Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much slop?
 

So I took the risk and got a Traxxas 400 brushless servo+BEC for my TRX4 right when it was announced. It's been strong and reliable for the last month of hard runs in the challenging Southern California terrain but have noticed it has a good amount of play or slop. Is this normal behavior for a servo?

Here's a short video with the truck powered off: https://www.youtube.com/watch?v=LxCo...ature=youtu.be
Note the screw that holds the servo horn on is tight.

I also noticed a tiny lip on where the top case (where the output is) meets the metal mid-case piece. Does anyone else have one of these to confirm that's normal, or is my case bowing out due to stress and causing the internal tolerances to be less tight? My TRX4 is my first crawler and first RC in a decade so I'm not sure if this is one of those "don't overthink it" moments or not.

Here's that small bowed out area, complete with rusty stock screws :/
https://i.imgur.com/AuOLdDr.jpg

I know Traxxas electronics are controversial but damn. Seems like a good bit of slop for just over a month of use.

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

I would contact Traxxas,that looks like a product defect.Have you have the same problem with the plastic servo horn?

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

I haven't tried to mount the old horn yet but I'm gonna pull the servo and investigate. It looks like the whole servo output is wobbling from inside the servo, at least that's how it looks on the outside.


I ended up emailing Traxxas with the picture and video to see what they say. Noticed their press shots of the servo on Traxxas.com show a completely flush fit of all three case parts: https://traxxas.com/sites/default/fi...ed-on-trx4.jpg

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

Looks like play in the lower bearing and gears. Clearly that truck has been in water and left to rust/dry. From what I have seen and read the optional Traxxas servos are overpriced for what you get and what you have posted here just re-enforces that thought. Since there is not much history with those servos no one can say how long they should last but a little maintenance couldn't hurt. Ever considered spraying that thing down with WD40 when you're done playing submarine commander?

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

Imo stock servos are suposed to last long enough for shipping to send you a new one. Traxxas stock servos seem to be slightly better than axial stock servos, but still temporary junk. Spending the extra money for a good servo is worth it in the end. The promodelrs are great servos for the money.

There isn't much behind that bowing to cause that slop. More likly the servo horn teeth are worn.

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

That is not a stock servo. It is an over priced piece of crap but not stock.

OP I'd see what traxxas has to say about it, if they'll do a warranty exchange I'd do it and sell it to the next sucker and put something good in it.

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

I sent it off to Traxxas this morning, should know by about Thursday what they want to do with it. They said that I'm the first call with any issues with this servo and they want engineering to get their hands on it *shrug*. Apparently it's only warrantied for 30 days but the tech support dude sounded optimistic that they'd likely just take care of me on this one.

I ordered a Holmes SHV500 V2 servo to replace it in case this is a long wait. I hope they just swap me a fresh 400 servo and I can begin my second build with it, keeping the SHV in my Bronco.



The truck sees wet conditions for sure. It's my play toy for when I'm not working on my cameras or out working - of course it's gonna be run hard to the extent of at least the advertised features of the truck (waterproof!). That being said, I've been out of RC for over a decade prior to this truck and am ignorant to proper procedures here. I teardown, clean, and regrease the transmission, portals, and diffs every 8 or so runs, but can I really just spray the wet rig down with WD-40 and leave it like that for next time? I don't have a fancy compressed air tank or anything to clear it off.

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

Just an update here - Traxxas replaced this servo at no cost via RMA. I'll be running my Holmes SHV500V2 instead and slapping the Traxxas one into my next build (or maybe selling it for another SHV500!)

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

I don't do water much, but when I do I always spray it with air to blast off as much water as possible, then WD40 any metal parts, bearing faces, link pivots and CVD joints etc. Any place rust might form or might gum up from sitting. Works great for basic maint. between rebuilds. If you don't have a compressor, a can of compressed air for computers/electronics does fine.

Glad to hear they took care of you, especially for the price of that servo. Their support is usually pretty good. Did they ever say what happened to it? Just curious.

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

They didn't say - but they were very interested in the case as they kept saying they haven't had any RMAs or calls about the servo since launch. Just a quick "Replacing servo - thank you for choosing Traxxas" note in the RMA email. It looked like a failed bearing on the output shaft, but pretty odd that the casing was bowed out too so I wonder what the issue was. The casing was not bowed out when I installed it and I imagine the new one showing up tomorrow is going to be flush as well.

I'm at an impasse - I feel like I want to sell it off and get a more trusted servo. My SHV500v2 doesn't quite fit the mount in the TRX4 (Looks like I have to shave down the bumps in the mount and try to shove the screws in even though the holes don't line up, and get an extension for the receiver cable) so I'm tempted to throw it in and go crawling, but I also don't want to be in the same boat 30 days from now with a sloppy servo.

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

Yeah racing servo mount fixes that problem. As for your lead, just flip your receiver box 180° to get the wire opening to face the front.

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

Couple months later update: got my traxxas replacement about 15 packs ago and have been running it in the TRX4 since. It's had a couple high load/stall situations since it's been put in and while nothing has broken, this one has also developed an insane amount of slop. To the point where if you flip the truck and bump one of the front tires, it gets stuck in a centering loop where it wobbles left and right constantly trying to find center. The casing has not warped.

Do you think I can alleviate this with a new top case? This may be obvious for most, but I'd recommend anyone to avoid this servo.

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

Thanks for the update! Wow, I'd contact Traxxas again even though it's been couple months, that's unacceptable quality. If I paid that much for a servo that can stall frequently, develops that kind of slop (and can't find center) in a very short time span, I'd be not a happy camper. Good luck and keep us updated. "thumbsup"

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

I am having the exact same issue with my traxxas servo. Its terrible. Except mine has done the constant wobble back and forth since day 1. Thought that was normal lol. It's terrible quality for what I paid for it.

Re: Traxxas 400 Brushless Servo 2255 checking in, is there supposed to be this much s
 

I'm running Savox 1230SGs in all my rigs and some of them have in excess of 1000 hours run time and I have not had a single problem related to servos on any of my trucks. The 1230SG is a tad shorter than the odd sized Traxxas servos but that is not an issue. I simply file the opening in the servo mount holes on the side opposite the shaft and mount the servo on the raised bosses on the left side of the TRX4 servo mount. The right side of the TRX4 servo mount does not have any raised bosses so the servo sets flush. I use a 4" servo cable extension to connect the 1230SG to the RX. It's not a big deal.