Cummins 5.9 or Cat 3126E

[Koa Man]

I am seriously thinking of buying a 2004 F650 with either a Cummins 5. 9ISB 260hp or CAT 3126E 300hp. The truck will be ordered with a 7 spd manual transmission. I basically need to know if the CAT engine is reliable and easy to maintain. I need as much hp and torque as I can get without EGT problems. I wish Ford would offer the C series Cummins in that truck. Which engine should I order?

 

[EMD Diesel Power]

Depends on whether you want to spend bucks for CAT parts. Cummins is pretty reasonable.



Another thing to look at is availability of quality service. I see you are out yonder in the wide blue Pacific. Do you have dealers for servicing either make? with good techs? and priced reasonable?



I drive GMC t6500s with the CAT 3126s in em, (6 spd manuals) and Im impressed with the flatland capability. Not too impressed with the hill-climbing though (full load 22-23k). Haven't heard of engine problems with the fleet. My main beef is the transmissions (due to the tilt cab... been having linkage failures)



Id place my bets with the Cummins. Maybe other guys will post of their experiences here.



Jeff

 

[Koa Man]

I know we have a Cummins Hawaii parts and service center. Never used their mechanics, just bought some gaskets. I can do a lot of the maintenance work on Cummins, never worked on a CAT. The CAT engine is offered with quite a bit more power and I did not want to turn up the engine till after the warranty period, that would be 2007! . Maybe I should just opt for less power for a while and get a engine I am more familiar with. The Ford dealer here only has F650s with CAT engines. I would need to order one with a Cummins.

 

[Evan A. Beck]

Go price out a set of stock injectors for that 3126. I think it may frighten you.



The 3126 has good power and runs smooth, but repairs are $$$$$$. Good luck getting more that 200K out of it. Plus, in the 300/330 HP version, they run hot. I have seen 1,350°F EGT in the manifold on STOCK trucks... Yikes.



Get the ISB, its much more fun. When set up right, it'll outpull the 3126.



One more thing... . You may want to consider spending a bit more and getting a better truck. Something like a Peterbilt 330 or a Kenworth T300. They are much heavier-duty and user friendly. Meduim duty trucks like the F650/750 and the Internationals are pretty uncomfortable... Just a thought.

 

[Koa Man]

Cummins it is I guess. I'll check out the Peterbilt and Kenworth. Hope they aren't real expensive. I have a budget of $65K for the complete truck and the aluminum chipper body is $15K.

 

[Sticks]

Originally posted by Koa Man

The CAT engine is offered with quite a bit more power and I did not want to turn up the engine till after the warranty period, that would be 2007!

At least with the 5. 9 CTD you can drop a simple box on it (EZ) or a step higher on the injectors, and most likely you won't run into any dealer hassles since the engine will take it, presuming it is electrically operated. If it is a mechanical, chances are that Ford will refer you to the Cummins shop for warranty work, and they will have official parts to bump it up anyway.

 

[Koa Man]

Yeah, and now Evan has got me excited about the Peterbilt which I found is offered with the 8. 3 Cummins and a 9 spd. transmission.

Aluminum cab also. Afraid to find out what the price is. Also checked on specs for the Kenworth, but I like the Peterbilt engine and trans options better.

 

[R.E. Miller]

FWIW, I had to do an engine pull on a T-300 KW with a 8. 3L in it. What a pain, very high quality truck from a driver's stand point, but junk to work on.



Russell

 

[RJRobb]

When looking at the Cummins ISB or ISC, find out what CPL the engine will have. Some CPLs can be uprated without hard parts (just reprogramming the ECM). If hard parts are required some require fewer components.



example to uprate to 275HP:

An ISB-240 will require injectors, turbo, exhaust manifold, head with valve seats, and reprogramming

An ISB-260 will only require injectors, turbo, reprogramming



Pete and KW have the same parent company and are top of the line.

 

[bmoeller]

Originally posted by RJRobb

Pete and KW have the same parent company and are top of the line.

http://www.paccar.com/

 

[Big_Daddy_T]

While the 5. 9 is bulletproof. I have not heard the same for the 8. 3. Not saying its junk but it may not be up to par with the b series. Any have lots of experience with the Cs?

 

[rkressg]

The ISC is a great engine if you leave it stock. But if you think the ISB has major electronic problems with the fuel pump, the ISC is way worse. The fuel pumps are so bad, that Cummins dealers now carry replacement electronic parts for their fuel pumps. The internals are good quality for a medium duty diesel, though the engine is heavy and long a medium duty chassis.

 

[Koa Man]

Is the B engine capable of pulling a GCVW of 34K up a 7% hill at 55mph without running hot? Presently, my truck cannot run 55mph pulling a GCVW of 20K up such a hill and keep the EGTs under 1200. Please remember this is a chipper truck with a big headboard... . almost like running your truck with a sheet of plyboard sticking up above the cab. No aerodynamics and the wind drag must be tremendous.



I did not know of those problems with the C engine. I really would like this truck to have an engine with about 400hp and over a 1000 lbs of torque without running hot.

 

[rkressg]

The B engine is used in applicaitons up to 59,900 gvw. Though I would not reccomend this small of an engine for this application. If you are running a chipper, I would go with the larger 3126 or an L or M or if possible X engine. The B is a great engine, but it does not have enough for something like that application.

This is all just in my opnion.

-Rich

 

[Koa Man]

Does anyone know if the M engine is offered in any med. duty truck? Given a choice between the B or C engine, and taking into consideration the necessary tradeoffs between power/reliability/running high EGTs, would I be better off with the B engine in a class 6 or 7 truck?