car logo

Peterbilt 387/Cummins ISX long term test

by Richard Henley

Peterbilt 387 class 8 truck review

First impressions of the new Cummins Turbo Diesel

In the middle of November I packed my chains, tarps and other related stuff into my 1970 Dodge pickup and hauled it all to Springfield, MO so I could leave the ranks of the homeless and join the ranks of the gainfully employed. The homeless bit is a standing joke; momma’s house came with 6 tires and we took them off when we parked it, mine has a few more than that, they don’t stop turning, and if they come off I have a large problem.

Variable geometry gained fame as “variable nozzle technology” with the Chrysler 2.2 liter Turbo IV engines. It lets the turbocharger act like a small unit at lower rpm, and like a large one at higher rpm, so it has both fast spool-up (and efficiency) and high capacity.

My new Cummins isn’t a Dodge Ram. My new Cummins is the Ram’s daddy, and I have to say, if the Cummins in the Ram does for the pickup world what mine does for the class 8 world, it’s a wonder Ford and Chevy can sell their junk. (There must be a lot of people who buy on price alone.) This sure isn’t your daddy’s Cummins.

The big diesel is a Cummins ISX 445, displacing 15 liters, with dual overhead cams and a variable geometry turbo. I’m not exactly sure what variable geometry is, but the turbo is huge, and the valve cover is half the size of the redhead’s kitchen table.

The engine tag says it has 445 hp at 2100 rpm, but it must take a long time to get that far up the tach; mine seems to flat line at around 1600 rpm. The tag also mentions torque, and based on how it does the hills, I’m guessing it’s pretty close to the 1,700 foot-pounds it advertises at 1200 rpm. I couldn’t believe that number was for real at first, but my first load took me across US 60 and down US 63 from Springfield to Memphis, up and down the hills over the mountains and through the valleys, and this engine took stuff in high gear that used to require two or three downshifts in my last truck. US 63 in Arkansas is one of those roads that used to require a break every hour or so because your right arm got worn out from the constant shifting, but now I downshift more for small towns and curves than I do for hills.

cummins diesel engine

There are a couple of things with the new engine that take a bit of getting used to. One is the incredible torque real low on the tach. I’m used to the torque band starting around 12 or 13 hundred, and topping out around 1700 or so. As mentioned, this thing tops out around 1500, but it keeps on digging below 1000 rpm. I know Jeepers who are jealous.

The book credits its low end torque to the variable geometry turbo. This variable geometry stuff is also responsible for another thing that I’m certainly not used to in a big diesel, the absence of turbo lag. When you mash the go pedal, you get results right now! Immediately! With no messing around at all! This makes for a very touchy throttle, but I can live with that. (1700 ft lbs I could live with even if they painted it pink with lavender heartbeat stripes.)

Equally good as the power is the engine brake. I’ve used the famous Jake brake on quite a few different engines, with results varying by the engine. On some of them the engine brake makes a pleasant noise while operating but does little else; others work well at holding back a load on a hill.

Cummins ISX diesel engine

On this ISX, the Jacobs engine brake flat puts the rest to shame. You don’t want to use it at all with an empty trailer, it’s just too much. Down a big hill, you can get by with the low setting if you’re in the higher gears, but not at all in the lower gears. Loaded is where it shines, on a 9% grade with a gross weight of 73,500 lbs, it held the speed at 35 mph in 9th gear. In my last truck with the Series 60 Detroit, that weight on that grade required 6th gear and about 20 mph to hold it back.

With that much torque at your disposal, this thing gets real hungry in the hills when you use it. That’s not all bad though, because out in the flat land, fuel economy is actually increased. I can live with that, it’s not like I run the Rocky Mountain regional any more.

The new Cummins meets the new California emissions standards, and the truck has a pretty prismatic sticker on the door to prove it. There’s a minor irritation and a major complaint with that. The minor irritation is the DPF system, which is similar to the catalytic converter on a car. It’s a big can underneath the truck that has some sort of ceramic element in it that traps the soot in the exhaust. There’s a sensor hooked to it, and when the DPF gets full the turbo does something to heat the exhaust up pretty close to 2,000° to convert the soot to carbon dioxide. 2000° exhaust has the potential to cause some problems in some places. They solve this by installing an override switch so you can shut the system off if you are going into a building, or driving under trees, in a grass field, or parking on asphalt, or any other situation where it could start a fire. The driver has to remember to turn it off in those situations, and then remember to turn it back on again when the fire danger isn’t so high, or else the DPF gets full and you have a very expensive repair, not covered by warranty.

Cummins ISX diesel

To meet the California emissions and get the pretty prismatic sticker on the door, the truck also has to be programmed so that it won’t idle more than 5 minutes. Big trucks have auxiliary power units (APUs) to keep the interior comfy and let the fridge and TV work without the engine on. Wonderful plan, but what about when the APU fails and it’s 7° and the driver has to take his ten hour break (yes, I’ve already had it happen — twice!)? Hey, Parents Against Tired Truckers, how tired is that trucker going to be when he has to spend his entire 10 hour break restarting the truck every 5 minutes just to stay warm? P.A.T.T. had success getting the national DOT to make the hours of service worse than they were originally; maybe they can help truckers out with the EPA. If they would, I’d even quit wearing my Truckers Against Pissed Parents hat. (P.A.T.T. wasn’t really interested in eliminating tired truckers, and if they were they would have asked the truckers what changes to the hours of service regulations would help eliminate trucker fatigue, instead of asking some crazy sawbones what made truckers tired.)

The Peterbilt 387

On November 26 I took possession of a galaxy blue 2009 Peterbilt 387. Its not exactly a new truck but it’s pretty close, the previous leaser only put 65,000 miles on it, not much for an over the road truck. It still looks and smells new, and has most of the 500,000 mile/5 year warranty left.

I never really wanted a Peterbilt, they build a really good truck, but it’s kind of like a Harley. There’s an image thing that seems to draw a lot the kind of people that I don’t care for.

I really never thought I’d like a 387, as it’s based on the KW T2000. Trucker slang for the T2000 is “T too ugly”, and I think that’s a well deserved nickname, but I have to admit that the Pete designers toned the ugly down a bunch to the level of “just a bit odd.”

Now that I have a Peterbilt, I guess I’m going to have to quit telling the joke about the difference between a Peterbilt and a porcupine. I would tell some Freightliner jokes, but I don’t think there are any. I’m not sure if the reason is that the truck they build is the Freightliner joke, or maybe it’s just because getting stuck in one isn’t a laughing matter.

Peterbilt 387 class 8 truck

The 387 isn’t like the Petes of old; while it has a real wide cab like a cabover, it also has a hood. Not a very big one like the old Pete conventionals, but it does have a hood. I thought visibility out of the wide cab would be compromised by its width, but the Pete designers did an excellent job of designing the mirrors to cover most of the blind spots.

The designers did a good job in the suspension, too. The ride is incredible, but great ride is one of the Peterbilt hallmarks. My last truck was a Freightliner Century and I had a fancy computer stand that secured to the right seat and I had to secure the computer to the stand to keep it from jumping out on rough roads, and the ride was so rough that I had to replace laptops every couple years and rebuild the stand frequently. In this truck the computer sits on a pair of milk crates stacked up between the seats, rough roads don’t even move it around.

The interior is nice and overly spacious, but it’s a bit shy of storage space. The model 379 Petes were really well designed in storage, for having such a tiny cab and sleeper they made excellent use of every square inch of available space. The 387 has a huge cab and sleeper, but doesn’t seem to have as much storage as the 379, or (as much as I hate to admit it) the Freightliner Century.

Peterbilt cab

Interior construction and materials are classic Peterbilt class. The plastic is nice looking, solid with an expensive feel. The dash is full of pretty chrome ringed gauges and nice looking switches, all in a good position for visibility and accessibility. Actually a bit too visible at night, I wish the dash lights would dim a bit more. The lowest setting is a bit too bright, but I can live with it.

The seating position is excellent; I’m thinking they must have given the ergonomic dummy the day off when they designed this truck so it actually fits the range of sizes real people come in. It’s really nice to be able to reach all the controls comfortably without having to have the seat so far forward that my knees are in the steering column. Due to the design of the truck the seat is a lot higher off the ground than other trucks I’ve driven, that probably helps with the outside visibility but it does make the 13’9” overpasses that are common on the east coast a bit spooky, it looks like they are eye level when you are approaching them.

One thing that concerned me a bit was that the mirrors are viewed through the wing windows, and the wing windows are solid mounted and don’t open. Opening a wing window to see a mirror is a quick and dirty trick when the window is fogged up or covered with grime from driving on a bad road, but that’s really not a problem on the 387, the defroster keeps the inside of the window clear in even the worst winter weather, and the aerodynamics of the truck keep most of the road crud off the windows.

The downside is, it has the typical “aerodynamic whistle” at road speeds, only a problem if the windows are down, but in nice weather I like to run with the windows down. The heater is excellent, at near zero temperatures you don’t even need it on high. Air conditioning seems to be pretty good too.

The new truck has a Rigmaster auxiliary power unit on it. The APU is actually a 2006 model, and has actually been out to service more than it’s been operational since I got the truck. Apparently Rigmaster has gone bankrupt and that is making finding parts on the road a problem. Talking with other drivers that have had a Rigmaster, these have been troublesome even when new. A word of advice for anyone shopping for an APU, get a Thermoking TriPac, don’t get a Rigmaster.

Peterbilt 387 dashboard

Outside of the engine, my favorite thing about this truck is the galaxy blue paint. It’s just a bit lighter than the 1970s Plymouth B5 blue, an incredible color in bright sunlight, and good in any lighting. It has some funny stripes, a bit large for pinstripes, but not large enough to be real stripes. I’m guessing that’s the trend, but I sure miss the days when big rigs had big bold stripes. The body design is actually quite nice in spite of the big odd shaped grille, and the truck actually looks longer than it is.

The windshield is a minor drawback, due to the high curvature the wipers tend to freeze up pretty bad, and they leave a big unwiped spot in the middle when they do. Being a big one piece glass, I’m sure it’s going to be a pretty penny to replace when it gets chipped up.

Probably the biggest drawback to the truck is the weight. With my last truck I could legally scale 49,500 lbs if I had one of our lightweight Reitnouer MaxMiser trailers; this new Pete will only allow a bit over 48,000 lbs of payload. Considering some of our loads pay by the pound, that is apt to hurt the income a bit. Fuel economy will make up for a lot of that, though, and if the maintenance costs are as low as I’m told they should be, I might actually come out ahead of the game.

That’s the good and the bad, now for the stupid. First in this category is the QualComm satellite communication unit. The new version has a touch screen and it’s supposed to have the feel of Windows so “it will be easier for a driver to use,” and it talks to you so you don’t have to look at it while driving. Whoever thought a touch screen would be a good idea in a flatbedder’s truck really needs to get out of the office and see what we do for a living. The touch screen still works fine, but after only a month, visibility in some parts of the screen is a little hazy. The programming does kind of look and feel a bit like Windows…version 3.

truck tractor

The biggest problem is the talking. First is the voice, a feminine voice that is supposed to be soothing, but sounds just like one of my ex-girlfriends at the wrong time of the month. The second problem is that QualCom charges by the character so we use a lot of abbreviations, like your teenage daughter when texting. The device does poorly translating these abbreviations, so most of the time what it’s saying doesn’t make any sense and you have to look at the screen.

And I really hate the nanny systems. Let me start by saying that if a driver really needs these “life saving” systems, he probably shouldn’t be driving, because if a situation activates any of these systems and you aren’t already responding to it, it’s already too late. I wrote about these in a recent article.

I’ve not gotten a chance to drive the new Ram Cummins Turbo Diesel, but if it’s half as good as my new Pete Cummins Turbodiesel it’s got to be one heck of a truck. If you need just a bit more truck than the Ram offers, give the 387 Pete a look. I don’t think you’ll be disappointed, so far I’m certainly not.

Keep an eye out, if you see me out there, give a wave. I’m not even real picky about how many fingers you use when you wave, although all 5 would be a bit nicer than just the middle one. If I’m not too busy fighting with traffic or the nanny systems, I’ll wave back.

Also see: maintenance • exhausting problem

car review

Key Sections

Home

Articles

Car Reviews

SUVs/Minivans

Pickups and Big Rigs

Newest Features:

Infiniti G37 IPL: hot convertible

Ford Flex: smooth modern wagon

Dodge Dart: hot handling, great gizmos

Preventing accidents with amber turn signals

cars

News