Which RC Brands Use Common Bearing Sizes?

A gritty wheel bearing or notchy drivetrain does not always mean you need a brand-specific part. Many hobby-grade platforms share standard metric bearing dimensions, which is why the question which RC brands use common bearing sizes is useful when planning a rebuild. The catch is that a shared size in one part of the vehicle does not guarantee the whole bearing set is interchangeable.

Traxxas, ARRMA, Losi, Team Associated, Axial, HPI, FTX, HoBao and Kyosho all use standard-sized bearings across much of their range. That makes sourcing straightforward when you know the inner diameter, outer diameter and width. It also makes exact model fitment worth checking before ordering, particularly on older platforms, revised versions and vehicles with optional hubs or transmission parts.

Why common bearing sizes matter

RC manufacturers generally build around readily available metric bearing sizes rather than creating a unique bearing for every model. Sizes such as 3x6x2.5mm, 4x8x3mm, 5x10x4mm, 5x11x4mm, 6x12x4mm, 8x16x5mm and 10x15x4mm appear repeatedly in wheel hubs, gearboxes, differentials, steering assemblies and clutch systems.

That is good news for maintenance. Once you have measured a removed bearing or confirmed the original specification, you can replace it with a quality bearing of the same dimensions without being tied to a branded packet. Better bearings can improve free-running transmission movement, reduce play caused by worn races and give a rebuilt vehicle a more consistent feel.

The practical distinction is between a common bearing size and a common bearing kit. A 5x10x4mm bearing may fit countless RC cars, but the number of that size required and its position in the vehicle vary widely. Two vehicles from the same manufacturer can have completely different kits.

Which RC brands use common bearing sizes most often?

Traxxas

Traxxas vehicles use many familiar metric sizes, particularly through the wheel hubs and driveline. Models in the Slash, Rustler, Stampede, Bandit, Revo, Maxx and X-Maxx families often include sizes that are easy to source individually. The 5x11x4mm and 6x12x4mm formats are particularly familiar to Traxxas owners, although the precise mix changes between 2WD, 4WD and larger-scale models.

Do not assume bearings transfer between versions simply because the model name is similar. A Slash 2WD and Slash 4x4, for example, share a name and some components but have very different transmission and hub arrangements.

ARRMA

ARRMA is another brand with strong use of standard metric bearings. The 3S, 4S, 6S and 8S ranges use recurring dimensions across hubs, diffs and centre driveline assemblies, especially within related chassis families. This can make it economical to keep a few commonly used sizes in the workshop if you run several ARRMA vehicles.

However, ARRMA platform revisions matter. V3, V4, V5, EXB and later releases may use revised hubs, differentials or motor mounts. Check the exact vehicle designation rather than relying on an earlier kit listing.

Losi and Team Associated

Losi and Team Associated race-bred buggies, stadium lorries and short-course vehicles commonly use standard sizes, but their bearing layouts can be more model-specific than those of a basic basher. Fine-pitch transmission layouts, compact steering assemblies and competition-focused hubs can introduce smaller or thinner bearings alongside the usual wheel-bearing sizes.

This is where fitment-led buying saves time. A bearing may have the correct inside and outside diameter but still be too wide for a gearbox case or hub carrier. Width is not a minor detail - it controls whether the bearing seats correctly and whether the assembly has unwanted side load.

Axial and other crawler brands

Axial crawler platforms make extensive use of standard metric bearings, with 5x11x4mm, 5x10x4mm, 6x12x4mm and 10x15x4mm among the sizes frequently encountered across axles, transmissions and portals. SCX10, Capra, Wraith and RBX-based models may share individual sizes, but axle generation and transmission choice affect the full list.

Crawlers deserve slightly different bearing consideration. Water, mud and fine grit place a heavy load on axle and wheel bearings, so a seal that suits your conditions matters as much as the dimensions. Rubber-sealed bearings are generally the sensible choice for vehicles that see wet trails and repeated cleaning. Metal-shielded bearings can offer low rolling resistance in cleaner, drier applications, but they are less suited to sustained contamination.

HPI, FTX, HoBao and Kyosho

HPI, FTX, HoBao and Kyosho also rely heavily on industry-standard metric sizes. HPI Savage, Sprint and Baja-era platforms, HoBao nitro and electric buggies, FTX bashers and crawlers, and many Kyosho kits all contain bearings that can be identified and replaced by size.

These brands demonstrate why model-specific checking still matters. Older HPI and Kyosho vehicles can have several production revisions, while FTX often has different arrangements between entry-level models and upgraded versions. Nitro models add another variable: clutch bearings, bell bearings and crankshaft support locations may require particular sizes and may experience more heat than a typical electric drivetrain bearing.

The sizes you are most likely to encounter

For many 1/10-scale cars and lorries, 5x10x4mm, 5x11x4mm and 6x12x4mm are among the most useful sizes to recognise. They are common in wheel hubs, gearboxes and differentials across several brands. Smaller 3x6x2.5mm and 4x8x3mm bearings appear in steering bellcranks, compact gearboxes and smaller vehicles, while 8x16x5mm and 10x15x4mm are familiar in larger hubs, centre driveline locations and bigger-scale platforms.

That does not make these universal sizes. A 1/8 buggy, for instance, may use 8x16x5mm wheel bearings where a 1/10 buggy uses 5x10x4mm. A monster lorry can use larger hub bearings yet retain smaller bearings in its transmission. Build a list from your actual vehicle rather than ordering a general assortment and hoping it covers the job.

Measure the bearing, then confirm the fitment

The bearing code follows a simple format: inner diameter x outer diameter x width, all in millimetres. A 5x10x4mm bearing has a 5mm bore, 10mm outside diameter and 4mm width. Digital callipers are the quickest way to verify a removed part, especially when markings are worn or missing.

Measure a clean bearing rather than one still pressed into a carrier. Check all three dimensions, then compare it with the vehicle's parts diagram or a model-specific bearing kit listing. If a bearing is badly corroded, crushed or loose in the housing, measure the replacement location carefully as well. Damage can make an old bearing misleading.

Also identify the position before choosing the bearing type. Wheel bearings live with dirt and side loads. Gearbox bearings usually prioritise smooth rotation and protection from dust. Engine-adjacent bearings may see heat, fuel residue or higher rpm. The same dimensions can be correct, while the best seal and grade for the position differ.

Common sizes are useful, but exact kits are faster

Buying by size is ideal when replacing one failed hub bearing, refreshing a differential or keeping spares ready for a race meeting. It is also useful where a previous owner has fitted non-standard upgrades and you need to identify the part in front of you.

A vehicle-specific kit is usually the better route for a full rebuild. It accounts for quantities, different widths and the small bearings that are easy to overlook in a transmission or steering assembly. At 888-RC, the choice between shopping by measurement and by model exists for exactly this reason: use the route that gives you confidence in the part you are replacing.

Common bearing sizes make RC maintenance less complicated, but they do not remove the need for accuracy. Confirm the dimensions, confirm the vehicle version, and fit a bearing suited to where it works. Your drivetrain will be smoother for it, and you will avoid turning a simple repair into a second strip-down.