I advise everyone listen to CMG.
I've worked "both sides" myself. There's no point in getting into "tit-for-tat" battles over every mistake. Face it, both departments make mistakes that cause problems or extra expense for the other.
I suggest letting the little stuff go by and reserve "charging back" to either department for the more serious instances....and then after a discussion between both managers. In other words....pick your battles.
If any service or parts manager REALLY wants to make some in-roads, then next time your department makes a mistake walk up to the other manager and say "This is our baby. We blew it. I expect you to charge me for that." Its called "taking the high road" or "putting your best foot forward". Whatever you call it, it'll go a long way to mending relationships. Soon enough, your "adversary", be he parts, service, or b/shop manager, will feel like he has no choice but to put HIS best foot forward, too. After all, HE doesn't wanna be the one looking like a sh*t heel, right ?
Over a period of time....if everybody can conjur up the you-know-whats to step up to the plate and take it on the chin once in awhile without being asked to do so, then an atmosphere of trust and sense of fair play will develop. For example, our body shop and parts managers, along with myself (service) have all agreed that we can charge off up to $100 (per incident) to either of the other two departments based on nothing more than our own good judgement.
You know what? We hardly ever do it. Why? over a period of time you realize that things tend to even-out in the long run....so why bother ???
Anyhow, guys, that's my little schpeel for the day.
For the record the warranty reimbursement for shuttle rides might cover 2% of the actual expense.......
Cheers
DD