I don't run TC, but yokomo buggies. they share diff components however.
What O-rings are you using on the outdrives? Black or red?
What grease if any was applied to them? The black molly grease doesn't really work to well with the o-rings and causes them to swell and be tight. I'd suggest you replace the o-rings and use a touch of green slime o-ring grease on them instead, as it won't react.
Removing the shim is releasing some pressure off the swelled o-ring by the sounds of it, confirming what I think.
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Team Yokomo - YZ-2CAL3 | YZ-2DTM3 | YZ-4SF2 | YZ-2T | YZ-2DTM Worlds | YZ-2DTM x2 | YRX-12 x2
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10electric | Batley Buggy Club | YORCC | RHR | MB Models
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