead. Not always easy though.

I have used grease along the base of the gearbox where it meets the chassis, even silicone, as well as around the lip of the covers in the past. Never really sure if it worked or not, seems to help. The Xmaxx is a bit different in construction though. I think the front and rear gearboxes are pretty well sealed, but the counter or jackshaft that engages with the center diff gear, that area doesn't seem very well sealed. But, at 3 years old and the original gears still holding maybe wise to just do as Traxxas did? Clearly not a bad setup. I'm going to open it back up a slab some red paste in there. LOL.

 

[Sandracer_NL]

If it worked for 3 years I’d say don’t try to change it!

 

[Niekname]

Especially without shimming. Maybe after a couple runs when your new gears are bed in shim them and they will last even longer.

 

[Horatio]

Bit late to the party - but yeah - definitely use grease on metal to metal gears. It amazes me how dirt finds it's way in. Or how cables merely placed on the floor manage to tie themselves into a knot. I'm fairly certain that RC is not exempt from high strangeness/supernatural.

Your gear cases must have gaps, or cracks, or both. Possibly poltergeists. So really, I guess it's cheaper in the long run to seal em' up, rather than perform exorcisms.

If sealing up the cases fails, I've added a link to book an exorcist, just in case.

Book an exorcism

 

[Sandracer_NL]

 

[Horatio]

Before ^

After:

Depending on the application, I use Mugen Supergrease (very conservatively - it's sticky) and Comma Multi Grease which seems to work well on just about everything, although it's thinner and doesn't cling like the Supergrease.

 

[Horatio]

Here's a shot of a traumatized 3 speed transmission. It seems to have swallowed something at some point - over the past 20 years.

So sometimes - you just have to start again....

 

[KnowAir]

I caved, opened up the counter shaft cover, rear diff case, and added a dab of red HT. LOL. A dab will do. Thanks fellas!
Oh, and I applied the thinnest bead possible around the rear gearbox cover for good measure

 

[Horatio]

I caved, opened up the counter shaft cover, rear diff case, and added a dab of red HT. LOL. A dab will do. Thanks fellas!
Oh, and I applied the thinnest bead possible around the rear gearbox cover for good measure

No exorcist required then?

 

[KnowAir]

No exorcist required then?

Maybe if the new pinion loses a couple teeth straight away..

 

[Trucking in space]

Bit late to the party - but yeah - definitely use grease on metal to metal gears. It amazes me how dirt finds it's way in. Or how cables merely placed on the floor manage to tie themselves into a knot. I'm fairly certain that RC is not exempt from high strangeness/supernatural.

Your gear cases must have gaps, or cracks, or both. Possibly poltergeists. So really, I guess it's cheaper in the long run to seal em' up, rather than perform exorcisms.

If sealing up the cases fails, I've added a link to book an exorcist, just in case.

Book an exorcism

Poltergeists are generally the cause of most household havoc, including (but not limited to) throwing stones, raps and thumps on walls, scratching on walls, setting small fires, moving \ removing various objects as well as "apports" (the teleportation of new objects of unknown origin into the home)

Poltergeists are so well-known for stone throwing that it's in their name polter-geist, German for "pelting ghost"

Extra troublesome poltergeists may break furniture \ glass, cause pools of water to appear, or even attempt to harm humans (stabbing with knives or forks, causing burns or cuts on the body without a visible cause.

However, in 9 out of 10 cases, the damage is limited to furniture and household objects.

Also, generally, poltergeists are very violently reactive to exorcism attempts, as they are not demons (most of the time).

Instead, poltergeists are usually found to be attached to a teenage or pre-teen human, more commonly female than male.
If this "host" person leaves the property, the disturbances will follow the affected person.

I did a high school report on poltergeists.
Got an A-

The best book on the subject (written by a guy who was previously a skeptic until his meetings with various "haunted" families: "Poltergeists: A Study in Destructive Hauntings" by Colin Wilson.

Top notch book. Great author. Cheers ! (And don't play with Ouija Boards)

 

[Horatio]

Poltergeists are generally the cause of most household havoc, including (but not limited to) throwing stones, raps and thumps on walls, scratching on walls, setting small fires, moving \ removing various objects as well as "apports" (the teleportation of new objects of unknown origin into the home)

Poltergeists are so well-known for stone throwing that it's in their name polter-geist, German for "pelting ghost"

Extra troublesome poltergeists may break furniture \ glass, cause pools of water to appear, or even attempt to harm humans (stabbing with knives or forks, causing burns or cuts on the body without a visible cause.

However, in 9 out of 10 cases, the damage is limited to furniture and household objects.

Also, generally, poltergeists are very violently reactive to exorcism attempts, as they are not demons (most of the time).

Instead, poltergeists are usually found to be attached to a teenage or pre-teen human, more commonly female than male.
If this "host" person leaves the property, the disturbances will follow the affected person.

I did a high school report on poltergeists.
Got an A-

The best book on the subject (written by a guy who was previously a skeptic until his meetings with various "haunted" families: "Poltergeists: A Study in Destructive Hauntings" by Colin Wilson.

Top notch book. Great author. Cheers ! (And don't play with Ouija Boards)

Well, it's funny you should say that. I believe that there's a poltergeist inside my laundry room that eats socks.

Joking aside, back in 91, I lived in the annex of a Mansion. We had friends stay over that had, unbeknown to us, been 'dabbling' with Ouija boards.

After they left, in the early hours of the morning, an Onyx box on the window sill made a loud 'bang' - it had fallen apart - all the sides of the ornate box were basically now laying down.

An hour or so later, around 4 am, loud banging could be heard from the airing cupboard. It initially sounded like a creature - a bird or bat - flapping and crashing around. My Fiance was absolutely terrified - so now armed with a bat - I went to the airing cupboard. Placing my hand on the door, whatever was making the noise was now pounding on the actual door - more like a human thumping by this point. It was mental.

The very moment I flung the door open - silence. Nothing there at all. Poof - gone. It was a sealed cupboard with no gaps and a heater, with wooden rungs.

The following day, I described our experience to our friends that had visited. They were gobsmacked - because the same night they had been playing with a Ouija board around the same time and their pint glass had exploded.

Needless to say, they stopped messing with it and thankfully, the high strangeness stopped.

There's another experience I could share, if people are interested.