Looking for real world feedback on the PACAR MX 13

I have a 2012 with 433,000 on it. My main complaints are constant check engine lights that nobody can solve and the fact that your pretty much forced to go to a Paccar dealer if you have and engine problem because of the Davie tool that DAF105 mentioned.

So far I've had a water pump (warranty), steering gear box (not engine related) and DEF doser and DEF lines go bad. The lines were covered under warranty but I had to pay for the doser, DEF filter, and a NOX sensor. I also occasionally get a miss (don't know how else to describe it) when I'm pulling a hill. Maybe every 2-3 months. I've had them check for issues with the injectors, turbo, etc and they can't find anything that would cause this mystery problem. I seriously doubt I would buy another one.

 

How much MPG are you getting?

 

My average is right around 6.25 but I'm in the mountains a lot and run 70mph way too much. In CA with the lower speed limit I usually am closer to 7.

 

Another thing I would mention, I have 3.36 rears with a 10 speed ODD and I am sure this truck would be way better with lower rear ratio or a 13 speed. It really dogs out in the mountains but I think that's mostly gearing and not the engine.

 

How about some update I'm about to buy one 680 with mx13 at the end of the year

 

MHC Kenworth in El Paso been pretty good at getting our T680s in and out of their shop. They usually send a couple of guys over to pick the trucks up. About the only gripe I hear from drivers assigned one of them is the lack of room compared to the Volvo 780s. Other than that they said the MX engines pull about the same as the Volvo D13's.

 

We are fleet of 25 trucks, we currently run 18 MX engines from 2012 through current version in KW 660 and 680. The mx engine is very solid, good economy but all the crap bolted onto it is the issue. From the aftertreatment system which is a joke, the DEF system is in constant failure mode and the wire harnesses are always causing issues. The trucks throw codes like pitchers throw baseballs. Paccar tech support is so poor we wont buy any more of these. We average 2 1/2 days down for ANY issue, often it is a reprogram issue which almost always causes another issue. Tech support is so slow responding to the dealers and have them check so much stuff without reason it is difficult to get your truck back once it goes into a dealer. I have finally taken to telling them what to fix, paying the bill regardless of warranty and getting my truck back on the road. I would strongly urge you to look at any other platform as an engine if down time matters to you at all. If they could fire all the tech support staff and let the dealers just get in there and repair these things turn around time would be much better. We have had one truck at the local dealer for almost a month with tech support having them change one item after another trying to get over 900 degrees regen temp. They are currently close to $18000 in repairs and it originally went in there for a turbo leaking oil. We had another truck went in with a code for the lambda sensor, 5 days later, 2 injectors, 1 pump, 2 nox sensors they finally changed the lamba sensor and fixed the issue. Tech support sucks and if the dealer steps around the procedure it voids the warranty repair and the dealer eats the extra stuff they did not approve. We are done with Paccar products. Test driving Volvo and Freightliners, we may go with cummins in the KW but we certainly will NEVER buy another MX engine because of tech support.

 

Seems like there is a lot more negative feedback on these engines than positive. I was considering a used ('12) 587 over a newer ('14) shaker simply because I'm getting older and I do believe the Pete's ride better. But I'm buying this truck, and can't really afford any more do overs if I choose un wisely. The DD is a known quantity to me, beat it with a sledge hammer & as long as you do the scheduled maintenance it will run a long. long. long time. I know what kind of mileage I will get with a shaker as well, roughly. Plus its far easier to get parts for and get serviced. The Pacar is unknown to me for MPG. Sounds like it leaves you down far too often though. Please keep the intel coming. Thanks everyone.