18 Wheeler Fuel Mileage

[Big P]

Does anybody know what kind of fuel mileage they get when at 80,000 GCWR?

 

[ISBPilot]

MPG

It depends alot on if the rig is company owned and set up for economy or operator owned and set up to "haul the mail", but somewhere in the range of 4-8mpg.



Todd

 

[CTabor]

Mine gets 4. 5 to 4. 8 loaded about 5 empty.

 

[rkressg]

All of our old work trucks would get between 4. 3 to 4. 7 mpg. They all were limited to 67 MPH:{ no matter how hard or long you pushed on the loud peddle. Got to love the good ol FreightShaker. :{ :{ :-{} :{

 

[BCFAST]

Great topic!! I find this interresting as well... always regarded Cats as being thirsty. I owned a T600 with a Series 60 motor (370hp/430cruise) and had it converted into a Toter-Home and pulled race cars. Running 70mph @ 65k lbs I regularly got 10+mpg. and nearly 12 empty or light. This was nothing fancy or bombed... just a 9 speed on 22. 5s. Oh, and the motor was an early version (1992) that had only the DDEC I computer stuff in it... I understand that the DDEC III and new are much better.

 

[NVR FNSH]

While in college I went to a presentation by an alumni that worked at Kenworth(I think) and he said that with a bunch of aerodynamic work - fairings, skirts, ball/socket between the cab & trailer, tear drop thingy on the back of the trailer - they were able to get ~10mpg out of a loaded rig. I don't remember if it was loaded to 80k or not.



Brian

 

[Ramafid]

The trucks that I like the best at work are the Mack CH600's. The engines are 728 ci with 355 hp@1800 rpm. Torque is probably around 1300-1400 lbs @1200 rpm. The transmissions are either 9 or 10 speeds. We usually pull 60K-70K lbs and mileage is always 6. 5-7. 5 mpg. I think that's darn good!

 

[Okie-Go]

My uncle who is retired from driving now got between 6-8 on the last truck he drove. A 99 conventional Peterbilt. It was one of those aerodynamic ones. Can't recall engine size or rearend ratio.

 

[E7mack96]

Big rig Economy

I own Mack CL-713 6 axle dumps. We run the 487 hp/1760 tq engine and Mack 13 speeds. 4. 42 rears on 22. 5 rubber. The drivers get 4. 7 -5. 0 mpg. I get 6-8 mpg on same runs. (i have incentive to drive efficiently) These trucks are always loaded to the hilt, and then some (can u say 30,000 lbs overload fines)



I think the trucks run great, and get excellent fuel economy too.

 

[JHansen]

The old Western Star with a 3406B-425 that I used to run averaged around the 5 Canadian MPG mark..... mind you that was pulling 110000 lbs. around and a ton of idle time (pumping time in an average 10 hour day was around 4. 5 hours !). Longer runs on summer fuel probably came in closer to 5. 5-short service-work type runs on winter garbage worse... ...



The T800 KW with 3406E-475 power that replaced it did better-can't remember exactly how much but 3/4 mpg sticks in my mind. That was a good truck-once you learned the difference in the powerband between the electronic and mechanical motors. Great power... ...



Jason

 

[FL70CAT]

4. 5-7 is the most common range.



A big factor is usally if the truck is a boxy classic styled truck or a modern aerodynamic one.

Second large factor is idle time, which greatly drops mileage.



Last time I drove a KW-T2000 with a 460hp-N14 Cummins, I got 6. 6-7. 0mpg



It had a 18spd 2X-od, 3:55's, 24. 5's and was pulling a 48' reefer.

 

[FL70CAT]

The 6. 6-7. 0 varied due to terrain. I started in Pittsburg and ended up in Dallas. I was pulling beer from Latrobe abd was grossing all but 80,000lb. I had to watch how much fuel was added in the tanks when I filled up.

 

[Ray Torresdal]

FUEL MILEAGE

A big variable is trailer type - a livestock trailer pulls much harder than a grain trailer, or tanker - both loaded the same! The fellow I drive part-time for is averaging over 7mpg, pulling grain trailer and only loaded both ways during the spring fertilizer season. T800 KW w/Detroit and 13 speed. Pretty amazing when I think back to my '73 Pete with 1674TA Cat (270 Hp. ), 13 speed, geared right at 70 on 22" Michelins and never saw 6 mpg. (bought the little horse, knowing that I would probably kill myself with a 1693!) Ray

 

[C Schomer]

I had a 68 IHC Fleetstar 549ci V8 gasser 10 wheel dumptruck that got 1. 5 loaded(55-60k) and 3. 0 empty. I had a 59 IHC cabover wrecker 549 gas that would get 10mpg unloaded. Had a 64 IHC conventional semi tractor NTC280 4. 44s RTO 10 speed and 22. 5s. It averaged 5 - 5. 5mpg. Craig

 

[JHansen]

Guess I should have been a little more specific as to truck/trailer type and service! I used to haul crude oil/produced salt water/combination of the 1st two/or when I felt real adventurous condensate around the highways and byways of Alberta. Both the WS and KW were full trucks (body job tanks) with 3 axle tank wagons (single steering axle and rear tandems). Heavy buggers-50200 kg GVW (tick over 110000 lbs) and over 19000 kg (40000 lbs) empty depending on how much mud/snow/ice accumulated over the course of the day. Lots of trips up north when the snow was just melting on the highway, you'd scale out with 3000 kg of crap stuck on the truck. Good thing condy's light!



Like I said before in an average 10 hour day you spent around 4. 5 hours either loading or unloading-and the majority of the time the pickup point was within 45 minutes of the destination. Furthest I ever ran was around 2-3 hours loaded up to Hardisty with condy... . still a ton of starting and stopping though. Depending on the route you took you still never saw a straight driving stretch of over 45 miles... .



The new truck that Dad's driving now averages around 6 Canadian with a 475 Cat in a T800 pulling a tridem tank trailer-but it's a sour sealed trailer (rated to handle 14 psi pressure so it's round like a propane bullet rather than oval like a fueler) so it cuts a ton of wind. Nice truck though-hate the way it looks (kind of a purply-grey color with everything painted (tanks, bumper etc), 1 stack, no air cleaners, low-rise Aerocab) but boy it's sweet to drive. I got to pilot it solo for around 15 miles 1 day-that 72" Aerocab is like driving a motorhome to a guy who ran day cabs his whole career . Air ride cab, 8 bag rear tractor suspension, and air ride trailer----smooth! Almost made me want to start driving again-almost... ...



Jason

 

[Cummins Cowboy]

i saw in an earlier post in this thread and it is probably a stupid question but what is a reefer. I thought this was something that most of us smoked back in high school??LOL but in all seriousness is this a type of trailer???

 

[Ray Torresdal]

reefer

Reefer is a refridgerated van, in addition to whatever you smoked way back when . . .



Ray

 

[SLindblom]

Fuel Mileage

I used to drive a KW T600 with a Cat C-12 set at 435 hp, through a 13 speed. Loaded to 80,000 starting in Rapid City and going over the hills in Wyoming to Las Vegas I would get around 6. The mileage would be around 5. 6 mpg by the time I got to the high point in Wyo, and the rest, being basically all downhill, brought the average up. Of course, the uphill speed was around 35 mph. This is pulling a 53" dry van.

Same truck, grossing half that, got over 8mpg on a trip from Rapid City to Houston and back.



I am now in a Pete 387 (aerodynamic, like a KW T2000) with a C-15 Cat set at 475 and a 10 speed. Lifetime average for the truck (230,000 miles) is 6. 3. at 80,000 gross, I get close to 6 mpg. Here in SD (and the rest of the midwest, including WYo and eastern Co), wind, especially cross winds with a dry van, really eat into the mileage. Worst mileage is around 4. 5, best, with a tailwind is in the mid 7's.



I normally drive at 67-68, company governs truck to 72, so I have 4-5 mph to pass with if I need to.

 

[M Barnett]

All of the newer trucks are electronic, which helped mileage a lot. My 99 Frieghtliner with a 525 HP Cummins will get 6 mpg pulling a tanker at 85,000 lbs.

M Barnett

 

[speedracer]

tons of variables

There are tons of variables, aero vs classic styling, engine hp, gearing, road speed(a big one!), wind, etc. I get 5-7 mpg depending on load, tail or headwind, winter or summer blend fuel. I don't pull heavy very often(gotta love that light freight), but grossing 80k vs 40-50k seems to cost about 3/4 to 1 mpg. I also think the ever tightening emissions standards cost mpg. My last truck was spec'd almost identically but got about . 5 better mileage. However, it was a 95 vs '00 for the new one. I've heard the emissions standard that came out in 98 hurt mileage, and it seems to be true in my case.