Curbside Outtake: 1960 GM PD-4104 Coach – It’s Taken Up Residence In My Neighborhood

My favorite vintage coach took up residence in my neighborhood well over a year ago, and we still walk by it every few days. And clearly someone inside has made it their residence, including a little chimney that appears during the winter season. Got to stay warm.

I used to really want one of these in my younger days, before I realized that it was too big for where we like to go. So I’ll just admire it as we amble by, and imagine all the places it’s been in its long life. Was it a Greyhound bus? Or Trailways? Or one of the many other operators back then? The PD-4104, rightfully called “The Most Dominant and Influential Bus Ever” in Jim Brophy’s excellent Bus Stop Classic, was also extremely well built, so it’s not surprising folks are still using them, one way or another.

Let’s get my only gripe out of the way first: I’m not a fan of the driver’s door that was cut in as part of this conversion.

It defaces the very nicely-styled driver’s window, one the best details of this handsome bus. The short story is that the PD-4104 completely revolutionized the highway coach market when it arrived in 1953, with its air suspension, advanced styling, light weight monocoque body, and its exclusive 6-71 Detroit Diesel engine, which was lighter and more powerful than the competition. Every other coach instantly looked old-fashioned and obsolete.

And of course, it spawned the legendary Greyhound PD-4510 Scenicruiser, which obviously was essentially a lengthened PD-4104 with a lowered front section and raised rear. That led to some structural issues, and unlike the absolutely unblemished reputation of the 4101, the Scenicruiser had a rather rough start in its early days.

It’s very common to have the design of the Scenicruiser be attributed to Raymond Loewy, when stylistically it’s really just a chopped and stretched 4104. Loewy did design a couple of concepts for it, but the final version is essentially all GM Design.

These shots were taken last winter. The stove pipe came down in the spring, and has recently sprouted again.

Sadly this conversion eliminated all of the original windows. Oh well. I’ve seen some fine conversions that eliminated one, or maybe two, but not usually all of them. Not exactly very handsome anymore.

The gracefully curved rear window is gone too. Only the fluted lower body is mostly intact.

This is why I know what year it is. And that makes it the last year of its run, as the 4106 replaced it in 1961. We’ve yet to do a post on that, but it was essentially an updated 4104 with the new 8V-71 engine, which made it zippier, and also allowed the air conditioning to be run directly from the engine, instead of its own small pony engine in the 4104. The 6-71 didn’t have enough power to run the a/c directly and still maintain highway speeds.

Speaking of, this bus still has the original engine and four-speed manual transmission, as I did see it being driven off one day. It’s been a long time since I heard (and saw) a 6-71 and manual transmission bus take off. It’s not exactly a pretty sight, inasmuch as these buses were quite modestly powered with all of 210 hp on tap, and not a very low-geared first gear. Lots of noise, a fair bit of smoke, and a slow take-off. And then of course a substantial gap in acceleration, as the operator double-clutches into the non-syncro second gear. And then another bit of thrust…and so on…

But eventually these buses did make it up to 60+ mph. It’s just that the time to get there was measured in minutes, not seconds.



CC: GM PD-4104 – The Most Influential and Dominant Bus Ever   Jim Brophy

CC: GM/Greyhound PD-4105 Scenicruiser    PN