USPS trucks don’t have air bags or air conditioning. They get 10 mpg

The Grumman LLV's that are still running are often monuments to mechanical genius that are worth studying. Years of "it's got to be rolling tomorrow" inspired hacks stacked up.

If you're looking to find a mechanic's shop to patronize, look for the one that services the area's LLV's. Ask the Postmaster if need be.