TRX-4 Defender build notes

[danb1974]

Had an eye on this kit for a very long time. Finally a letter to Santa and it came true

For the Defender body, the 8057 short to long chassis conversion kit is needed (that I knew of) AND 8215 body posts (missed that one...)

Never build a Traxxas kit, some things are different, but I like them:

• I really like that each major stage has it's own bag and there are (almost) no extra parts making you wonder if you missed something
• Don't really complain of links and shocks coming preassembled
• Also no complains of parts coming already detached from part trees
• Radio pre-programmed; since it does not have a display and the bluetooth module is not included, this is a real plus

All in all, surpisingly pleasant build experience.

A few build notes:

• That's a lot of screws
• When tightening slipper, watch for spur wobble - easier to fix it at this stage
• Front portal input gears tend to rotate inside their bearings - a little grease fixes that
• Servos are labelled - I did not notice
• Wire routing for diff lock servos is a bit tricky since they have a "bulge" on the cable and there is little space between them and chassis. Beware of pinching the cables
• Due to extension kit, you'll need the two 3x12 screws that are normally used on battery tray on rear shock towers - no issue, you'll be left with two 3x10 to use on fixing the tray
• Extension kit instructions are a bit small, pay attention to rear shock towers orientation
• Really, that's a lot of screws, my right hand is filing a complaint as we speak

After chassis assembly I was left with two 3x10 screws, but can't figure out if they are extras or I missed something. Besides parts not used because of the conversion kit, these are literally the only extra parts left.

Question: according to manual, plastic to plastic and plastic to metal rotating parts are not greased (gearbox fork; pinion to spur). Is it wrong to grease them?

[mitch.douglas21]

Originally Posted by danb1974

Had an eye on this kit for a very long time. Finally a letter to Santa and it came true



For the Defender body, the 8057 short to long chassis conversion kit is needed (that I knew of) AND 8215 body posts (missed that one...)



Never build a Traxxas kit, some things are different, but I like them:

• I really like that each major stage has it's own bag and there are (almost) no extra parts making you wonder if you missed something
  
• Don't really complain of links and shocks coming preassembled
  
• Also no complains of parts coming already detached from part trees
  
• Radio pre-programmed; since it does not have a display and the bluetooth module is not included, this is a real plus
  

All in all, surpisingly pleasant build experience.



A few build notes:

• That's a lot of screws
  
• When tightening slipper, watch for spur wobble - easier to fix it at this stage
  
• Front portal input gears tend to rotate inside their bearings - a little grease fixes that
  
• Servos are labelled - I did not notice
  
• Wire routing for diff lock servos is a bit tricky since they have a "bulge" on the cable and there is little space between them and chassis. Beware of pinching the cables
  
• Due to extension kit, you'll need the two 3x12 screws that are normally used on battery tray on rear shock towers - no issue, you'll be left with two 3x10 to use on fixing the tray
  
• Extension kit instructions are a bit small, pay attention to rear shock towers orientation
  
• Really, that's a lot of screws, my right hand is filing a complaint as we speak
  

After chassis assembly I was left with two 3x10 screws, but can't figure out if they are extras or I missed something. Besides parts not used because of the conversion kit, these are literally the only extra parts left.



Question: according to manual, plastic to plastic and plastic to metal rotating parts are not greased (gearbox fork; pinion to spur). Is it wrong to grease them?

Only thing I would add on is, if your planning for heavy water or dusty dirty use do your self a favor now and get 3 in 1 dry lock or something similar. Coat all your screw heads with it, this will help prevent dirt getting in the hex which if not cleaned out can cause it to strip out easy. (I know it sounds dumb but these are really easy to do that, I learned the hard way)

Also, if you want to lube or grease those gears, cables, forks, shock body threads anything that needs to slide, rotate that can get dirty i would also use the dry lock on as well. Gives enough lubricant, and keeps dirt out and will keep stuff from getting rusty if your in water. Do the motor brushes as well but don't over do it, the stock motor will burn up in heavy water abuse (when the truck is swimming at full throttle) this helps keep the brushes clean and just add some between runs.

Sent from my Pixel 3 XL using Tapatalk

[danb1974]

For now it's indoor only, want to keep it clean but also minimal gear noise

Two more notes:

• Do not mix up threadlock coated screws (steering servo and pinion) - nice touch traxxas
• Beware of pinion position, a tad to the back and the screw will scratch the spur at each rotation

Any ideea where I can order scale accessories with combined shipping, or sold as sets (things like barrel, box, shovel, luggage net etc.)

[mitch.douglas21]

Originally Posted by danb1974

For now it's indoor only, want to keep it clean but also minimal gear noise

Two more notes:

• Do not mix up threadlock coated screws (steering servo and pinion) - nice touch traxxas
• Beware of pinion position, a tad to the back and the screw will scratch the spur at each rotation

Any ideea where I can order scale accessories with combined shipping, or sold as sets (things like barrel, box, shovel, luggage net etc.)

You can get those from many places. Ebay, amazon, local hobby shops, shape ways and other 3d printed sites and more. Rc4wd has some as well

Sent from my Pixel 3 XL using Tapatalk

[danb1974]

Having a faint clicking in the high gear. Before I take apart the gearbox... anybody else had that?

[OSRC]

Originally Posted by danb1974

Question: according to manual, plastic to plastic and plastic to metal rotating parts are not greased (gearbox fork; pinion to spur). Is it wrong to grease them?

I coat everything that rotates, and even some things that don't....bearing pockets, gear shafts, bearing faces - it all gets a light coating of grease. I use a light Penzoil grease for plastic on plastic and Red and Tacky for metal gears.

The only thing that should not be lubed up is the shift fork for the diff unlock in the axles. Seems to clog up the fork for some reason.

[xagoras]

Originally Posted by danb1974

Having a faint clicking in the high gear. Before I take apart the gearbox... anybody else had that?

If you mean a ''click'' sound right after you switch gears, as you press the throttle, it probably comes from the gear servo as it gets into position.

[Benp]

Even though my trans is single speed, I have a faint ticking that’s rpm dependent.

I’m attributing it to the driveshafts are out of phase from the factory.

Transmission tear down and re-do is on my to do list.

[M_Saint]

Originally Posted by Benp

Even though my trans is single speed, I have a faint ticking that’s rpm dependent.

I’m attributing it to the driveshafts are out of phase from the factory.

Transmission tear down and re-do is on my to do list.

Double check and make sure the grub screw in your pinion isn't hitting the spur.
That grub screw is right up against the side of the pinion teeth.
I had the same noise and had to move my spur gear front on the shaft a little farther.

[Benp]

Originally Posted by M_Saint

Double check and make sure the grub screw in your pinion isn't hitting the spur.
That grub screw is right up against the side of the pinion teeth.
I had the same noise and had to move my spur gear front on the shaft a little farther.

Thanks!

I’ll check that out

[ScaleLifeNewbie]

Originally Posted by M_Saint

Double check and make sure the grub screw in your pinion isn't hitting the spur.
That grub screw is right up against the side of the pinion teeth.
I had the same noise and had to move my spur gear front on the shaft a little farther.

Yep, that’s happened to me a few times. Very annoying when out on the trail and all you hear is ticking lol.




_________________
SCX10 ii
TRX4

[M_Saint]

Originally Posted by M_Saint

Double check and make sure the grub screw in your pinion isn't hitting the spur.
That grub screw is right up against the side of the pinion teeth.
I had the same noise and had to move my spur gear front on the shaft a little farther.

Actually that should have read "I had the same noise and had to move my pinion gear front on the motor shaft a little farther" but yous got the jist

[Inspector86]

OP post pics of your rig, in case you hadn't noticed we love pics.

[danb1974]

Had the "pinion screw hitting spur" right after build, fixed at that time. What's left is a constant speed dependant faint clicking only while driving in high gear (not the gear change noise).

Oh, yeah, pics, sure. Most are before the scale accessories arrived, while I was exploring various "how did I got into this position" moves.

Hint: put different size empty boxes under the rug for a bit of indoor fun.

[danb1974]

So, had this faint transmission clicking for a while, audible in high gear. Getting caught with other things and ignored it, until now.

Good news, not the gearbox. The noise came from the shafts, especially the front shaft. Well, not the greatest shafts and no grease on them - until I noticed the front axle going not as smooth as the back axle.

No time today to tear it apart but loosening and tightening back the diff cover screws made things a lot better. Noise (almost) gone under no load.

Not the first car on which the diff housing causes issues. Should have checked more carefully during the build. In my defense I was on a sort of schedule.

[danb1974]

Not to start a flame war... how satisfied are you about your trx4 in stock form? Compared to how other stock crawlers perform.

Except the weak servo (which does not even require a saver, since it cannot break anything, lol), giving the high cog, I am pretty much impressed - but I only had a modded scx10 some years ago. Handles well and does not "jump around" as lighter crawlers tend to do. Just not a fan of how the front CVDs perform under high angle but that's how a single joint cvd is.