I became interested in the GM PD - 4106 in 2018 after reading a lot on the internet. When GM built that bus in 1965, GM had not yet become GMC; I think that happened the next year. The PD - 4106 was heralded as “The Sports Car of Busses” because it handled so well, was easy to turn around, and had a lot of power and airbag suspension among lots of other features. It also had an “Art Deco” look. I like “Art Deco”.
I was sixty-eight years old and in good shape. I was tired of doing all the work on my five-acre farm in Arlington, Washington. So, I was selling the farm and keeping an eye out for a good PD - 4106.
I planned to fix up a bus as a motorhome and travel to different festivals around the USA and maybe Canada. Eventually, in 2019 I found a bus that looked promising in San Diego, California and after speaking with the seller I flew down there. My bus adventure was beginning.
The seller was not around but her sister and husband were, so we got together and visited the bus. It had a good paint job and the tires looked okay. The headlights and turn signals worked and the engine, a Detroit 8V71 started easily. I was excited and liked how the bus floated down the road with the brother-in-law behind the wheel.
The airbag suspension was nice, the thing rode like a Cadillac. I had never driven anything as big as a thirty-five-foot bus but now was the time. Wow, careful on the turns and no tailgating for sure. The brakes worked well, and it had plenty of power driving with the very desirable Allison V730 automatic transmission. It was truly a thrill.
The bus I purchased had power steering and an automatic transmission…perfect. The engine was hardly heard, as it is way back there at the back of the bus. A bus with the engine in the rear is referred to as a “Pusher”. Nice. The headlights were a newer type of super bright LED, more about that later... There was one major thing I did not like, the Steering!
There was major play in the steering wheel, like five inches in either direction. The sellers said, “Oh you will get used to it!” I thought, “like hell, I will”. If I get this bus, fixing the steering will be the first priority.
The inside i.e., the living quarters was not really that great. The headliner was old and so was everything else. Maybe it was converted in the 80s and is really worn and dated. I did like the cabinets in the back of the bus, i.e., the bedroom and the hallway closet were okay, but the bathroom shower was going to need a rebuild and the wall was too far into the kitchen area in the middle of the bus.
The electronics for converting 12V to 110V were primitive. The windows were not perfect but pretty good.
The kitchen was going to need a total rebuild and the heating system was a diesel burner in a storage compartment that smelled bad and was noisy, all that just to produce hot air for the bus.
About the storage compartments: One of the biggest differences between school buses and touring buses is that (most) school buses lack storage compartments. This type of bus has storage compartments for most of the length of the bus. They were originally made to haul suitcases and freight so some of the compartments extend all the way across the bus and others are halfway on each side. The bus had a good couple of water tanks in the storage area, one for “gray” water and one for drinking water.
There was no blackwater tank as the bus was waiting for a compost toilet. Having a blackwater tank means you must empty it at a dump site and that means if boondocking, you must break camp and drive to a dump site to do it…and you lose the storage space that the black water tank takes up. Phooey on all of that.
Modern compost toilets have a built-in fan that vents to the outside and they don’t smell, they are amazing, and the maintenance is low. I put in a Nature’s Head toilet when I redid the interior and was very happy with it... The bus had a worn-out water heater and the plumbing overall looked like a mess.
I didn’t mind the fact that I would have to trash a lot of the conversion as I had my own ideas about how a traveling musician’s home should look. Well, I bought that bus in San Diego and ventured toward I-5, the freeway that goes from Mexico to Canada and through California, Oregon, and Washington.
I missed the on-ramp, and a bit later crossed the coast highway and was going to turn around easily in front of a motel but then realized I had misread the layout and was going to have to do a lot of back and forth to get turned around. A very kind and perceptive woman saw my difficulty and gave me directions for getting turned around.
I made it back to the on-ramp and got onto I-5 and was immediately in the middle of San Diego stop, go, stop go, rush hour traffic. I persevered and eventually made it into Los Angeles rush hour traffic which was just as bad. Shoulder to shoulder and bumper to bumper I was driving a large bus but doing okay too.
Eventually, traffic became much less congested. Now I was driving in the desert and headed for the infamous “Grapevine” section of I-5. Climbing the mountain with an eye on the temp gauges, one for transmission and one for engine temp we headed up…and up.
Okay bus, what cha’ got for power?
I was doing about fifty on the steep climb and was damn satisfied with that. Maybe I could go faster but this was plenty for the first time and an unknown engine. When I checked the serial numbers on the Detroit engine much later, it turned out the engine was made in 1983, and because of the power, etc. I think it’s in very good shape.
Eventually, I made the summit and then headed down the other side! The Grapevine has escape ramps of sand for runaway vehicles and I most certainly did not want to use one. So, I was just a bit cautious about the downgrade, but I did ask my bus, “So, baby how’s the Brakes?” Well, they turned out to be just great and later I found the shoes were in like new condition, and still are too! Well, I had made it past the Grapevine and then a lot of easy driving to Northern California and the foothills of the Siskiyou Mountains. They extend from Mt. Shasta in California and are a great way into Oregon.
I would have to say the Grapevine was no big deal compared to the Siskiyou mountains. Steep, windy, and up and down for hundreds of miles. The newer type of headlights the bus had reflected a strange and unpleasant light back at me from all the signs on the roadside, the bigger the sign the worse it was. I was driving much slower and the big semi-rigs that were constantly passing me, but I deemed that much smarter than trying to equal them.
My beginner level of experience and the loose steering kept me in the slow lane. Running on caffeine and excitement I drove through the night and somewhere in Oregon or Washington I realized I was sleepy and in stop-and-go traffic so I pulled into a rest stop, parked, turned off the Detroit Diesel, and fell into the bed and slept like a log.
I got going after some sleep and rolled back onto I-5 for the final leg home. The engine had become quite loud, the night before and I had checked the exhaust system. In this type of bus, the muffler is mounted vertically next to the engine and is sometimes referred to as “the trash can” as it does resemble a trash can. It had come loose from the manifold and was not muffling much but the situation didn’t seem harmful, so I continued and was glad the unmuffled engine was in the back of the bus.
Eventually, I got into rush hour traffic in Bellevue, Washington. Bellevue is a rather new city, that seems very chic, upscale and a bit on the snobby side of things or so say we that do not live there. There are a few tunnels I had to pass through. Let me tell you, going from a standing start in rush hour traffic in a tunnel with a Detroit 8V71 Diesel and no muffler is beyond loud. It is LOUD and deep down I truly enjoyed it. Another sixty miles or so and I pulled into the large parking lot at my farm and my first bus journey was complete. Good Bus!
During the winter I hired a mechanic to help with some wiring and mechanical needs. It’s a large list of all that was added or replaced in the bus, and I’ll try to get it all told. The driver’s and passenger’s seats were old and ugly, so I removed them. I bought some great-looking, comfortable seats on eBay. I paid around five hundred for the seats including shipping. I also rebuilt the pedestals for the seats as needed.
The driver’s seat is electric, and the passenger seat is manual. I replaced the gauges and spent roughly $800 on them. I ripped out the headliner in the driver’s area and installed a modern type of black headliner. Then I replaced the headlights with expensive and possibly the best money can buy.
One thing the bus had that I liked was the parquet oak floors, but I had to add more because I was changing the floor plan. I removed all the hot air vents in the fakir from the previous heating system and I removed that heating system entirely. I removed the old headliner in the “living room” and installed several expensive tapestries I bought years before. They are unique works of art and cost approximately $1,000.
The bus roof is arched, and I used bent stainless-steel bands to press the tapestries to the arched ceiling. Above the windows are gold-painted stamped tin runners that match the stamped tin ceilings in the kitchen area. I installed LED lights on dimmers throughout the bus in the ceiling and above the kitchen’s windows and counters. The LED lights are soft LED lights with less blue light than the cheaper LED lights that are rather harsh.
The ceiling is stamped gold tin and has a new ceiling fan of high quality. The kitchen ceiling is also stamped gold tin and has a ceiling fan also. Electrically speaking there is a lot of wire in a bus. If I was to do another bus of this vintage, I would rip out all the wiring and start fresh with wire that looks like a modern wiring harness, i.e., there are about ten wires of different colors joined side by side, I forget what that is called but I ran many separate wires and spent a lot of time on wiring.
In the kitchen, I wanted cabinets that would lock so that drawers and doors wouldn’t be opening and crashing around while driving. I chose two stainless cabinets with thick butcher block tops, one for the sink side and one for the cooking side. The cabinets cost close to $2,000. On the cooking side, I cut a hole and mounted a double-burner stainless cooktop. On the sink side, I cut a hole and mounted a small stainless sink and faucets. The kitchen functions and looks very good.
Just past the kitchen in the hall is a new Frigidaire stainless refrigerator, apartment size. I always had more fridge space than I needed. There is wood cabinet storage below and above the fridge. The fridge was approximately $250. I installed a cheap “instant-on” water heater, (eventually I replaced it with something better). I did a lot of rebuilding to improve the small bathroom. I’m 6’1” tall and I fit just fine in the small shower.
Buses usually run on a 12 or 24-volt system. Mine is a 12-volt system. So, to run anything on 110 Volts you need a converter. To charge batteries you need a charger when plugged into solar or shore power. I installed a “Magnum” charger/converter. That’s first class and has worked impeccably.
The compartment for the bus batteries has six 12-volt sealed batteries. They have proven to be trouble-free and very adequate. For running anything else inside the bus living quarters there are four large-capacity Lifeline batteries, costing approximately $1,500 as they were used for a year before I bought them. I paid less than half price and they have had no issues.
This story could get very long indeed but I have a bit more to go. Leaving Washington State, I drove to Coolidge, Arizona. I had purchased a “parts bus” there. It had a good engine and a lot of parts that I wanted for my bus. The parts bus has things like the door crank, overhead metal door, door panels, window wipers in good condition, etc., etc., I transferred it all to my bus.
I installed solar panels and purchased a couple of classic MidNite solar controllers as well as some small battery gauges. I also built a wall between the driver’s area and living quarters. On this wall, I mounted all the solar controllers, etc. This has worked out well.
My next journey started as COVID-19 was starting to take over the country. I Landed in Flagstaff, Arizona. I parked in the woods and continued fixing up the bus. It was extremely dry there and forest fires were a threat. I left just as some fires were spreading in the area and I drove the bus toward New Mexico.
One of the best experiences I had with the bus was driving until I was tired and then pulling into a rest stop, parking, then turning off the engine, and being home! Fixing food, reading, listening to music, and sleeping in my own bed was a real pleasure… I drove to Madrid in New Mexico and that’s where the bus is now.
I had read that you really can’t run air conditioners from a solar setup. Well, I didn’t like the air conditioners that many RV and converted buses have. They lower the ceiling… so I bought two small window A/C units and installed them in openings I made on the driver’s side of the bus, one in the kitchen and one in the bedroom. I found there are limits to my solar setup.
The solar panels work very well but on a cloudy day which is thankfully cooler, A/C use can be limited, and I did not use the A/C after the sun went down. The units stick out from the side a bit but are easily moved to mostly inside the bus for travel.
One of the biggest improvements I made to the bus was to the engine cover, sometimes referred to as the tailgate. This type of bus and many similar busses has a tailgate that opens to a horizontal position about five feet above the ground. It’s a horrible idea.
To not bang my head into the thing was almost impossible so I made some changes. I cut it into three pieces. The side pieces have taillights and are hinged to swing out like little doors. The center section is very light and swings up and latches against the back of the bus. The result is wonderful for access and visibility and no more head injuries.
The bus needs some wiring improvements and some minor carpentry, etc. The propane piping is good, and the bus is pretty toasty when it is very cold because I converted a wonderful heater made in Japan for the bus. The heat exchanger is amazingly efficient. I have lived in my bus for more than two years and I have really enjoyed it.
The water tank holds about 90 gallons, and if you can be conservative when you shower, it lasts for weeks, even close to a month. I never plugged into “Shore Power”, never needed to. However, the bus comes with a long industrial power cord.
The gray water is easily drained and was good for plants but of course, could be hooked up to an “official RV” drain with little effort. I towed my Dodge Grand Caravan on a tow dolly for my travels from Washington to Arizona and New Mexico. The bus didn’t mind.
This bus has new air horns, i.e., Train Horns on the roof over the driver’s air throttle and a new pedal valve, so smooth!
My plans for driving to music festivals had run into a snag even bigger than COVID-19. I was losing my sight from a disease called Glaucoma. One eye was blind, and my good eye was having serious issues. I no longer felt I could be a safe bus driver. I’m not playing a tiny violin here. Stuff happens in life, so it gets down to “do your best regardless”. So that is why I’m selling the bus.
To see the classified listing for this bus, click HERE.