View Full Version : How many bearings and what size in a 03?

2011.03.09, 08:44 PM
I'm trying to buy bearings from Reflex Racing but their 'kit' is out of stock. So I want to peice together a kit from they're website.

I'm a little confused on the quantity in the rear. 2 in the mount and how many in the diff area, 1 or 2? I know the spur goes around one, and the wheel goes around one too, is the wheel going around the same bearing the spur went over? my car isn't accessible to reference at the moment

if you know the sizes that would be awesome too. thanks

2011.03.09, 09:01 PM
4x 2x6x2.5 for front wheels
3x 3x6x2.5 for diff axle. Two in mount, one on outside of right wheel. Left wheel is fixed to shaft, so it uses a bushing rather than a bearing. Diff should already have a 3x6x2.5 included.

I usually try to have a few 3x6x2mm bearings just incase a wheel tightens up the diff action. This is the standard size for the AWD axle bearings. .5mm narrower than the 2wd rear axle bearings.

2011.03.09, 09:09 PM

So what are the 4x7's for on the reflex site?


2011.03.09, 09:11 PM
it is for the spur gear

2011.03.09, 09:13 PM
Thanks Chad, but EMU mentions below the Diff takes the 3x6x2.5

you think otherwise? I don't want to waste money on these things. thanks

2011.03.09, 09:15 PM
the 4x7 goes on the spur gear. the ones emu gave you is what comes in the bearing kits. if you get a ball diff it will come with the 4x7

2011.03.09, 09:18 PM
The diff when built has 2 bearings in it if you use a 64p spur. One in the center of the spur (4x7), and one for the tention bearing (3x6x2.5). Hope the info helps...

2011.03.09, 09:22 PM
yes it helps thanks, I guess I don't have that diff. so the kit comes with 7 bearings total, (4) 3x6x2.5 and (3) 2x6x2.5

If that's correct, this thread is closed. thanks guys

2011.03.09, 09:33 PM
If you're rich and cost is no object you can stick one 6x2x2.5mm and one 6x3x2.5mm bearing in the left side wheel. Because the left wheel turns with the shaft they serve no purpose as bearings but they have tighter tolerances than the plastic bushings. This will keep the left side wheel from developing any slop (not applicable to gear diffs unless they've been upgraded with a spline nut that has a set screw).

Slop in the left rear wheel can cause handling problems if it gets severe. The plastic bushings usually deform over time and won't be able to sustain a slop-free fit no matter how much you tighten the nut.

If you're not using a very hot motor it might never be a problem, but as power and speed increase any slightly loose nut on the wheels or loose screw on the motor mount or a misaligned t-plate can cause serious problems.

2011.03.09, 09:36 PM
interesting, they're not options though! for the $1.99 I would have done it!