Simple Upgrades Traxxas TRX-4

What's up guys?  Today we're going to check out some simple performance upgrades for the Traxxas TRX-4.  Now the TRX-4's have become extremely popular since their release and they offer a lot mechanically; with the two-speed locking differentials, cruise control, and more but they come with one slight disadvantage and that is the trucks are kind of top heavy.  With a crawler you want most of the weight down low, with the idea that the if the truck is going to get sideways it's not going to upset.  The issue with a lot of that weight being up high on our TRX-4 models is that they will tip over a little bit easier and also with a lot of the weight being in the back with the spare tire and the extra accessories, they tend to be a little bit rear heavy as well.  That said, the upgrades in this article are going to be based around the idea of weight...

How to Eliminate it Up High and How to Get More Down Low.

#1 - Lower Weight Battery

The first upgrade we're going to talk about is going to be the battery. When most people think of rigs like this they think "well let's use a big stick pack it has a lot of milliamps, it'll provide a really long runtime!" That is true, more milliamps, more run time and for crawlers that can be in the hours, but you don't have to run a battery like this. Having a stick battery up high, right in the center, that's a lot of weight up there. Instead, you have the option of using Traxxas Mini LiPo's, offered in two different types;* the 3-cell 1400 milliamps and the 2200 milliamp. Both fit really, really well in the recessed area of this battery compartment.

Lower Weight Battery

Essentially the battery just drops down in that little pocket and it fits perfectly but you will need to add a little bit of foam on the top so the battery door securely holds it in.  This recessed pocket is going to put the battery at its absolute lowest position in the rig. This battery is also not as heavy as that big stick pack, which is going to make a difference of eliminating weight up high and getting the weight as low as possible.

Traxxas 1400mAh Battery
Traxxas 2200mAh Battery

#2 - Adding Weights

Our next upgrade for the TRX-4 is not to remove weight but instead we're going to add weight to the low points on the axle.  STRC and Samix are two companies who are making some really nice-looking brass upgrades for the TRX-4.  The have portal covers, C hubs, hub carriers, shock link mounts, and spring perches, as well as, tons of different upgrades to add weight to the TRX4.  All of these pieces go on the axle at the very lowest point of the vehicle, which is a huge bonus for performance.

TRX4 Samix Portal

Doing the math; if you add up the Samix brass steering knuckle, C hubs, portal covers, and link mounts that right there is 12 ounces.  That's three-quarters of a pound you're adding to the TRX-4 and that's really going to make a difference.  Aside from being seriously good to look at, another big advantage of having these brass pieces is that most of them go on the front of the truck and that will also help offset the additional weight on the rear of the body. 

Samix Traxxas TRX-4 Brass Portal Knuckle Cover

Brass Portal Knuckle Cover

Samix Traxxas TRX-4 Brass Steering Knuckle

Brass Steering Knuckle

Samix Traxxas TRX-4 Brass Hub Carrier V2

Brass Hub Carrier V2

Samix Traxxas TRX-4 Brass Lower Shock/Link Mount Set

Brass Shock/Link Mount

#3 Reducing Body Weight

Speaking of bodies do you know what these things weigh out of the box?  This Defender body is 860 grams that's 1.9 pounds, the Tactical body is 594 which is about 1.3 pounds.  To give you a little perspective on body weight, we grabbed a SCX10 II scale body that was created by Matt, one of the talented employees here who makes some really awesome scale trucks. 

This particular body is a lexan Wrangler, I believe it's 4-door.  Matt has added tons of stuff to this body; we've got working lights, and looks like there's a radiator in there, there's a nice custom grille, we have our light bar, light pods, he added a roof rack that is stuffed to the gills, as well as more little accessories here on the back, more running lights. If we flip it over and look, inside there's also a light controller in there.  

Matt's awesome ride

This body has a lot of stuff on it, (tons and tons) of stuff, the weight… 818 grams, but it's still lighter than the Defender body!  So, with that said our really easy simple performance upgrade for the TRX-4 is to do something with the body.  If you're comfortable with it you can remove some of the accessories and the extra weight on the back of the body or even get a new body altogether, something that weighs significantly less.

Incision 313mm (12.3
Incision stock stainless-steel link kit

If changing the body is really an option for you, thanks to these Incision stainless-steel link kits you can do it fairly easily.  Incision has created a stainless-steel link kit that includes all the links you need to put the truck in a 313mm wheelbase, which is a very standard wheelbase for 1:10 crawlers of this class.  That opens up the possibility of being able to use any 313mm crawler bodies.

It's super nice to convert your truck to a more standard size and since these are stainless-steel, they are heavier than the included aluminum links on the bottom of the truck so that's going to add a more weight to the undercarriage which is always a performance boost.  There's also an Incision stainless steel link kit for the stock wheelbase if you just want to leave that where it is.

#4 - Adding Wheel Weight

The last simple upgrade we have is adding even more weight.  This time we're talking about adding weight inside the wheels.  The included wheels on the TRX-4 unfortunately are not beadlocks, they are glued to the tire so you will need new tires and wheels.  If you get beadlocks  like these Vanquish wheels there's a ring in the center, you can add sticky weight on that ring going all the way around, adding a lot of extra weight to each individual wheel, adding a lot of weight overall.  

Add Brass Weights to Lower Your CG

These just happened to be Vanquish beadlock wheels, they are very versatile wheels and they're metal, so they last a very long time and are a terrific investment in the long run.  They have a few advantages, they use the SLW hub beef tubes.  Beef Tube is a company that makes more brass weights for crawlers, and we've got a beef tube weight bolted up to this SLW hub here on the wheel.

Vanquish 1.9

Beadlock Wheels

ProTek RC Self Stick Chassis Weight Strip

Sticky Weights

Brass 1.9 SLW Beef Patties

Beef Tube SLW Patty Weights

Vanquish SLW Hubs

SLW Hubs

That's another big advantage to having this type of wheel you can add even more weight inside the hub, as well as, along the inside of the ring.  And if that wasn't good enough, another advantage to having the SLW hubs is they're adjustable!  You can buy them in different lengths to offset your wheel—basically from the axle.  When you add that extra width to your wheel, you're pushing out the tires further away from the axle and it's actually adding stability to the truck, especially when your site hilling or getting sideways.


The elimination of extra battery and body weight will help stabilize your TRX-4 but adding more weight down low is what's going to really make a difference.  The majority of the Samix parts listed here are added to the front for improved forward weight bias and performance. Keeping your kit forward balanced is going to help your crawler stay well planted and all this extra weight is going to help it stay tire side to the ground—and look pretty darn good too!  If this article has peaked your interest, be sure to check out our YouTube video below.

*Please note only Traxxas batteries should be used in TRX-4 kits.