People on here were saying centro is the AE European division, not a imitation. If the chassis hauls the mail like never before from what I'm seeing and reading then how is that a band aid? I'm buying one. Tomorrow hopefully!

Agreed. The more time you spend breaking the diff in, the longer it will last. When I'm not impatient, the diff will last almost as long as the outdrives.

If I'm being REALLY bad, and just want a quick fix for the day, then I'll pull out just the thrust assembly, and clean/replace. It'll make the diff much smoother.

When it comes to Diffs, you either build them properly or you don't, and with experience you get better at it. The biggest mistake I find people make is that they don't tighten their thrust down enough and therefore they get the bark which is vibration. If it can vibrate, things aren't torqued enough and some balls will have a bit more pressure on them and thus wear more quickly and unevenly than the rest and it's downhill from there. For my break-in I simply hold one wheel and throttle it lightly for about 30 seconds and then do the other side, then switch sides again and feather it a few times, then gun it for a bit, then do the same on the other side and it's done.

When the diff is built properly it can be felt immediately, and if it's wrong it's quite apparent as well. All I do is make sure my rings are indeed flat and I make sure they're free from ALL debris (even fine fibers can make for a rough diff) and use the proper lubes. My Diffs are ultra-smooth and they last forever that way and I only redo them if I have to tear down my Tranny for some reason. I've only ever had 2 diffs feel gritty and that was due to debris getting in. My current Diff has 6 months on it so it will be getting changed soon.

I just recently upgraded to the Avid Thrust bearings which are all enclosed. I cant wait to try it out this weekend.

Do that last longer than regular?

Those are encase, not enclosed. The balls reside on a disc washer so no more fumbling around with individual balls. Just slide the Avid ball assembly on and tighten down as you normally would. I'd venture to say the added bonus is the washer traps grease on the backside so the balls constantly pick up grease to remain lubed.

I would think the grooved washers are nice to help keep lube in also. I plan to try them on my next rebuild. I "THINK" the kits thrust balls are steel and not carbide. It does not seem to say anywhere, but based on the price of them, I am making that assumption. If I get the avid, I am torn between the ceramics and the tunston

Ceramic thrust Ball and Tungsten Diff Ball... all day everyday.

yeah, that is what I am thinking.

Well im not sure what kind of carpet you have outdoor and i gaurentee since its outdoor it doesnt have as much traction as the indoor track i run at, rear motor and the rear motor cars have beaten up on the mid motor cars atm, the one guy is right with us but he is a sponsored driver bet he'd go faster with one of our cars rear motor im with u guys on the new car the b4.3 or b5 would be cool

MM typically would shine more in a mod class than stock. I don't know if you have ever felt an XFactory or Centro car for that matter, but they are not light.... at all.

Diff tips

No drill or sanding needed..


As you tighten down use less then 1 or 2 turns of the screw and roll the gear to break in the groove on the rings . As you tighten fewer turns and keep rolling gear to help push the balls into the ring to form the groove the balls ride inside .

When you reached bottom and think the diff is tight ?

use two drivers between the cups and torque the gear by hand .
If it the gear slips continue to tighten and roll the gear until you cannot move the gear by hand.

next
Install the gear into transmission ...

Switch car on and grip one wheel .
Give the car a small amount of throttle to spin the tire .

You don't need full speed , just part throttle is plenty .
After spinning each rear tire for a minute or two check the diff tightness.

It should of free up a bit and will need to be tighten some more.

tighten diff screw once again
then

break it in some more & check if the diff has not free up again .

if no change in the tightness ?

You are done ... enjoy

What ball cups are people using? I've gone through several stock ones and I'm wondering which ones I should upgrade to. Preferably black ones as I don't really like the look of colored ones.

The RPM ones are decent. Have you tried the new AE low friction cups? I think they are greyish though. But they are getting good reviews.

RPM here.