SC10 gear diff issues

[Hog]

Having trashed yet another gear diff last night in my SC10 whilst running on a polished wooden surface, it's apparent that I must be doing something wrong whilst building them.

The slipper is set right - so I assume it must be to do with the shimming of the internal gears? Any tips to make it last longer?

It's funny - the SC10 comes with a gear diff, and my Centro 4.2 a ball diff, and now I'm looking at doing away with the aggro of the gear diff in the SC10 and replacing it with a ball diff, and swapping the Centro ball diff to a gear diff to get more drive!

Or is the gear diff simply not really "man" enough for the truck?

[Big G]

I never damaged mine when I ran the SC10 on carpet over jumps. What's breaking in them?

[Hog]

Not breaking as such - just making some real nasty clicking noises under acceleration and turning. As though the mesh isn't tight enough and the gears are jumping? Got worse as the night progressed last night.

I had issues a while back with the thickness of the shims supplied - I trashed a brand new diff in one race on grass as the supplied shims were too thin and let the gears jump.

I'm tempted to bin the gear diff in the SC10 and just go for a ball diff - but there must be a reason for it?

[jon kedge]

Hi there,i had this problem with mine and the fix is to double up on the thin steel shims,2 each side pushing against the gears ,it works as i run a 6000kv sensorless in mine and ran it for 1year at coventry ,kiddy and other club meetings in the mid west,now run it as a staduim truck with no problems with 5000 wt oil.hope this helps it did me....

[Hog]

Thanks Jon. It does appear there are 2 types of rebuild kit. One seems to have 2 thick shims and 4 small for the smaller gears inside. The other just has 4 thin shims for the main gears.

I have just dropped a gear diff in my Centro with doubled up shims so hopefully that will hold. I'll rebuild the truck diff the same and see what happens.

[Hog]

Right - a quick update on this.

Rebuild kit for my damaged gear diff arrived - the kit had 2 large shims and 4 small for the internal gears. Built it up exactly as per the instructions and it's cack - notchy and really not nice at all. I tried to squeeze another really thin shim in on the outdrive gear but there just wasn't room to get the drive pin in as well. I've now got 2 gear diffs installed in the Centro and SC10 that I don't 100% trust, and a spare in the box that feels like it will make a good paperweight

So I think it's time to throw in the towel and revert to ball diffs in the truck and Centro. I have enough B4 diffs laying around but obviously the B4 was Imperial and everything since went Metric.

Can I get away with just buying new SC10/B4.1 outdrives for the B4 diffs rather than buying complete new diffs? Will the drive rings and thriust race be a straight swap? I know I need the Metric outdrives as the SC10 and Centro use the 10x16mm bearings.

Thanks for any advice!

[MHeadling]

Hi Hog, To go to the B4.1/2 diff you'll just need the updated metric out drives and metric bearings, all the other diff parts are the same

I used the MIP B4.1 out drives, cheaper than AE ones and they seem to wear less

I got my ones from Les at Xtreme rc, give him a shout

[mattr]

Just an idea, my diff issues have all (ok, mostly) been caused by the casings, rather than the actual diff.
Either a small crack that opens up under load allowing pins to move and gears to come out of mesh, or poor tolerancing........

Have you checked or swapped the diff housings?

[Hog]

Thanks Mark - just what I wanted to hear.

Matt - casings are always cleaned and inspected before a rebuild. If the casing is damaged (or as it was in one instance - melted) then it gets replaced in its entirety.

Ball diffs it is then

[Adam Talbot]

hi hog,are you running grease or oil in your diffs?

[Hog]

Oil Adam. But I've assembled the diffs dry as well to offer everything up and the mesh is rubbish.

[Hog]

Quick question - has anyone tried the Hot Racing alloy diff casing for the SC10?