X-Maxx & XRT Upgrade Guide

The X-Maxx and XRT are two of the toughest trucks Traxxas builds, and they share most of their parts, so they share most of their upgrades too. This guide covers both. It starts with the upgrades we recommend to every owner, then moves to the bigger drivetrain and chassis upgrades for trucks that see hard use. Where a part is different between the two trucks, we list the X-Maxx and XRT versions separately. Some fixes are parts we design and print in our Wisconsin shop, some are GPM Racing metal parts we stock as an authorized reseller, and some are parts we don't sell. We say which is which.

Written by the team at 3D Abilities in Wisconsin. We've been designing since 2014 and running our own RC trucks since 2020, and the advice here comes from our own builds and thousands of customer orders and questions.

Traxxas XRT upgraded with 3D Abilities partsCustomer Traxxas X-Maxx build with custom body and 3D Abilities parts

Quick answer: where to start

For a new or mostly stock X-Maxx or XRT, start with these four:

  1. Steering: a stronger servo and a metal servo mount and horn. Stock steering is the most common complaint.
  2. Suspension pins: carbon steel pins that don't bend on hard landings.
  3. Battery mounts: hold downs that keep the packs in place, and fit bigger packs.
  4. Cooling: fans on the motor. Heat quietly shortens the life of the motor and ESC.

Add body protection and mud and chassis guards as you bash more. Once you're running harder, move on to the drivetrain, gears and bulkheads.

Start here

1. Steering

What fails: Both trucks are heavy, and the stock servo has to turn big tires under load. Owners report servos that overheat or seize, plastic servo horns that strip, and slop in the linkage that gets worse every run.

The fix: Start with a high torque, metal gear servo. We don't sell servos. Our pick is the PerfectPass 56kg servo (Amazon affiliate link), mounted with the GPM Servo Horn Set below, which fits both trucks. Then replace the parts between the servo and the wheels:

2. Suspension pins, shocks and rear hubs

What fails: Suspension pins bend, A-arms and rear axle carriers break on hard landings, and shock caps pop or leak. Dirt on the shock shafts wears out the seals.

The fix: Start with steel pins, which are one of the cheapest upgrades on either truck. For arms, stick with Traxxas HD (heavy duty) arms. We don't sell arms, and they're the right part for the job.

If you bash hard, skip aluminum rear hubs and aluminum suspension links. Aluminum doesn't flex, so on a hard landing it bends or passes the hit into the arms and bulkheads, and a bent hub or link is a replacement, not a repair. Stock or heavy duty composite parts flex and come back. Aluminum carriers make more sense for speed runs and track driving, where stiffness matters more than surviving cartwheels.

3. Battery mounts

What fails: Hard landings and rollovers test the stock battery hold downs, and bigger aftermarket packs often don't fit them at all. A pack that shifts or comes loose can damage the wiring and the pack itself.

The fix: Two ways to do it:

4. Cooling

What fails: Heat, and the stock fans themselves. Long runs, 8S, tall gearing and hot days push the motor and ESC hard, and stock fan blades get smashed by debris and chassis slap. Heat won't break anything in one run. It shortens the life of the motor and ESC over many.

The fix: Put good fans on the motor and keep them in the airflow. This is the one section where the two trucks need different parts.

Every shroud can be ordered with Rocket RC fans. Running an aftermarket motor? Shop shrouds by motor size.

How much does it help? One X-Maxx 8S owner on RCTalk swapped his worn stock fans for Rocket fans and reported his motor running mostly at 110 to 125°F, down from 150 to 165°F before the swap. Your results will depend on motor, gearing and weather.

5. Body protection, mud and chassis guards

What fails: Mud, rocks and grass get into the chassis and electronics, the skid plates get chewed up, and the body takes a beating on every rollover. Most of this is wear, not a single break, which is why it's easy to ignore until something stops working.

The fix: This is our specialty. Printed protection flexes on impact where hard parts crack or pass the hit into the chassis.

Once you're running harder

6. Drivetrain and gears

What fails: On 6S, and much faster on 8S, the drivetrain takes the abuse. The usual list: stripped spur and pinion gears, worn diff gears, worn cush drive dampers, and dogbones or CVDs that wear or pop out on big landings.

The fix:

Make them last: after any drivetrain upgrade, keep the diffs topped up with fluid and check your gear mesh. Low diff fluid wears out diff gears fast, and a mesh that's too loose strips teeth while one that's too tight wears them out. Five minutes of checking protects the parts you just bought.

7. Chassis and bulkheads

What fails: On heavily bashed trucks, especially on 8S, the bulkheads and tie bars take the hits that get past the bumpers. A failed diff can also chew up the bulkhead around it.

The fix: These are bigger upgrades for trucks that see hard use.

8. ESC and electronics

What fails: The stock ESC is fine for stock power, but owners who add a bigger motor or run hard on 8S often outgrow it. Most owners replace it with a Hobbywing Max6 G2, or step up to the Max5 series for an upgraded power system. (The Max8 is built for 1/8 scale trucks.) The problem then becomes where to mount it.

The fix: We don't sell ESCs, but we make the mounts that put an aftermarket ESC where it belongs:

9. Wheels and tires

What fails: Stock tires balloon at speed and can tear, wheel nuts back off, and hex hubs wear.

The fix: We don't sell tires. Belted tires stop ballooning. For the rest:

Upgrades won't help if the screws back out

Metal to metal screws loosen from vibration. Put threadlocker on anything that takes impact: bumpers, motor mounts, skid plates and aluminum parts. See the threadlocker, diff fluid and shock oil we use on our Recommended Gear page.

Common questions

What should I upgrade first on an X-Maxx or XRT?

Steering, suspension pins, battery mounts and motor cooling. Add body protection and mud and chassis guards as you bash more. Save the drivetrain, gears and bulkheads for when you're running harder or on 8S.

What breaks first on a Traxxas X-Maxx or XRT?

For most owners it's the steering, then the drivetrain: stripped gears, worn cush drive dampers and diffs that ran low on fluid. Heat is the slow killer behind both the motor and the ESC.

Which parts are different between the X-Maxx and XRT?

Most drivetrain, suspension pin, shock and bulkhead parts are shared. The parts that differ are the ones tied to each truck's body and layout: motor shrouds, fender flares, mudguards, bumper mounts, gear covers, dogbones (160mm on the X-Maxx, 190mm on the XRT), center driveshafts, chassis plates, steering assemblies and battery hold downs. Check the compatibility list on each product. We only list a truck when the part is confirmed to fit it.

Which motor fan shroud fits my truck?

On the X-Maxx, use one of our chassis brace shrouds (2x40mm or 4x40mm). They fit the stock brace and the M2C brace plate. On the XRT, use our 56mm shrouds (2x40mm low profile or 4x40mm). The 56mm low profile shroud does not fit the X-Maxx, because the chassis brace is in the way.

What gearing should I run?

It depends on your motor, battery and tires. Start with Traxxas' recommended gearing for your setup, run for five minutes, and check motor temperature. If it's too hot to hold your finger on, gear down.

Will a Mod 1.5 pinion work with my stock spur gear?

No. Mod 1.0 and Mod 1.5 gears have different tooth sizes and won't mesh. The stock X-Maxx and XRT use Mod 1.0 gears. To switch to Mod 1.5 you replace the pinion and spur together, which is why we sell Mod 1.5 as matched sets. Check the bore size on the pinion too, so it matches your motor shaft.

Does the GPM 12T/33T Mod 1.5 gear set keep the stock cush drive?

No. It replaces the stock cush drive assembly. The 33T spur mounts to the included shaft with a set screw. Check the Package Includes section on each gear listing before you order.

Do your parts fit the X-Monster or other X-Maxx versions?

Most X-Maxx parts fit the 6S, 8S and Ultimate versions, but Traxxas changed a few parts on newer trucks. For example, our lower bumper mounts don't fit the X-Monster. Check the compatibility list on each product, and message us with your model number if you're unsure.

Do the mudguards fit under the stock body?

Yes. They're designed around each truck's stock body and clamp onto the chassis with no drilling. Some aftermarket bodies may need light trimming, so check the photos on each listing.

Do the X-Maxx fender flares come with hardware?

Yes. Our X-Maxx fender flares include 48 M3x12 screws and 48 M3 locknuts, enough for all four flares.

Which battery mounts should I use for big 6S packs?

Our hold down mounts for the X-Maxx and XRT fit larger packs on the stock tray with no chassis modification, and come with two 600x20mm Kevlar straps. If you'd rather replace the tray entirely, our 4mm carbon fiber tray fits both trucks and has its own three strap system, so you don't need the hold downs with it.

Is aluminum or 3D printed better?

It depends on the job. Aluminum and steel belong where a part has to stay rigid or resist wear: steering, bulkheads, gears and drivetrain. Printed parts are better for protection, like mudguards, bumper mounts and body savers, because they flex on impact and take the hit instead of passing it into the chassis. If you bash hard, keep the rear hubs and suspension links stock or heavy duty composite too. Aluminum there tends to bend instead of flex. We carry both.

Do I need every upgrade on this list?

No. Start with the four in the quick answer and add the rest as parts wear or break. A truck run on 8S, or jumped hard, will need the drivetrain and chassis upgrades sooner.

Everything on this page ships from Wisconsin. Orders placed by 1pm CT, Monday to Friday, ship the same business day. See every part we carry for the X-Maxx and the XRT.

As an Amazon Associate, 3D Abilities earns from qualifying purchases made through affiliate links on this page.

Last updated: October 2026

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