Paccar Engines

Why do Paccar engines get so much hate? Just curious as I plan on one day purchasing my own Kenworth. Are they really that bad?

Not sure but both the KWs I've driven for my company have the Cummins X15 in them. It's really difficult to get an accurate bead on the performance aspect because as company trucks, they're set up for maximum fuel economy. Both trucks, a 21 and next gen 22 have been extremely reliable. I'm assuming the paccar engine would be as well, if I understand correctly, it's basically a Cummins in that the ECU, fuel delivery system and much of the motor is the same.

I can't answer your question about hating on Paccar engines. I obviously don't read the stuff you do, but then I've owned my share of trucks - enough to know I don't want to own another one!

Drew whoever orders the truck from the manufacturer determines what engine goes in it. You don't have to have a Paccar. It's kind of like Burger King - you get to have it your way. When ordering trucks, the manufacturer really just builds the frame and body. The engine manufacturer is a separate entity. Yes, Paccar Kenworth and Peterbilt have a connection, but there is no requirement that they are mated together. You choose the brand and size of engine and transmission.

It's more about certain years that had issues. For example.... My 2017 international had an Allison AMT transmission. Because that was the new year, there were glitches, it was a problem. They bucked when backing and often didn't shift correctly. There would be air pressure loss that preventing the shifting. My 2020 International had an Eaton transmission and was great... However we were 3 years into the AMTs and they were improving.

My friend had an Allison in a different model and year and it was fine.

Paccar had some issues in the Pete's about 2012 in manuals, I believe. Again, that was a "change year" as DEF was being put on the trucks. Even here at Prime many of the trucks before that did not have DEF. Many of the grumbles I hear from the experienced drivers then were about that. And the engines at the time were Paccar, so it seems paccar took a brunt of the hate.

Just a guess and my own observation.

It all really depends on who you talk to. Here is what I know from speaking with mechanics.

The Paccar motor is wholly paccar. IE Kw/Peterbilit. It is their own motor and design. It has a tremendous amount of additional sensors on just about everything as compared to other brands. The ECM’s are locked and cannot be accessed by anyone but them. In 2018 they developed a system where shops can buy additional software and get limited access, but it has to be done through their server and any changes must be approved by Paccar.

The routine maintance is more expensive and paccar says the overhead should be run every 100k miles. That is crazy to me.

I love my Pete, but it has a cummins in it.

Old school, that is some good information.

I was just curious about the motors because I want to learn whats what before I buy my own tractor way down the line. Just seems like every corner of the internet when it comes to trucking says to avoid Paccar like the plague. I knew I would get rational information here. Which is why I asked.

Here's something you can research. How many Kenworth and Peterbilt tractors are powered by Paccar VS Cummins powerplants?