new truck advice

[Linked]

I'm looking at buying a new truck new to me. I see a bunch of Paccar MX 13's I was reading a little bit about them it looks like the 13th might get a little bit better fuel economy. the other big engine I see is the Cummins ISX 15 I'm not too sure which one is more reliable which one i should buy the other factor on this is I drive in the mountains 90% is in the mountains I'm thinking the Commons isx 15 bigger mass better Jake brake that's just a guess!! wanted to put this out see what you guys thought which one might be better for my situation dry flatbed so I am always heavy and 25% of the time need over Wait permits maybe asking I’m asking the wrong questions

[JimT]

is this going to be your first truck? You sound a bit new. Give the "My Book" a read through. I'm no expert here, but if you're heavy a lot in the mountains then the larger displacement engine (15 liter instead of 13 liter) is probably the way to go. All the engines have problems and need constant maintenance. The biggest reason to choose Cummins is that anyone can work on it, especially yourself, and parts can be obtained nearly anywhere. Other engines are tied to only a single truck OEM, limiting your service options.

Engine aside, if you're heavy pulling mountains then one of the biggest things you will need to focus on will the the gear ratios. probably want a 13 or 18 speed transmission and the rear end ratio will have the biggest impact on long term fuel efficiency and engine life. I'm not as well versed in the ideal ratios so hopefully someone else will chime in.

Take LOTS of time and spec your truck to match YOUR workload, THEN go shopping to find a truck that meets your needs. Make, Model, year or even engine won't make much difference if you don't do the research ahead of time and get the right equipment for the job.

As far as preferences go, this is mainly a Cummins maintenance related forum, so most of our opinions will be biased to reflect our experience.

[Rawze]

Like JimT said...


* If your buying used,.. you need to take a hard look at being able to work on it yourself so you do not get rapped every time a check engine light is on.

The cummins's only real advantage is this fact. Otherwise, close your eyes and choose whatever ill-begotten engine you want to because they are all going to be acting up by the time they get half million miles on them.

I.E>> sounds like your asking the wrong questions.

You should heavily be asking yourself...

* What would be the proper specs for a truck going to pull big hills all the time, loaded heavily?

* What truck make/model for the type of operations your going to be doig with it?

* What engine is going to give you the least operating costs vs. longevity, dependant on how much your willing to turn a wrench on it,.. or be a dumbarsse trucker who runs off to the loacal repair shop every time the emissions system burps and acts up, wasting time and money all the time?


-- I.E> The only advantage of the red engine (cummins) IS the fact that you can learn to, and gather ALL the proper tools and software to work on it yourself. All diagrams and repair procedures, parts lookup catalogues, all are FREE from the engine maker, etc... - That is its only advantage to owning it.

-- you should not even be considering "what is best engine for mountains" because that it TRUCK RELATED, not engine related.

-- Mountain driving == 13 or 18 speed tranny, and a set of rears made for it. 3.79's, 3.90's, 4.11's, or even 4.36;'s ... anything taller than about 3.55's and your pissing up wind and eating the hell out of that engine all the time and it significantly increases your long term operating costs. -- The truck MUST be geared right for the work at hand.

-- the there is learning how to drive it as such. -- Installing pyro and boost gauiges, learnign how to actually drive by those gauges because you now own it instead of driving it with the goddamn cruise control on all the time and mashing your foot in the floor, and lugging the engine below 1500 rpm's because that is the ignorant super-trucker idiot, truck/engine killing mentality any more it seem.


those are my first thoughts on it any ways. I have had my fair share of driving in those regions and do very well.

[hhow55]

When I used to run the rocky mountains, I had 3.90 with a ten speed tranny, and it served me well. Being you hauling heavy, I would suggest going with 4.11 rears. What is your maximum gross weight?

[amermextrucker]

Listen to these guys, but also when you have your sights on one or two send an oil sample out as well and when you settle on the truck you want to purchase request a dyno it will most likely be at your cost, but that will give you a good idea of how the engine is pulling and also it will measure blow by. Just a suggestion.

[Linked]

Thanks for all the response. sorry I didn't respond faster I didn't see anybody had responded then I gave up. so, to answer one of the questions I’m usually am around 95,000 And I agree gear ratio has a major effect I currently have a 378 Gear ratio 10 speed Mercedes engine no Jake brake. hence the real reason why Jake brake is on my mind! wondering which engine has the strongest Jake brake. One if the trucks I’m looking at does have a 13 speed in it 355 gear ratio dd15 505 hp. And yes, working on your own truck is the only way to go. Taking my truck in to a shop would have put me out of business right after I started. I don’t relied on shops not only for the money but also the time that it takes them to do a repair. I can usually do a repair overnight and be back on the road in the morning or on the weekends. I appreciate the info on The Commons having support for that engine direct from the manufacturer is awesome Does anybody know of a forum that works with a DD 15?

[tree98]

(05-04-2020 )Linked Wrote:  Does anybody know of a forum that works with a DD 15?

Just buy Cummins, make your life easier.

[Linked]

(05-04-2020 )tree98 Wrote:  

(05-04-2020 )Linked Wrote:  Does anybody know of a forum that works with a DD 15?

Just buy Cummins, make your life easier.

you mite be right this has been a good forum lots of info witch should = profit the problem that I have found is nobody is selling there Cummins for a reasonable price

[Mattman]

Cummins engine equipped trucks do seem to come with a higher price tag.

May be a reason for that.