Peterbilt Dump Truck Conversion

dieseldog5.9 said:

I vote black.

States have different weight regulations when it comes to straight trucks, in our area for instance trucks in Massachusetts running 1200x24 rubber on 58 rears and 20 fronts can gross around 80k on a 10 wheeler, in nh we wouldnt get away with that without a tag axle.

And that truck in mass will be a Mack 300 hp 6speed

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Mass>> 55,000 on 10 and 77,000 on a tri of course there isn't a bridge left in the state that does not need repair. We re-sleeved a mack about three years ago to the back of the cab. The frame gave up again about a month ago stripped the frame again re-sleeved it again to the back of the cab. However the trucks get left out on jobsites where they are usually thought to be a sister ship of a 769.
I really dislike 24 ton boxes they are a pain to spread with in anything less then optimal conditions, they beat the day lights out of the truck. we have one that is older and triple framed and the rail flanges are opening like tulips it will be another victim for the frame guys soon. However hauling giant loads is a New England thing. Beat the beejeebus out of the highway, the truck and the jobsite grade. Cut about 2 feet out of that box put a 3x8 side board up there and the truck will last forever hauling 14 to 16 yds

While I am on my soap box... let's talk about 12,000 pound axles in dump trucks. Way to light... it may haul it for a while or it may fail tomorrow. If you load your new highway truck triaxle to a Mass load of 77,000 and you blow up the drop coming on to a job or you forget to put it down going to the dump... how much weight do you have up there now? As the axle gives up and you wipe someone in a oncoming vehicle. You will be answering a question from a prosecuting attorney that will go something like this; Mr. So and so how is it you were operating a vehicle that had a front axle rated for 12,000 pounds on a public way that investigators calculate that at the time of the collision was carrying in excess of 22,000 pounds and resulted in a fatality. If you are going to build a dump truck... build one that won't get you sued or worse land you in prison.

I own a part of that soap box
Saw all too many Dayton Four spring
Freightliner spring suspension and Reyco set ups on old day cab road tractors used as dump trucks
Are ok for 12 yarders but they put 14 & 18s on them against a 12 or 14k front.
Old Macks Paystar cornqueens Acars and Brockways with rubber block hendrickson 18 or 20k fronts and steerable air pushers best for the money.
Can get Petes Freightliners KWs almost any chassis set up that way and a damn sight better for work

https://www.mass.gov/service-details/commercial-truck-regulations , Shows 3 axle truck at 73000 LBS, assuming thats why trucks like above exist, saw a number of this set up for sale when i was shopping for a dump truck but figured 58 rears would be heavy for nh 56k limit on ten wheelers.

Nothing wrong with a little overkill oversized!!

Honestly i was concerned purchasing replacement 1200 24 rubber.

dieseldog5.9 said:

Honestly i was concerned purchasing replacement 1200 24 rubber.

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dieseldog5.9 said:

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dieseldog5.9 said:

https://www.mass.gov/service-details/commercial-truck-regulations , Shows 3 axle truck at 73000 LBS, assuming thats why trucks like above exist, saw a number of this set up for sale when i was shopping for a dump truck but figured 58 rears would be heavy for nh 56k limit on ten wheelers.

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I am sure the ACar has enough gross vehicle weight to qualify for 3 axle max. Most three axle trucks rattling around here won't

See this attachment 8.05: Approval or Disapproval of Overweight Reducible Load Permit Applications (1) Reducible Load. Reducible load permits may be granted to allow the operation of a motor vehicle together with its load for gross weights up to 73,000 pounds for vehicles having three axles, 87,000 pounds for vehicles having four axles, and 99,000 pounds for vehicles having five or more axles. Triaxle vehicles will be considered as a special type of vehicle and will be given permits for 73,000 pounds if they meet the minimum distance from front axle centerline to rear axle centerline as provided in 700 CMR 8.13: Attachment B: Standard Permit Parameters Reducible Loads. The Department will grant permits to these vehicles for an additional 1,000 pounds, up to a maximum of 77,000 pounds for a triaxle vehicle measuring 19'6" or greater in accordance with the following schedule: 15'4" to 16'5", 73,000 pounds; 16'6" to 17'5", 74,000 pounds; 17'6" to 18'5", 75,000 pounds; 18'6" to 19'5", 76,000 pounds; 19'6" and up, 77,000 pounds. When the vehicle is carrying a permit load the movable axle must be fully engaged. Permits will only authorize travel on specifically designated state highways or ways determined by the Department to be through routes which have bridges, structures and pavements of a capacity sufficient to indicate that they will be able to safely support vehicles of these weights on the aforesaid number of axles. These specifically designated ways are enumerated in 700 CMR 8.12: Attachment A: List of Massachusetts Department of Transportation State Highways. These permits for travel over the designated ways do not under any circumstances allow travel over bridges which are posted for a weight which is less than the gross vehicle weight together with load which is then being carried. No permit will be granted for a weight in excess of the weight for which said motor vehicle, trailer, semi trailer or semi trailer unit is registered or in excess of its gross vehicle weight rating.

Christian Mello said:

Great job on the truck. I'm about finishing up a tractor to triaxle conversion. I have a question about your hinge plate, did you weld that to the frame or just weld it to the inserts and bolt it on? Also how has the 12k front springs held up? Thanks Christian

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Sorry, i know this reply is way behind.. The hinge plate is coped inside the frame and welded fully. The 12k springs are holding up fine. The truck does squat just a tad bit if an operator loads it too heavy. This truck is strictly for my business in excavation & land clearing. The bigger body has its pros and cons. If I could’ve found a slightly smaller one at the time I would’ve went that route. Overall we’ve been very pleased with the truck. Still a lot more to do, but zero issues since the build.

Sorry I didn’t give a final update guys. Still a bunch of things to do with it, but it’s a very reliable truck. I have a very good driver who doesn’t abuse it, and keeps a real close eye on the truck. Most all dumps in my area are conversions, the only complaints I’ve heard on those are the ones with air bags, or aren’t spec’d right. If I can help anyone through there own build, don’t hesitate to ask. Enjoyed the project.