12.7 vs 14l

14.0 after 03 have egr. The engine lifespan is about 400k-700k miles. My cousin's 05 columbia had power loss due to egr. My friend has 06 coronado with bad rebuilt in 800k miles. Had 3 mpg. Place egr shut down sensor and got 5 mpg. We're not allowed to talk about emission delete. 12.7 detroits are the best ever. Known for less power but gets great mpg. it's before 03. 12.7 after 04 have egr and spec to 445 hp.

 

I have a 2005 14l with egr, and it has a stupid amount of power. It has just about 990,000 miles on it, and it shakes and smokes a bit, but it seems like minor issues I haven't tracked down yet. 12.7's supposedly get better fuel mileage, and that isn't hard to imagine since I've been working on mine for close to a year and have gotten the mpg up from 5.5mpg to about 6.5mpg, and broke 7mpg for the first time on my last tank. Know a paper hauler that swears by the 14l and gets 7-8mpg in all three of his Columbias.

 

You can get a 14L without the EGR as I recently saw a post on here about that. Ask your dealer about it.

KH

 

My last prairie run was 1300 miles round trip 8.2 mpg, bobtailing is usually 9.5-9.8 mpg, I'm a big CAT fan, I was a little reluctant to buy a Detroit 12.7 or any Detroit but it's made me a believer, it's a nice engine pulls well, runs well. It's not a 3406E but it's way better on fuel.

 

Me and dad had 12.7 detroit for our century. The truck itself had a custom interior that dad and i worked on. We had 6-7 mpg going 70 mph. Had 3.42 rear diffs and low pro 24.5.

 

The 14L is identical in every way to the 12.7 except combustion chamber displacement, and that was accomplished with a longer stroke crankshaft. All of the engines are great, but do require attention to proper periodic maintenance. Running the overheads on a regular basis is essential, as the valve lash tightens up too much over time. One can go longer, but the average length of time that one should consider replacing the bull gear on the front is around 800,000 miles. And the crankshaft damper should be replaced at 500,000 miles. Both of these mentioned in the Detroit owners manual, which for some reason, few people seem to open. You pay attention to things like this, and operate it properly, there is no reason a Series 60 should not be a well over 1 million mile engine.

I have to admit that the factory rebuilt 12.7 I have in my glider is just about one of the best engines I have ever had. The top contender was a Cummins n-14 in a '96 FLD I used in the past. But this 12.7 is doing a good job of trying to the take the top spot in my experience. Some of the best oil samples I have ever seen from a heavy diesel engine, and darn good fuel mileage results. Here is a couple of screen shots from the Qualcomm which reads the ECM. Actual mpg is roughly .5 less, but you see if even that is not good. And this was done hauling some buik commodity loads like rolled oats, powdered eggs, steel castings, and some steel coils. Of course, with a few lighter loads thrown in the mix. A good average of around 35,000 lb in the dry box.....n From a 515hp 1850 torque set engine. A little higher than the stock factory settings.

 

I have always loved the 470 12.7 Detroit one of the best engines ever made IMO

 

there both good but the 14 liter will pull with a cat even in the big hills