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1999 C7500 Dump Truck Towing Capacity

Jmiller26b ยท 2020-11-29 11:56

I am looking to get into forestry mulching/clearing and am weighing my options. The total weight of my equipment will be around 18k pounds and my gooseneck or pintle hitch trailer (depending on the route I take) will be around 7k pounds. The total weight comes out to around 25k pounds. I was searching for a 2008-2018 Chevy/GMC 3500HD dually but noticed that the towing capacity falls short of this mark. I know the new 2019 or 2020 models are supposed to have 30k+ towing capacity but I don't want to spend that much. I found a 1999 GMC C7500 7.4L gas engine with a 12' dump bed on it for $6000 that runs perfect with 100k miles on it and comes with another whole truck just like it for parts and two snowplows as well and was wondering if I could get a pintle hitch trailer to tow this 25k pound load behind the dump truck. I have searched the internet up and down but have not found a towing capacity number for it. Does anyone have an idea of what it might be? Also, I have never had a dump truck before but this seems like a really good deal. What do you guys think?

Replies28
  1. #1mowingman2020-11-29 12:20

    Do you really need a dump truck, or would a plain old flatbed do the job. Insurance on the dump will be a lot higher than you think. With a flatbed you could install a fuel tank and tool boxes for tools and parts. You will need lots of tools and parts when in the forestry mulching business. Constant maintenance and repairs will be required. Sorry, can not answer your towing question directly. I did have a 1996 Chevy flatbed to tow a tandem dual loaded with firewood. However, my truck had a small Cat diesel and a 10 speed. The whole rig loaded, weighed 45,000. Not sure your gasser could handle that.

  2. #2mitch5042020-11-29 14:05

    Not going to run with traffic from light to light, but it's only recently that anybody thought a loaded truck should. I pulled a backhoe several hundred thousand miles with an IH 1700 with a MV404 gasser and 5+2. It'll be a lot safer than pulling it with a pickup!

  3. #3redneckracin2020-11-29 17:10

    I currently have a 2001 international 4700 with a 275hp dt530e and a 6 speed Allison. I have pulled 20k with it no problem and I don't imagine 24k would be any worse. That being said, I wasn't going to win any races with it but I wouldn't worry about driving it day in and day out.

  4. #4Andy1845c2020-11-29 22:50

    Truer words have rarely been spoken. Sames goes for a semi with enough horses and tall enough gears to do 100 fully loaded....

  5. #5Steve Frazier2020-11-29 23:33

    I did a quick search on Google and found the GCVW for the C7500 is 35,000 pounds.

  6. #6heymccall2020-11-30 00:18

    My 97 C7500 dump trucks with diesel, one auto, one manual, drag around my 40dla trailer, at up to 46k #. Trucks are 33k gvw. They ain't happy towing more than 25k#, but they do it quite often. I can only imagine how poorly the gasser will do.

  7. #7DMiller2020-11-30 05:51

    Be less happy with fuel economy on the gasser than diesel. Diesel is more expensive but buying less equals out over wear and tear on the gas engine.

  8. #8NepeanGC2020-11-30 11:04

    I was regularly grossing 35-40k with my International 4300 and its 195hp dt466 with a 6 speed. Wasn't fast, but it did the job. I can't imagine that a C7500 would have much trouble pulling a 25k trailer. Probably wont be fast. Will likely drink gas, but if it's cheap enough, who cares. The savings compared to buying a diesel will pay your fuel bill for a while.

  9. #9mitch5042020-11-30 12:24

    I am old enough to remember my daddy having tractor-trailers with gas engines, (turboed 534 fords?). The IH 1700 with the MV404 he bought brand new in 1977, but he couldn't get gas tractors anymore so had to buy his Transtars with Cummins. In the '90s I bought an IH 2375 with an L10 to run with the 1700, and he knew I was going to hate it. The 1700 had a 75 gallon fuel tank, and wouldn't spread all day, the 2375 would spread all day on 25 gallons. I have a GMC 7500 with a 3208, and while it is no powerhouse, I wouldn't hesitate to pull 30,000 with it, just slowly. For what you are doing, just moving from job to job, I wouldn't hesitate to use the gas 7500, for hauling all day, the fuel and maintenance costs would eat your lunch.

  10. #10mitch5042020-11-30 12:27

    Surely that was a typo, and supposed to be max gvWr, my 7500 gvwr is 32,000lbs. that would only leave me 3000lbs for the trailer.

  11. #11Willie B2020-11-30 13:04

    My avatar shows my old truck. Mine was 1976 Chevy C6500 27500 GVWR 427 gas truck motor was a monster! It towed 24000 well but NOT fast. Fuel economy was dismal! The replacement truck is a former fire truck 90 Top Kick GMC with 10.4 Liter Caterpillar V8, and Allison auto trans. My dump body is flat with removable sideboards. I'm not as familiar with the newer 7.4. The 454 from 1990 vintage was a very different engine than the 427 truck engine. It lacked numerous features the truck engine had. Notably the forged crankshaft, bigger bearings, and better cooling system. I don't know if you will haul far, on hills, or flat, but I'd avoid a gas engine on a truck that heavy. Perhaps southern as you are, it won't factor. Mine had a doubled frame. Winter road salt gets between the layers of frame & can't be removed. Corrosion becomes severe! The term is rust jacking. The layers push away from each other. My newer truck is a heavier single layer. All the riveted on brackets & crossmembers were removed, and moved to shorten the frame. We buttered between layers with Texaco Compound L Rustproofing Grease.

  12. #12Willie B2020-11-30 19:04

    A friend researched the question: He believes a point comes where it's more about rear axle weight than Gross Combined weight. A truck with 18000 LB rear axle weight rating needs to limit scale weight to 18000 over the rear axle. Furthermore, the pintle load must not exceed its rating. I'm not sure if I get it. Some claim you must register the truck for combined weight. My 28000 GVWR truck towing a 24000 LB trailer with load must be registered for total weight. I'm not sure I believe that one.

  13. #13DMiller2020-11-30 20:16

    May want to call your DMV In the states I have lived in the truck license must cover the full combination truck and trailer and load weight My own Ford super duty is licensed 24,000bl (Beyond Local)in MO just for that reason

  14. #14Truck Shop2020-11-30 20:57

    200,000 lbs. net.

  15. #15crane operator2020-11-30 21:33

    Wouldn't he need the two speed rear end for that?

  16. #16petepilot2020-11-30 21:51

    nah

  17. #17petepilot2020-11-30 22:00

    6x4x3+2 might work

  18. #18Steve Frazier2020-11-30 22:14

    If it's a typo, it was a typo on the page I found with 7500 specs. Had me scratching my head too.

  19. #19petepilot2020-11-30 22:28

    gvwr is what the truck its self is sold as being capable of handling . gcwr is what you license it for to be legal for the gross weight you want to haul

  20. #20DMiller2020-12-01 06:30

    Yes, a separate Number.

  21. #21crane operator2020-12-01 18:02

    Does that come with a copilot to handle the sticks?

  22. #22petepilot2020-12-01 18:47

    only if you are left handed

  23. #23Willie B2020-12-01 18:52

    A gas engine falls weak on torque. It needs gear reduction to power a heavy truck. I found mine had 5 X 2 rear gearing. Up, or down hill I was never very high in gear ratio. The engine screamed 3000 - 4000 RPM all the way. This is not good for fuel economy, and a lesser engine won't survive it long. The GM truck engines 366 & 427 were built to haul. Massive crankshafts were forged from steel, not of cast iron. the cooling systems were high volume, big ports, big pumps, dual thermostats, and VERY big radiators! Cylinders were tall, as were pistons, and an extra oil control ring was equipped. I could brag all day about these engines........until we discuss fuel economy. I fear newer engines were not engineered for the same level of longevity.

  24. #24Steve Frazier2020-12-01 21:30

    I'm familiar with what GCWR is and that's the search term I used. GCWR is often listed in sales literature as a selling point. The page I referenced was a review of the truck back when it was new and that was the information they listed. The laws regarding that number seem to vary from state to state, in NY if you were involved in an accident over the manufacturer's recommended limits you'll have a lot of explaining to do in the courts and very unlikely to come out with much more than the clothes on your back.

  25. #25DMiller2020-12-02 06:10

    This information is what the state level DOT personnel are currently using to get at the NON CDL considered commercial drivers for landscapers, for hot shot services, for short run shippers that use no DOT information as try to slide under the wire.

  26. #26Willie B2020-12-02 07:25

    I've always wondered about where I'd stand in a truck check. Never found any published GCVWR on either GM medium duty I have owned. I have carried 30 750-800 LB concrete blocks plus a 1500 LB boat many times for the antique tractor pulls. With trailer that is 30,000. Add the 12500 truck, that's 42500 combined weight shared between trailer & truck. This load mostly North / South on reasonably level Route 7. It did struggle on even gentle grades with the 427 Gas. As for keeping it under control, no problem. Just a guess, these trucks are fitted with a great variety of bodies. They outfit them with a wide variety of suspension, and drivetrains Owners manual for the 1976 C6500 mentioned tandem axles as a option. GVW varies all over the place. In an earlier year, each state had different laws. Each truck will have a different tow rating.

  27. #27DMiller2020-12-02 12:32

    Current mfg build sheets include GCWR on them, not hard to dig up the old GCW lists as found with the DOT boys here. They were in the old Owners manuals as to the numbers and had to have Final Completion company (Body Installers)sign offs.

  28. #28Jmiller26b2020-12-02 20:54

    You guys are awesome and are a wealth of knowledge! Thank you all for your responses! After reading your comments I think I may pass on the truck and look to go with a newer diesel instead...even though it seemed like a good buy. The fuel economy with the diesel would be a plus because I plan on loading the bed full of logs and hauling them off of the job as well.