C15 fuel economy and longevity

That depends on the year/ model of the truck/engine , the weight/size of the load,to a large extent. then comes the driver factor, which can affect mpg as much as 30% . speed is a major factor in mpg. Up to a 2003 model 6-7 mpg is possible but 5-6mpg is realistic. 2004 and newer a 1mpg decrease in mpg is normal. As far as expected life of the engine , the 2003 or older will go 800k to over a million miles depending on how well it has been maintained. The newer engines have many more maintenence issues with regards to the emissions systems and these issues add thousands of dollars to the maintenence costs of these engines plus the amount of miles to overhaul is shortened significantly (2 to 300k) the cost of an inframe overhaul on a C-15 will run about start at about $12000 (very basic ) to $20000 (catastrofic failure) . Many things are involved in proper upkeep of these engines , changing the oil is only the tip of the iceburg , and the history of upkeep affects the cost of upkeep greatly . Caterpillar is a very expensive engine to repair . there is a reason you dont see a lot of Cummins powered trucks for sale, the N-14 is one of the better choices if not the best choice for reliability, second would be the Detroit 60 series 12.7 L . The Cat will get you to the top of the hill first but you will pay dearly for that privilidge .

 

Welcome to the site if you were to search "C-15" or "Accert" you will find plenty of very usefull info.....believe me I read for literally hours one night and learned a bunch !!

Overall its NOT a bad motor but as the poster above stated yellow motors can be pricey when they act up....good luck..

 

Yep Yellow can mean lots of green out of your pocket .

All of them can be expensive, proper PMs and knowledge about your particular powertrain go along ways.

I am really impressed with the ISX offerings from cummins. They can be spendy also.

 

agreed, add engine history to the list of things you should research on the truck also..

I think IF I ever buy another truck it will be old enough to have a B model Cat screw all the electronics !!!!!!!!!!

 

My 2000 Century with a C-15 sucked a valve at 930K. Best thing that ever happened to it. 20K spent rebuilding it and turning it up to 500hp. I pull light loads on I 5 and am consistantly running in the low 9's for mpg. (I am a very hard core 55mph runner). IMHO running the engine at 1200 rpm is the key to great mpg. The truck is currently at 1.27 million miles. Not including the rebuild, I spend about 4K a year in tires and repairs. I'm on my 3rd starter, 2nd fan, had to have a new clutch put in (shortly after turning it up to 500hp..hmm).

Drive like everyone else, get the same result as everyone else.

 

I screwed up and sold my 93 T600 it had a C model and WAS a peak engine. I made it mechanicle and had no more issues.

Like I said I am really liking the Isx it pulls great and get 6-6.5 mpg at posted speeds maybe a hair faster.

 

What we've experienced with Cat is you can only get them worked on at Cat when it's new. And Cat is more interested in their construction equipment in most places. They made us jump through hoops with our tankers that was unnecessary. Too much money for what you get.

 

I changed my mind dude, instead of a B model make mine a 3408....

I only drove one Cummins in recent years and it was a Signature 600, darn thing pulled like a freight train.....she had some grunt !!

 

I've heard that before from drivers I'd love to know what Cat makes world wide off just dirt movers...then figure in marine motors and generators, certainly more $$$ than most of us will ever know !!