Start with the problem you want to fix: consider GTR shocks for suspension tuning, a compatible aluminum slipper-bearing adapter during driveline service, or the 7421 low-CG conversion for a standard-chassis truck used on smoother courses. None is a required purchase for every Slash 4×4. An Ultimate may already have the suspension and chassis equipment you are shopping for.
This guide covers the 1/10-scale Slash 4×4. Do not apply these part numbers to a Slash 2WD, 1/16 Slash, Mini Slash, or Maxx Slash just because the name is similar.
Research disclosure: We reviewed Traxxas product information, parts lists, and manuals on October 4, 2026. We have not track-tested these upgrades or measured durability gains. Recommendations are conditional on your exact model and existing parts.
Three upgrades to compare
| Candidate | Reason to consider it | Main limitation |
|---|---|---|
| GTR shocks: 7461X and 7462X | Serviceable aluminum shocks with threaded preload adjustment | Different front/rear lengths; springs are separate |
| 6893X aluminum bearing adapter | Replacing a compatible slipper-shaft adapter while servicing the driveline | Check the installed center-drive assembly; inspect the bearing too |
| 7421 low-CG chassis conversion | A chassis-layout change for a compatible standard-chassis 4×4 | More involved work; little reason to buy it for an existing LCG truck |
1. GTR shocks: a useful tuning upgrade
Traxxas lists 7461X long GTR shocks with hard-anodized aluminum bodies, PTFE coating, titanium-nitride-coated shafts, and threaded spring collars. The package is a pair, and springs are sold separately.
The Slash 4×4 BL-2s parts list also identifies 7462X XX-long GTR shocks and the separate long and XX-long spring families. Have your shop confirm the front long/rear XX-long combination and spring selection against your truck’s parts diagram. Four identical shocks or a four-pack of identical springs is not a safe ordering shortcut.
Why buy: This is worth considering when you want a rebuildable shock package and easier preload adjustment. Traxxas’ shock-tuning guide explains how ride height, springs, and damping affect setup. Start from a documented baseline and change one setting at a time.
Why wait: A leaking seal, bent shaft, or incorrect setup may call for repair rather than four new shocks. The 68077-4 Ultimate manual already describes GTR shocks and a low-CG chassis. Inspect your own Ultimate before ordering replacements marketed as upgrades.
2. Aluminum slipper-bearing adapter: check the assembly first
The 68386-4 Slash 4×4 VXL parts list identifies 6893X as a blue-anodized 6061-T6 aluminum adapter with a 10 × 15 × 4 mm bearing for the slipper shaft.
Why buy: It is a focused part to investigate when a compatible truck is apart for slipper or bearing service. Check whether the existing adapter is already aluminum, then compare the replacement with the exploded view rather than ordering from a generic “Slash upgrade” bundle.
Limits: The adapter is associated with the slipper assembly. If a previous owner fitted a center differential or another center-drive conversion, identify that system first. An aluminum adapter does not cure a seized bearing, incorrect clutch adjustment, or poor gear mesh. Diagnose those issues instead of expecting the material change to make the truck maintenance-free.
3. Low-CG conversion: choose it for a particular use
Traxxas documents the 7421 low-CG chassis conversion kit in both the BL-2s and VXL parts lists linked above. This is a chassis conversion for the applicable 1/10 Slash 4×4, so allow time for disassembly, inspection, and careful reassembly.
Why buy: Consider it if a lower chassis layout suits the smoother track or paved course you actually use. Traxxas’ suspension guidance links lower ride-height setups with smooth, high-grip conditions and higher settings with rougher terrain. That makes terrain a better deciding factor than the number of upgrades already fitted.
Limits: Confirm body mounts, battery retention, receiver-box mounting, and any existing brace against the conversion instructions. Clipless-body revisions and aftermarket parts deserve an explicit compatibility check. If the truck already has an LCG chassis, spend the budget on wear items or setup instead.
Check these details before buying
- Exact model number: Use the box, manual, or vehicle records. Examples include BL-2s 68154-4, VXL 68386-4, and Ultimate variants; the name on the body is insufficient.
- Actual generation and equipment: Identify standard or low-CG chassis, clipless or body-clip mounting, and standard or Extreme Heavy Duty suspension/driveline parts.
- Used-truck changes: Photograph the installed shocks, axles, hubs, slipper or center differential, motor, and electronic speed control for the supplier.
- Complete installed cost: Include springs, oil, required hardware, and tools. Compare like-for-like pairs and complete kits.
- Driving complaint: Note whether the problem is rolling in corners, inconsistent landings, binding, or repeated damage in a particular area. Change one thing, then reassess.
Keep the power system within its limits
The BL-2s manual specifies 6–7-cell NiMH or 2S LiPo power. A 3S LiPo is not an appropriate upgrade for that ESC. For a VXL-equipped truck, use the exact ESC and vehicle manuals to verify the battery, gearing, and operating conditions; “Slash 4×4” alone does not establish compatibility.
Keep LiPo low-voltage protection enabled and follow the battery and charger instructions. Do not disable protective cutoffs or treat a cooling fan as permission to use unsupported batteries or gearing.
Frequently asked questions
Should I replace every plastic part with aluminum?
No. Buy a documented part for a specific need. A complete metal-parts bundle can create fitment questions without addressing the problem that prompted the purchase.
Will these upgrades make a BL-2s truck 3S-compatible?
No. Suspension and chassis changes do not change the ESC’s permitted battery voltage.
What should an Ultimate owner upgrade first?
First inventory the equipment already installed and inspect wear items. GTR shocks or an LCG conversion may duplicate what the truck already has. Let the driving problem and exact parts list guide the next purchase.
Image note: Generic editorial illustration of a short-course RC truck; this is not a Traxxas product photo and does not establish upgrade compatibility.
