This week's 'Ask Evan' question comes from Tammy F who asks, "Why do mail trucks have such a distinct sound when pulling up to the mailbox? No matter what else is going on inside, I can always hear that familiar "putter" sound when the mail is delivered?"
The U.S Postal Service has used the same delivery trucks for the past 30 years. The USPS runs about 200 thousand Grumman Long Live vehicles all over the country. They are known as LLV's, which many recognize as the boxy little trucks. The truck still in use today was built on an aluminum frame with a 4 cylinder engine from a 1980's Chevy S-10 pickup truck.
That's part of the sound difference. Not too many 4 cylinder 2.4 liter engines powering small old trucks these days. The LLV was first put into service back in 1986. The last one was actually manufactured was in 1994, so their service life is at its end.
The USPS is supposed to roll out its new fleet sometime this year. The vehicle that will replace the LLV is yet to be announced, but electric vehicles may be part of the plan. We may find out soon, and eventually the familiar sound of the mail truck outside your home will likely fade.
Remember if you have questions you'd like to ask send me an email to AskEvan@FOX43.com. Put 'Ask Evan' in the subject line. You can also reach out to me on my Facebook page, Evan Forrester FOX43. Whatever the topic, I'll do my best to track down the answers you are looking for.