~Chassis & Attachments~
Chassis
There are a few aftermarket chassis but they are typically designed to be raced. They are made out of stronger materials like aluminum for instance. I don't recommend these. If you are bashing, you want some amount of chassis flex. It will save you from a lot of other carnage. That is why I don't recommend a chassis brace either.
Traxxas LCG chassis($20)
gray / charcoal gray
However, If you have an HCG slash I highly recommend you get an LCG chassis. The HCG chassis offers no benefit over the LCG chassis except for being a slight bit stronger. The LCG chassis offers a lower CG and won't roll as easily, it has the same clearance as the HCG and won't get stuck when climbing. Although the HCG chassis seems like it has more clearance, it doesn't. The bulkheads are at the same height, and only the actual chassis is higher. This just makes it easier for you to get stuck.
LCG Conversion Kit($75)
If you have the HCG chassis, I recommend the LCG conversion kit. The conversion kit includes every part necessary to transfer from HCG to LCG. The conversion kit only comes with the gray chassis.
Nerf Bars
Nerf Bars are very helpful and make it easy to carry your truck, but they tend to rip.
RPM Nerf Bars($8.95)
Black / Blue
RPM makes a great nerf bars that come in multiple colors and are made with a reinforced compound that prevents breakage.
I personally don't like the way they look and don't use them too much. I prefer having them off. I think it gives a much cleaner look. If you don't like the indents in the chassis when they are off, you can also just cut off what sticks out from the chassis.
Battery Hold down
The stock battery hold down works pretty well but it is very limiting for battery size. If you want a longer run time there are a few options.
Xtreme Medium Double Strap
You can go with Velcro which will hold your battery/batteries well. With velcro, you can keep it lose so that the batteries fly out on impact, or tight so that they can't fly out. There are many different ways you can do this, and you could do this yourself. If you just want simplicity then the Pure-Tech Xtreme medium double strap is a very nice choice.
Traxxas Tall Battery Hold Down($6.50)
The Tall Battery Hold Down offers a lot of room for larger batteries and works for smaller batteries as well. There are two mounting points and often batteries are loose without foam.
Bumpers
Bumpers may be some of the most important pieces on your truck. They take a lot of the impact that could have gone directly to other parts. They protect your truck and are very visible so you want them to be effective and look good. For the most part, bumpers offer the same performance and its just visual.
RPM Bumpers
Front ($15.95) / Rear ($14.95)
The RPM bumper is a great choice. It comes in blue(Front / Rear), black(Front / Rear). You can also get it in a more expensive chrome on gray. Front ($17.95) / Rear ($16.95). The front bumper doesn't have a brace but comes with a full skid plate.
One of the main bonuses to this bumper is all of the accessories RPM offers.
Front Bumper Light Canister Set
Black($12.95) / Chrome($14.95)
These come without lights but lights can be added.
Tail Light Canister Set($9.95)
These also come without lights but lights can be added.
Apex Lights
Apex RC offers lights for all RPM "lighting" accessories
Front Bumper Lights($8.99)
These are for the RPM Front Bumper Light Canister Set
Rear Bumper Lights($6.99)
These are for the Tail Light Canister Set
Roof Rack Lights($9.99)
This is for RPM's roof light rack available in blue and black for $18.95 and in Chrome for $20.95. This isn't a bumper accessory, but they offer lights for it.
3 Male JST Servo extension Power Tap($4.99)
This power tap goes between a servo, and receiver providing 3 open JST plugs. This can be used to power Apex RC's Front Bumper Lights, Rear Bumper Lights, and Roof Rack Lights.
Single Tire Spare Tire Carrier($14.95)
Requires body modification. It fits one spare 2.2"/3.0" SC tire (not included). The tire lays on its side. You can only have one spare tire carrier. Either the Single or the Double.
Dual Tire Spare Tire Carrier($14.95)
Requires body modification. It fits two spare 2.2"/3.0" SC tires (not included). The tires stand upright. You can only have one spare tire carrier. Either the Single or the Double.
Low Visibility Wheelie Bar($9.95)
Doesn't work well with 2.8" wheels but is great for SC wheels. It is compatible with Traxxas' aluminum wheelie bar wheels(red / blue) which cost $19.99.
Mudflaps($10.95)
Just give a bit of protection from spraying rocks and add a nice touch of scale realism.
Traxxas Slash 2wd Wheelie Bar($15)
Black / Green / Blue / Pink
With a bit of modding, you could fit a more effective 2wd slash wheelie bar onto this bumper. This one would work better with larger 2.8" wheels. To mount this you will need to make a few screw holes. This is also compatible with Traxxas' aluminum wheelie bar wheels(red / blue) which cost $19.99.
T-Bone Racing
SCBasher Front Bumper($17.99)
This bumper has a clean look and a wide stance and comes with a front bumper brace.
XV4 Series Short Course Front Bumper($20.99)
The XV4 front bumper tries to capture a more scale look with the same durability. It also comes with a brace and has holes for mounting LEDs.
SC Racer Front Bumper($17.99)
This is a smaller bumper with larger air holes and is a good choice if you want something smaller.
SC Basher V3 Rear Bumper($18.99)
The SCBasher V3 rear bumper has air holes, a brace, and a skid plate and a clean look.
Of Course, there are many more great bumpers out there, these are just a few good ones.
Body Mounts
Body mounts are the secrets behind your truck looking so good. Without them, you would have no body which really takes the pop away. There are two main systems that you can use, each having their own pros and cons.
Pro-Line Extended Body Mounts($16.96)
These are the go-to mounts. They are very popular and for a good reason. They are great! They offer height customization. You could go as high or as low as you would like. They also come with a reinforcer to make sure they hold up when they are mounted higher. They use screw-on caps instead of body clips. You won't have to worry as much about losing body clips or ripping bodies anymore.
RPM body mounts($9.95)
These use a stronger plastic than stock and are an upgrade. However, they don't offer height customization. They actually are 1/8" lower than stock body mounts, but come with spacers to reach stock height. They use regular body clips.
RPM "No Clip" body mounts($27.95)
This is a kit that completely gets rid of body clips and offers a mounting system disguised as scale realism. They have a great tutorial here. This is very cool but has only been tested on certain stock bodies, and there is no guarantee this will fit on an aftermarket body. You can read about the limitations here. Scroll down in the description until you see "Tech Notes".