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Freightliner FL50/60 fuel economy

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Fuel Is Goin' Up $$$$$

BD turboguard - good setting? how does it work?

What kind of fuel mileage would a person expect to see in a Freightliner FL50 or FL60 low pro with a Caterpillar 3126-190HP in front of a 6 speed manual... running empty on the highway? I've been looking to buy a used cab chassis and install a 9' or 10' light duty dump bed on it.



I'm going to make a guess at 10 MPG.
 
We had 3 FL70's single axle trucks on 11R22. 5 rubber with the exact powertrain that you are looking at for parts delivery previous to our replacing them with Mercedes Powered M2's.



All three were equipped with 22' van bodys so wind resistance was right up there.



I drove one of them 3 days a week back in the day and I used to get a solid 9mpg no matter what on secondary, hilly roads in the winter. You should be able to knock 10 mpg out of one with a dump on it if the gear ratio works out.



How many miles on it and has it ever been overhauled????



Mike. :)
 
I think that figure is very doable. I had a 2002 IH 4300 with a Holmes steel rolloff body on it, weighed 14,700 empty. It had the 195HP DT466, Allison 2400, 4. 33 gears and 19. 5 tires. It would do just under 12, hand calculated at 65-70 MPH with a little PTO time in there also. At 55, the instantaneous readoud would show 14-15 MPG.
 
The mileage on the truck is 148,000 with no rebuilds. Its a very clean unit that used to have a standard box body on it for delivering medical supplies to hospitals in a given region. No rust anywhere, spring suspension, like new interior... very clean truck. The one I'm looking at is an FL60 with lo-pro tires, hydraulic disk brakes, 6speed manual, and all service records... which show no issues.



The dump bed I'm looking at is a new Henderson contractor type dump. Its more like a flatbed with 12" sides... so it won't be very heavy. It'll have an under body scissor type hoist so I'll also be getting the pto pump, controls etc etc.



For the money... I can get into one of these just as cheap as a nice used 1 ton diesel dually... maybe even less. Seems like they give these things away once they are out of a fleet. Just gotta find a nice one. I've seen several nice Internationals as well. Some auto, some manual.



I've been wanting a one ton dump for a long time to pull a trailer for a skidsteer and to just do general hauling work. Might as well get something this sized and still be under CDL requirements.
 
Also... seems that some say get the Cummins ISB5. 9 version... as the Cat's have been known to melt down and cost a small randsom to rebuild.
 
Also... seems that some say get the Cummins ISB5. 9 version... as the Cat's have been known to melt down and cost a small randsom to rebuild.



I agree or get one of the Internationals with a DT466. The DT466 has replacable wet cylinder liners and is less expensive to overhaul in-frame compared to the parent bore engines.



Bill
 
The mileage on the truck is 148,000 with no rebuilds. Its a very clean unit that used to have a standard box body on it for delivering medical supplies to hospitals in a given region. No rust anywhere, spring suspension, like new interior... very clean truck. The one I'm looking at is an FL60 with lo-pro tires, hydraulic disk brakes, 6speed manual, and all service records... which show no issues.

The dump bed I'm looking at is a new Henderson contractor type dump. Its more like a flatbed with 12" sides... so it won't be very heavy. It'll have an under body scissor type hoist so I'll also be getting the pto pump, controls etc etc.

For the money... I can get into one of these just as cheap as a nice used 1 ton diesel dually... maybe even less. Seems like they give these things away once they are out of a fleet. Just gotta find a nice one. I've seen several nice Internationals as well. Some auto, some manual.

I've been wanting a one ton dump for a long time to pull a trailer for a skidsteer and to just do general hauling work. Might as well get something this sized and still be under CDL requirements.

I think you WILL need a CDL. When you add the GVWR or actual weight of the truck and trailer you mentioned above and the fact that it will be used in a commercial activity it will exceed CDL threshhold.
 
I want to be honest here with you and share what I have witnessed with the 3126 Cat Powered trucks that you are looking at.



As mentioned above, the Cat 3126 is a good little engine but when they have issues with the HUEI system it can be a nightmare. When ours got up into the 200,000 mile + category it began.

The issue with all three, one in particular was a random skip that no one could pin down. It was the worst after a 2 or 3 hour drive at speed, when you stopped for a light it would almost stall, then skip. We fooled and fooled with it, threw a pile of various parts at it, my top Cat Tech threw up his hands.

Sent to the local Cat distributor where they fooled with it for a week and then they gave up.

We left it alone and put up with it until we pulled it out of service when the new trucks arrived. It still ran great at speed but the skip at idle would drive you nuts.



Also didn't look to good delivering parts in a skipping Freightliner if you know what I mean..... :-laf



The other 2 were doing it but not as bad.

We even did the lower end on the worst one thinking that the slight reduction in oil pressure due to wear of the bearings and other components affected the HUEI system in a hot idle, low load condition. It helped a little but did not cure it.



I would seek out a 5. 9L or as Bill suggests a DT466 in a Navistar. Much tougher and reliable engines for poor folks such as you and I. :)

Just remember with a 5. 9 the same rules apply to the fuel system, if it has a VP-44 you gotta' keep the transfer pump working. There is a software update and kit that will turn the Check Engine light on in the event of a transfer pump failure, that would be tops on my list of stuff to have done first.



The FL series cab is great, very tough. They have a few small issues but nothing to worry about.

Good visibility, easy entry and exit, heat and A/C system is a tad small.

Where you are looking at a Non-CDL truck with Hydraulic Brakes give the rotors and calipers a good look.



I personally would find one with air brakes, much cheaper to maintain and better brakes to boot if you have the air brake endorsement on your license.

Plus that gives you onboard air for other projects. Also gives you Maxi-Brakes for parking rather than the problem prone cable operated drum style parking brake that hydraulic trucks have, have also seen some Fords with a hydraulic style Maxi-Brake. Works OK but parts are expensive.

Also consider air ride, a lot easier on your back and the truck. There are also trucks around that have air compressors, air ride and still have hydraulic brakes for Non-CDL applications.



Try to avoid the automatics, a Fuller six speed will do it better and cheaper to repair.



Check clutch condition as they tend to have a higher speed reverse and some drivers don't understand you need to engage and disengage clutch completely when backing into a dock, not slip it the whole time. Had one driver here that needed a clutch adjustment about every two weeks, could not back up without slipping the dickens out of that poor clutch. . :mad:



If you do purchase a Freightliner product and have any questions, please ask away. I see there is a new member that works at a FTL dealership in New York also so between the two of us we can help you.



Don't wish to confuse you, only want to see you get something that you will be happy with and enjoy.



Mike. :)
 
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My suggestion is to stay away from Cat. I would even recommend the DT466 over the 5. 9. They have a great track record, and as mentioned, a wet sleeve design, so when it does require a rebuild, it can be done in frame. Also, parts are inexpensive and you can practically go anywhere for parts availability.
We've had several DT466s in our fleets and they are great motors. In fact, when we start rotating our fleet out, they will all be MaxForce 9s with Allison automatics. MaxForce 9s are 570 ci DT466 motors.
Our cat 3126 motor has had the head off 3x's, (twice by Cat dealer) and still can't figure out what's wrong with it, on it's second turbo, and still pukes antifreeze daily. That truck has roughly 190,000 miles. Our other motors (Detroit Diesel, Cummins, DTs) all have at least 4 times the miles with almost zero problems.
Just never been a fan of Cat...
 
If 26000 or below and no air... then a CDL is not required. If the trailer is below 10000 rating and being towed by an "non-CDL" vehicle... no CDL. And its not for commercial purposes... personal use for land I own and where I want to build a barn/house.



No way in hell I'd ever get into dirt work excavation and hauling for "money". I'm around this stuff at work all day for 15 years... and know what its all about. What happens is, every family member and friend wants to use your stuff or have you do some job for them every weekend, all summer... . for free. And paying customers never want to pay what its worth to do a job. They think you should drive 20 miles to pick up a load of rock for them and pay you $20 plus the cost of the stone. I'm gonna hide this stuff... and tell nobody. :)



Anyhow... the International is sounding very good to me. I'm going to redirect my search.
 
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Any parent bore engine will be a bit challenging when its time overhaul it, Cat parts are usually more available then international, dont be worried about the mileage, we have over 300 service trucks all equipped with 3126 engines some with over 330,000 miles, never been overhauled, yes the huei fuel system is a bit pricy when it fails, wether it cat , cummins or international they all have or had problems, the dealer makes the difference, theres good and not so good out there, Cat and International are in bed now with the new Cat Vocational truck, should be out in the later part of april, should get interesting.

Regards Rich
 
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