Let's keep the noise down.

[jjbigfly]

Regarding the Axial Coyote and SR5.....Discovered a different way to set gear lash. Different for myself at least. And then the BONUS trick....after the gear lash.
The SR5 is fairly easy to use this method. I set the SR5 on the stand and installed a battery. I then removed the TOP most screw FIRST on the spur gear cover, then the lower one. If you do it the other way your portal bearings will turn orange and you may develop an eye twitch, but I digress.......Just take the damn thing off, alright? I used a flex shaft to loosen the motor holding screws. ONLY slightly loosen the motor screws so you can barely move the motor (I use a small screwdriver to pry with). Set the throttle to about half speed and move the motor as little as you can as the motor is running. It can scream or growl at you, but when it starts to whisper it should be perfect. Really. When it seems right, tighten the motor screws (while it's still running if you are able. IF you hear a change then make a very slight adjustment to the motor. Not nearly as difficult as it sounds and it works! I really want my rigs to be quiet and am getting proactive.

The next trick? I got it outside to test and it was super quiet (well, quieter than it was). Put the gear cover back in place and a good deal of gear noise came back! Big Difference. I ended up cutting the face of the gear cover away, leaving the "rim" as a rock guard (sorta). I am planing to fit some sort of cover over the rim, but I have crawlers with no protection at all and have yet to have an issue (but I never do mud) with the gears.

Or....adjust the gear lash while the motor is running and leave the cover off......but that is not nearly as impressive as a long detailed explanation.
Does crawling affect thought process?

 

[C life]

I usually set it static, using the spur gear I rock it slightly back and forth just until I get the smallest amount of play possible between the spur gear and pinion. I've also noticed if you don't use a good hardened steel pinion it will be a noisy mesh. Sounds like what you are describing is interference from the gear cover. Look at the inside of the cover for marks. If you see some maybe sand them out with a dremel.

 

[jjbigfly]

I usually set it static also, but getting carried away with noise control . There are no marks inside the gear cover at all. Thinking gear noise is from the trans and the gear cover is making it resonate. While I did not mention it, I lined the inside of the cover with servo tape and I still had clearance but I still had noise. But with the cover off it is quite a bit quieter.
My Coyote seems to be the same with or without the cover. But it was quiet anyway. Now it sounds like a Tesla.....Only differences I can think of is the SR5 (noisy one) has a DIG but that should not cause any noise. The Coyote has been lubed with white lithium.
I should mention that these rigs are pretty normal sounding when compared to other crawlers, I just want it quieter because I'm Weird. Could be the age thing. I am supposed to be in the golden years but I am running late or I am simply not old enough to qualify. Damn! I really thought 79 would work. Should be soon though. I will keep playing outside for now......

 

[Doom!]

If you fill that housing with grease it quiets it quite a bit.