Building the Tamiya M-05 Ball Differential (#54194)

When I bought the Tamiya M-05 PRO (second-hand) I realised during the strip-down that it had a M-05 Ball Diff (Tamiya Part #54194). Unfortunately the diff outdrives on the diff were badly ‘notched’ so would need replacing. I couldn’t find identical replacements but I did find these outdrives which are identical with the exception of being made from hardened steel.

I built the diff as per the instructions...

M-05 Ball Diff Instruction Sheet

Check out the pictures below to see how I put the diff together:

Diff Joint (B)

Added Diff Washer

Added 850 ball bearing

Added 0.5mm spacer

Added Diff Pulley - note pulley orientation so that you can press balls into their sockets

Added balls to pulley

Added 850 bearing

Added Diff Washer to Diff Joint (A)

Fitted both Diff Joints together

Fitted thrust race to diff bolt

Fitted the bolt & thrust race to the diff and inserted the nut and tightened it down - Diff built!

That’s it – when I tightened down the bolt I used a pair of hex wrenches to keep the outdrives steady while I checked if the diff was slipping by trying to turn the pulley. I built mine so it only JUST slips. I’m hoping this will give me good drive out of corners without too much understeer. Only time will tell!

For the greases and lubes used in this build, I used what was already in my toolbox, however if you need to find them then I can recommend these:

Muchmore Thrust Grease

Muchmore Diff Grease

Next post will cover the build of the #54000 Tamiya M-Chassis shocks. See you next time!