I have a 91 sy and I am wandering if it will damage anything to remove the front driveshaft to do a dyno run and some tuning? I know some cars it affects the transfer case if the front driveshaft is removed.
nope, but it would be a good idea to change the xcase fluid after doing such dyno work or anytime you drive without the propshaft. just take a drive with the propshaft and take a feel on the xcase. it gets mighty hot under there and only around 1.5qts to keep it all cool.