And now for another round of: could you/would you/should you

[Ascinder]

Hi, I have a 1988 C7000 and I am trying to figure out what it's capacity would be to pull down the road. I have driven trucks for UPS Internationals, Sterlings, and a couple Macks. We would haul double 28s, 40's and 53s over Donner summit in winter in the sierras all the time with single screw trucks. I have also run triples across Nevada and Utah(so pretty flat, but windy) This C7000 doesn't seem that far off, but I don't know that much about calculating what a truck is capable of because all that was done for us for the most part. The specs of the C7000 are maxed out for weight and power. It has the 10.4L 3208T(low miles), a 12K front axle and a 23K rear with 4K aux springs and air brakes all around. I would like to be able to pull an excavator and am curious to know what weight I should be looking at. I would like to be able to pull a Cat 215, and would love to pull a 225, but I think they may be beyond what the 7000 will do-just not sure. Also, I am anticipating that it will be (even more) gutless on passes. I know our Sterlings used to bog down to 35 or so going up Donner. It is going to be used only a handful of times for longer distances, but probably a bit more for local trips.

 

[AzIron]

in my humble opinion you wont have any problems with the 215 on flat ground the problem with the 225 is weight you would need a 30 ton trailer or better and with the machine weight around 50 thousand pounds you will be over weight on your drive axle unless you use a three axle trailer but you will be pushing 80 thousand gross. personally i would not try to pull that size machine with a single screw and in my experience your truck will be under powered to pull that at any speed especially on a hill. the 215 wont be a problem weight wise and if your not in a hurry it will pull a hill but not very fast. that truck with the engine it has is not really intended to pull more than 60 thousand pounds especially out west were you can see upwards of 6 percent grades for more than 3 miles it will build heat and you will have to slow down. it will get the job done but you will have to drive it right.

 

[lantraxco]

In Oregon with typical 10.00 front tires, you would max out legally at 30K solo, 20 on a single drive axle with duals, thousand pounds per inch of tread on the steers. In my opinion even a 215 is too heavy to be pulling behind a medium duty truck like that. I pulled a lot of machines behind a full sized KW cabover with a 335 Cummins, 10 speed, and a single rear axle that would have pulled the Titanic, it was that big, probably a 30K. Had a Miller tilt deck, you had to put 10K on the fifth wheel and 34K on the trailer tandems to be at legal gross, we often pushed that some. Really needed a 13 speed and especially a jake brake, those little 12" drums on the trailer axles tended to turn brake shoes into bacon rinds. Ask me how I know... Pulling a lowboy you would have better brakes but more trailer weight and more weight on the fifth wheel. Technically it may be legal and doable, but I wouldn't.

By the way, there should be a data plate with the GVW and GCVWR stamped in it, Gross Combined Vehicle Weigh Rating is all you can legally haul in any combination according to some weighmasters.

 

[Willie B]

That scares the stuffing out of me. I have a 1976 C65. Mine gives on the nameplate only front (10,000), rear (20,000) and GVWR as 27500. Mine has gas 427. I tow a triaxle 9 ton, with the heaviest load a (16500) backhoe. Truck has air and stops on a dime. The trailer has electric brakes and they work OK. I've had a few steep hills where I run low on power in the lowest gear. I'm not sure what I'd do if it did stall out on a too steep hill.

Willie

 

[lantraxco]

That scares the stuffing out of me. I have a 1976 C65. Mine gives on the nameplate only front (10,000), rear (20,000) and GVWR as 27500. Mine has gas 427. I tow a triaxle 9 ton, with the heaviest load a (16500) backhoe. Truck has air and stops on a dime. The trailer has electric brakes and they work OK. I've had a few steep hills where I run low on power in the lowest gear. I'm not sure what I'd do if it did stall out on a too steep hill.

Willie

You stay in it, pray the brakes hold (most electric brakes don't work well, if at all going backwards) and call for a big tow truck. Or somebody to offload the backhoe. That's what always scared me about running low on power, or traction, coming down backwards if the brakes didn't hold and running off the road.

Interesting that the GVWR on your truck is less than the combined axle ratings.

 

[Ascinder]

Thanks so much guys. This is the exact kind of info I was looking for. So when I am talking about transporting this, it would be under ideal conditions, brand new brakes, with no timetable, and a very flexible route meaning I could avoid the worst passes and grades. Looking at the build of my old UPS semis and mine, they seem pretty close, although the Navistar's would certainly beat me power wise. Transmissions are the same(Roadranger 10 sp). It sounds like the 215 would certainly be the safer bet, but with proper planning and a suitable trailer the 225 could be considered, but may be pushing it a bit too much. My truck is a bit weird in that it was "reconstructed" into a pickup, and therefore the data plate listing the GVWR was removed and some California ID plate put in it's place. I am getting the numbers and specs off of the RPO codes that were in the glovebox. In my state(NV) when you go to register a vehicle, you literally just quote them whatever GVWR you want at either the regular DMV or Commercial DMV. If I claim my truck weighs 1 pound, they're cool with that. If I claim it weighs 1,000,000 pounds they're cool with that too. Doubt other states would see it that way. I don't know how much of a pain in the ass it would be to get is relabeled with it's proper rating, but I bet it is a "manufacturer" thing only.

In Oregon with typical 10.00 front tires, you would max out legally at 30K solo, 20 on a single drive axle with duals, thousand pounds per inch of tread on the steers.

Mine are M124Z 11R24.5's up front and M620ZL 11R24.5's. Not sure how that would affect things, but that's what I have got.

The transmission is an RT-6610 so my gear range is from 1.00 to 8.94 and the rear end looks like it's a 4.33. Not sure what you would be working with on a big truck.

 

[lantraxco]

11.00 tires, you would be good for 22,000 on the front axle here in Oregon, dunno about where you are.

Licensing is irrelevant, same deal here, you can license a vehicle for any weight you want up to 80,000 without any special permits. Weighmasters and the DOT however look at three things, are you over your licensed weight, are you over the legal weight per axle/length/highway restrictions, and are you over the manufacturer's rating for the individual axles and the GCVWR for the power unit. There are of course exceptions....

I have been warned but never ticketed (which I attribute to having a spotless truck and a spotless logbook) for over gross, over axle, over bridge, and over my extended permit (101,500 on that rig, dump truck and transfer). Dump trucks usually get a ton or so leeway (but not always) because they're hauling such variable loads. One day I was a tad over coming over the cascade range down to I-5, convinced a rather jovial (believe it or not) weighmaster that I had gained all that weight because it was raining and I was hauling red lava cinder which is very absorbent. He laughed, told me he hadn't heard that one before and shooed me out of the scalehouse.