How-To: Slash 4×4 MT Conversion

The Slash 4×4 is an amazingly versatile vehicle. It can be a bulletproof backyard basher, a multi-surface rally car, a corner carving racer, or, with a little creativity, a high-riding monster. Traxxas themselves created a short-wheelbase monster using the Slash 4×4’s architecture and it is a really fun little bundle of wheelie popping joy. But what if they had used the Slash 4×4 to create a lighter, more athletic MT to compete with the likes of the E-Maxx, E-Revo, or others? The world may never know, as Traxxas would be creating a truck that would hurt their own sales figures of the more established “classic” trucks. With the addition of a few parts and the removal of few others though you can create your own 4×4 lightweight monster that still flies the TRX flag proudly. Here’s how.

Step One: Remove the bumpers and nerf bars

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I used a cut down Slash 4×4 bumper to retain the hinge pins without sacrificing the look I was going for.

Step Two: Add MT wheels and tires (and hex adapters if necessary)

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I am using Pro-line’s Masher 2.8″ tires stretched over RPM’s 3.2″ Revolver “Stablemaxx” offset wheels. I love these tires and they have served me well for quite a while (I’ve had at least one set since 2013). I like the look of the larger wheels and they give the tires a lower profile look. The adapters are from AKA, but I also use a set of splined 17mm adapters from Hot Racing from time to time. The wrench that I have for the splined adapters has a longer reach and can be used with the high offset wheels, whereas a standard 4-way 17mm wrench can’t reach the wheel nut. I have also used RPM’s Revolver 2.2″ wide offset crawler wheels and Pro-line’s 2.2″ BFGoodrich KO2 tires. These look a little more scale and are taller than the Mashers. The RPM wheel is also the only 2.2″ wheel that will fit on the Slash 4×4 without rubbing.

Step Three: Body mounts

I am using Pro-line’s extended body mounts for the Traxxas Slash 4×4 and Stampede 4×4. I have modified mine with Rustler battery hold down posts as I lost the screw on caps that came with the PL mounts.

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Step Four: Add a Monster shell

I chose the Pro-line Jeep Rubicon designed for the T-Maxx 3.3 and Revo 3.3 (item #3405-00). This body has the correct wheelbase and width for the Slash chassis. If I choose to run the Mashers on this truck long term I will be trimming the flares and replacing them with a set of higher arched flat style flares. The stock flares do rub the tires a little but this could be solved with wider hexes or some Dremel work on the flares themselves.

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I also added a Stamped 4×4 wheelie bar to help protect the rear of the Jeep body and also keep the rear hinge pins in place. This is a direct bolt on and is a must with the larger tires.

Step Five: Gearing

I replaced the 17t pinion in my truck with a 13t to keep the temps in check and regain some torque. The motor and ESC both run cool after a full pack and the truck has enough power to pull the front end up at any speed below 3/4 throttle.


This truck is very impressive. It handles so much better than an E-Maxx, is more durable, and is faster to boot. I ran this truck back to back with my 3906 E-Maxx and it was a night and day difference. I didn’t have to walk over and flip the truck back onto its wheels nearly as much as the Maxx. The truck steers with more authority and precision than the pillow ball equipped Maxx. The lighter Slash MT jumps and lands like a dream compared to the Maxx which lands with a thud and loses most of its forward drive when trying to regain its composure. The larger MT tires allow the Slash to roll over rough terrain much better than the stock 2.2/3.0″ tires do. The Slash MT is also much more stable than a Stampede 4×4 and is easier to drive at high speeds. The Stampede likes to list from side to side as the tires grow at different rates and this is amplified by the trucks short wheelbase. The Slash tracks straighter, even while on the wheelie bar, and is easier to drive at the limit.

Overall there is no reason not to convert your Slash into a monster truck if you are shopping for a 1/10 MT. The Slash is just as capable as an E-Maxx in 90% of driving situations, is more durable, and also only requires one battery. Plus when that battery is dead, the truck is much easier to carry back to the workbench than its portlier sibling.

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Click the image to open in full size.
Click the image to open in full size.
Click the image to open in full size.

Parts List:
RPM Stablemaxx Wheels:…x-offset-17mm/
Pro-line Jeep Rubicon:…clear-body-mt/
Pro-line Masher 2.8:…n-truck-tires/
Pro-line Extended Body mounts:…nts-slash-4×4/

A special thanks goes out to the great folks at Pro-line Racing and RPM RC Products without whom this would not have been possible. __________________