Hello,
First can I say that I am a complete novice at car/truck building and this is my first ever build. The kit is the M1035 Hummer. I would like some advice on locking the diffs and if both should be locked. It will be mostly run off road.

Can I first start by asking, if I was to lock the rear diff, do I epoxy everything between pressure plate A (AB3) and pressure plate B (AB2) on the rear diff spur gear. Then from the other side of the spur gear, epoxy everything that is screwed down into AB3 underneath the pressure plate cap?

Next, If I was to lock the front diff, would I simply epoxy all the parts underneath the front diff spur gear diff cover?

I have read that some people put the rear Ball diff in the front. (Would you leave this diff unlocked ) They then lock the front Geared diff and place this in the back. I have noticed that the Front diff spur gear is Wider than the Rear, so does this work alright, and whats the reasons for doing it? (Very confusing)

I plan to use JB Weld to lock the diffs. Would Blue tack work if I did not want it to be permenant?

Also, can you tell me does the motor need to be run in?

Finally, can Tamiya thread lock, be safely used next to the plastic parts in the kit.

Thanks.

I'm not totally familiar with the Hummer chassis (CC-01 I think is the number designation?) but if it does have a ball diff up front and gear diff in the rear, I would certain swap them if it's possible. Before I did any mods to the diffs, I would try that first and make sure they're interchangeable.

If so, I would go ahead and lock the gear diff because those are easy to lock; just stuff JB weld into the spider gears. Blue tack or silly putty should work for a non-permanent locker. I would leave the ball diff open. Ball diffs are hard to lock and certainly can't be locked in a temporary fashion. A rear locker should be good enough for a trail runner and an open front diff will keep your steering radius reasonable.

You don't HAVE to run-in the motor, but it certainly doesn't hurt. An old-school method is to hook the motor to a 4-cell battery (4.8V) and dunk it in water. The water washes away all the particles as the brushes wear in. You could also just hook it up to the speedo and run it at half throttle for a few minutes and spray the motor with motor spray to displace any brush particles.

To lock the ball diff, remove the balls and clean all of the lube off of the gears, rings, ect. Then get some abrasive paper (I like 120 grit) and use the diff rings and trace out the rings on the rear of the paper. Cut out the traced formed and glue the abrasive rings to the diff rings (paper side facing the rings, abrasive side toward the gear). Reassemble the diff and then tighten it as tightly as possible.

Should work fine, I did this in my Stealth trannies when I raced dirt oval and when I started crawling as I wasn't a fan of the Pede tranny.

Thanks Guys.