Checking out a TA on an 856

Is there any tests that can be run to determine if a TA is Bad, or just setup incorrectly or has 'bad linkage'? My 856 it works until it gets a load on it and then it starts slipping. From what I've read that is how they act when they 'go out' but I'd like to test it or check adjustments before accepting that.

Thanks,
-ron