Opinions on C-12??

[truck]

Looking at a truck with a C-12 set at 410 with a ten speed and 3.90 rears. It has roughly 650000 on it. Planning on using it to pull a hopper on relatively flat ground. What is the expected life of this engine as it has a good maintenance record?? It was a fleet truck.

Thanks for your opinions.

[GMAN]

It depends on how it was maintained. You could get over a million miles out of it with proper maintenance. The C-12 is the same thing as a 3406 E. One thing I found out about them is that if you ever need to rebuild one of them to go ahead and do the lifters at the same time. According to CAT that is a weak area for that engine. I have one with over 800,000 miles that is still going strong. Another was rebuilt with about 900,000 on the engine. I don't know about the average rebuild for a CAT, but it is around 750,000 miles on a Detroit series 60. I would expect to be getting close to having a rebuild once the engine gets around 700,000 miles on it. I have met a couple of owners who have gotten over 1 million miles before an overhaul. One guy I spoke with had 1.2 million miles on his without having to do any engine work. At the time he was having injector sleeves put in the engine. Other than that, he said the engine was still running strong.

[Kranky]

Someone asked the same question a while back and here is my reply:

The Co. I work for has a fleet of tri & quad axle dump trucks with Cat C12 engines.

They have proved to be very reliable & trouble free.

I might add that the company has a maintenance program that is very meticulous with oil & filter changes done on time, every time, and oil analysis.

I work in the shop, and drive them sometimes too, so I see both sides of the picture.

The C12 has good power & driveability too.

BTW, GMan, I believe the C15 is equivalent to the 3406E isn't it?

[GMAN]

Splitshifter, my local CAT dealer is the one who told me about the 3406E and C12 being the same engine. I will try to remember to check on my engine and see if it tells.

[Kranky]

Here's some info I found on the Cat engine website:

http://ohe.cat.com/cda/layout?m=101242&x=7

http://ohe.cat.com/cda/layout?m=85523&x=7

The C12 is 12.0 liter, while the C15 currently @ 15.2 liter, and previously @ 14.6 liter corresponds to the 3406 @ 14.6 liter.

[GMAN]

Thanks for the link, Splitshifter. Both my engines were made prior to 1999. One was made in 1996 and the other in 1998. I believe you are correct about the 14 and 15 liter engine size, but the C15 didn't come out until 1999, according to the link. It does seem odd that the 3406 would be 2 different liter sizes. :?

[Bobby]

It does seem odd that the 3406 would be 2 different liter sizes. :?

Early (1999 to 03) C15 was the same displacement as the 3406E @ 14.6 liters, They both evolved from the 3406 platform. The later C15 w/twin turbos was gaining lots of smog stuff and had more in it's future...07
IMO they increased the displacement to maintain the power levels which are still at about 475HP. They did gain some torque, like they should have with a bigger engine.

The C12/13 is a smaller engine, not as tall as a C15, but much lighter.

Finding good Tec's can even be a challenge at dealers, so I'm not surprised at the info you got.
Both are good engines...if you get a good one...

[GMAN]

Thanks for the info. You are right about finding a good tech.

[heavyhaulerss]

if an engine will last or is a good one is hard to answer. i have a 60 ser detroit 11.1 i have over a mil mi on it. the truck has never broke down. it has never had anything other than normal maintenence done to it. it even has the original clutch in it. it's a 95 model intl. it still gets very good fuel mileage. i swear by my detroit. but the guy who trained me years ago had bought 2 detroits in 6 years both had major engine prob.. some things last for good reason, well taken care of e.t.c. & some have luck i guess. i have always serviced mine but the life i have gotten out is.. i think uncommon.

The C12 is the second gen of the old 3176 series. I know that the 3176 had a few major issues like being pushed to hard for to long it would melt down. I drove for Millis and my 1996 FLD had a 3176 and that one blew up bigger than a top fuel engine that blew a supercharger. Turns out Millis turned the fuel down to make sure that we could not speed but we were overloading the engines. Cat refused to warrenty the motor. The C12 is a decent motor.

[roadranger]

Just FYI I've read that the C13 is based on the C15 (3406e) motor and more reliable than the 3176 based C12 which had problems early on. But I'm sure as in all engines you can get a good one or a bad one - all you can do is take care of it and hope it takes care of you 8) !

[truck]

Thanks to all who replied. The depth of knowledge on this site always amazes me. What a wonderful resource!!

[Mack2]

We have one with 238,000mi and it has already blown a turbo and is always leaking oil.

[Mackman]

We have one with 238,000mi and it has already blown a turbo and is always leaking oil.

Thats funny you said that my oldmans c-12 blown a turbo around 200,000 but it never leaked oil. Now he has a c-15 so far no problems. Other then that the c-12 was agood motor for him.

[Mack2]

We have one with 238,000mi and it has already blown a turbo and is always leaking oil.

Thats funny you said that my oldmans c-12 blown a turbo around 200,000 but it never leaked oil. Now he has a c-15 so far no problems. Other then that the c-12 was agood motor for him.

Yeah they don't know what the deal is with the oil leaks but the do seem to be getting better.