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New steering servo... anything else?

Fifty

Newbie
Joined
Apr 5, 2020
Messages
38
Location
Bay Area
I just got my trx-4 defender yesterday. I heeded all of the warnings about the stock steering servo. And fortunately or unfortunately I bought the traxxas 400 brushless servo at the same time.
I say unfortunately because I am now learning that their are better Servos for roughly the same price. But anything is better than stock as I have found out after three batteries worth of driving today. The steering does really stall out with anything over a little bit of of angle weight on the front end. I didn’t think it would be that obvious. (I also got the ebc or what ever that was called for with this new servo).

I also got the Hot racing aluminum steering arm and aluminum steering servo mount. (The Mount was in the basket and I didn’t check before I hit order).

I am wondering, while I have the truck apart to run the wiring and install the servo and the mount, are their any other upgrades I should do while I have it apart?

I figure if I have it apart and there is a known improvement part, like a stronger drag link or what ever, it’s best to just get it done while that part is apart.

Any recommendations?
 
Sure there are better servos out there but like you said... almost anything is better than the stock unit. It's not just under-powered but they have a pretty high fail-rate as well. Even if you could've lived with the lackluster performance, it likely will/ would've crapped out soon anyway. Good choice for first upgrade.

Maybe someone else can chime in with some things that I'm not thinking of but imo you did good not going overboard. A lot of ppl tend to throw parts at the trx4 ( partly b/c there's so many after-mkt parts out there) before really getting to know their vehicle. I'd drop in that new servo/ arm/ mount and run it until you think you see something that needs addressed. Maintenance and tools are a good place to spend money at this point.

I would recommend taking a look at things like making sure screws are in place/ torqued properly... Making sure that driveshaft set-screws are in place and tight, etc... concentrate on steering/ axle/ drive-line/ suspension components... just to make sure all looks well.

Additional consideration might be nailing down what batteries ( regarding connectors... deans, xt60, traxxas, etc) you're going to want to use. And make sure that your charger is adequate and compatible in order to streamline that aspect.
 
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I appreciate it. I went with the Amains traxxas dual charger with dual 3s batteries.
Just kept it simple.
At least I knew their wouldnt/shouldn’t be any issues.

The only other hiccup I’m having is shocks not controlling the wheels/tires in high gear. But it is a crawler and it’s not the end of the world.

I will eventually look at a way to find a little extra droop and a better front bumper. (For the type of wheeling I’m doing with it)
 
Gotta agree with hpd, the new servo is a good idea, the stock ones don't seem to hold up. Most of us add a little weight low down. Things like heavy portal covers seem to help a good bit. But like he said, drive it some and see what mod's will help with your terrain of choice and your driving style. There're a lot of choices for upgrades, but they're not all as "helpful".
Mostly have fun with it, and post up the changes you do make and the results you get. "thumbsup"


8) jim
 
Roger that! Hope to do the servo and mount tomorrow if everything works out free time wise!

So far after one day. It’s just steering lol. And then because it’s a back yard toy, I have some space and a neighbor has moooore space. It’s home built obstacles. A lot f junk crawling so to speak. But in between there is a bit of high gear offroad cruising

So stock gearing with a 3s battery and the tire control is not so great. A quick search shows their isn’t too much improvement shock wise over what’s on it.
So I’m wondering if it’s a travel issue and not a shock issue. Or a weight issue.. who knows.

I’ll keep driving it for the next two weeks with the new servo and see if the shocks break in (these come with oil already in them right lol... sorry, I’m used to real coilovers and bypasses etc etc) Before I invest in any changes.
 
The shocks are oil filled but there's a lot that you can do to tune them... increasing/ decreasing spring rates and oil weights being a popular modification. The trx4 stock shock is actually one of the better shocks out there. You can also play with preload ( spacers) too. In time, you should start to develop a good feel for the weight and handling characteristics of your particular rig and subsequently what improvements you want to make in order to dial in the suspension.
 
A higher weight to slow high speed compression may help. I’ll search what stock oil weight is
 
One of the issues with a higher power servo is that it draws more amperage. The problem is that the stock XL5 ESC is only rated at 1a output. This may cause power brownout issues while driving. A very popular upgrade is the HobbyWing Quickrun WP1080 ESC which is rated at 3a output and is able to drive the higher power servo without the need to install an external BEC. The HW 1080 can be purchased for $42 at places like RPPHobby.com. Do not waste your money on the Traxxas BEC it is output rated the same as the HW1080 for nearly the same price and no performance benefit.

As for shocks, the Traxxas GTS shocks are considered some of the best on the market but they do need some tuning. Traxxas offers a range of spring rates and there are different weight shock oils. Typically I run 10wt shock oil and the Traxxas .30 springs with no pre-load in other words adjusted so the upper retainer is just touching the spring but not compressing it. Also, with the springs off there is a small plastic cap on the shaft end of the shock body which is an X-ring retainer. A small amount of Green Slime or any silicone grease on the X-rings then reinstall the cap leaving it about 1/4 turn from full tight will really smooth out the shock action.

All this is just the tip of the iceberg so to speak. There are an endless number of upgrades, mods and aftermarket parts that you can play with as you become more familiar with your TRX4.
 
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Dang . I already got the traxxas bec when i ordered the traxxas 400 servo. It was part of the suggested list on amain website...
 
Dang . I already got the traxxas bec when i ordered the traxxas 400 servo. It was part of the suggested list on amain website...


The problem with the Traxxas BEC is that it is non-adjustable and is rated at 3a 6v for nearly the same price as the HW1080. The HW1080 has smoother throttle control, is programmable and runs cooler than the XL5. In short the HW1080 is just a better ESC and it works surprisingly well with the stock Titan 550 21T motor. So Sorry to hear to bought the Traxxas BEC but to be honest I would toss it in the spare parts box and buy the HW1080 ESC it is that much better.
 
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You may as well run what you have. The stock receiver and micro servos don't like more than 6 volts. More than that will start to burn up the stock electrics. I run a 1080 in my rig, but I keep the bec at 6v to run all of the other electrics. I power my steering servo with an older Castle 5 amp bec. Since you already have the stuff, run it 'til it fails or you feel like you need to upgrade. Again, what you'll want to improve depends a lot on where and how you drive it. ;-)



8) jim
 
So much has changed in 20’years...

Last time I had an RC car, electronic speed controllers were becoming affordable. There was none of all this stuff. So steep learning curve
 
If you don't try turning the wheels stationary the stock servo is pretty good. Mine lasted 18 months of regular distance trails and crawling every weekend. People only ever talk about the negative and not the good stuff seemingly. When you look at the thousands of trx4s sold I wonder how many in a percentage have failed that quickly.
 
I agree with the goods vs bads. I’ve had a ton of fun lol! To me the only bads that I have found are the shock valving and the steering.

I have found that in my use the steering is dull and stalls. And then the shocks don’t control very well when I’m buzzing around.

I’m going to wait and see if the shocks break in some and then if not changing the shock oil weight. I wish there was an easy way to see if the suspension is bottoming out or if it is just too stiff spring wise. Both opposite ends of the spectrum but will give the same driving responses.

I can try lighter springs cheaply and easily. Oil change is also inexpensive but more labor intensive toe bleeding, especially if the effects are bad.
 
You can put a little grease on the shock shafts and it should show you how much the shocks compress by how far it wipes off. Or if you have small o-rings to use as a marker. Even dust or graphite powder. :)



8) jim
 
Grease is a good idea. I’ve got a bunch of red bearing grease that will show good.
I’ll try that tomorrow. (I was trying to think of If a small bushing would stay if I cut it to put it on
 
On the shocks, have you tried loosening the cap on the bottom of the housing? Just a 1/2 turn or so would help. When the cap is tightened all the way, it compresses the O-rings too tight against the shaft. By loosening the bottom cap, you release some of the pressure and allow the shaft to slide easier.
 
RC has evolved so much in 20 years!

If you can, return the Traxxas servo and BEC.
You can get much better for your money. It is nice Traxxas offers everthing plug and play. That way newbies can upgrade without having to solder.


The problem with the Traxxas BEC is that it is non-adjustable and is rated at 3a 6v for nearly the same price as the HW1080. The HW1080 has smoother throttle control, is programmable and runs cooler than the XL5. In short the HW1080 is just a better ESC and it works surprisingly well with the stock Titan 550 21T motor. So Sorry to hear to bought the Traxxas BEC but to be honest I would toss it in the spare parts box and buy the HW1080 ESC it is that much better.

I agree. The 1080 was one of the first mods I did to my TRX-4. The internal BEC really woke up the stock servo. I ran it until it munched the gears and then I upgraded the servo too.
 
You may have clearance issues with the hot racing servo arm. I tried an aftermarket steering arm and it wasn't the right length and interfered with the panhard when the suspension was compressed. I would recommend the Traxxas metal servo arm. I stripped my stock plastic one the first outing in rocks.
 
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