I have 1990 International 4900 dump truck with DT466, air brakes, double frame, spicer 5speed with 2 speed rear, 22k rears, 11k fronts, GWVR 33k. My tag trailer is 20 ton with unladen weight of 9,700 lbs. The million dollar question is what is the heaviest machine I can put on the trailer and not hurt my truck or put myself or other people on the road in a unsafe situation? I have my CDL-A so its not a legality thing just a saftey thing. well and I dont want to kill my 31 year old truck. Input would be great!!!!!!
We run C7500 3116/allison C7500 3116/7 spd manual Pete 325 C7/ 8LL All of them pull my Interstate 40DLA trailer, with up to a Cat 953C (39k # + trailer) on them. Never an issue, BUT, make sure your hitch in the truck is rated for that. When I replaced one of the hitches, I found similar that were rated much lower than what we tow. Never a problem. Our 963B LGP @ 49k # broke the tow hitch on one of the trucks (actually a Mack RD688S) before it ever pulled out. My Mack's use the same hitch.
Does the trailer have electric brakes? If so that is the biggest safety issue. Making sure they are all working and the breakaway switch and battery is in good order.
I'm hoping it's an air brake trailer at 20 tons. I have not seen a 20 ton electric brake trailer. I'm far more conservative and would draw the line at about 15 tons of equipment. that would be 40,000 lb of trailer and equipment, minus up to 6,000 lb of hitch weight. At 6,000 lb of hitch weight that trailer is going to manhandle you in corners. think about the forces driving down into a downhill corner in the slick. You can do it, but you better be familiar with the Johnson handle. The trailer will want to push you into a jackknife, and your relatively light tractor isn't going to resist it very much. That's what I tow with a LN9000 tandem axle dump truck. it gets around pretty good but there are times when that pin weight coming in at an angle can be fun!
Mine is GMC Top Kick 1990, Cat 3208 V8 10.4 liter turbo rated 250 HP, Allison 4 speed trans. Eaton 22000 LB differential is about 4.89:1. Truck is rated 28000 GVWR. I tow a triaxle CAM Superline rated 23000 GVWR. Trailer nameplate claims 3000 LBS empty, I know better. Trailer brakes are electric, truck is air. Current backhoe is Case 580 Super N, I'll estimate 17000 LBS. On Vermont hills, every trip involves up & down hills. Steep hills are a slow process whether up or down. Loaded, the whole rig is 37000 LBS. I would NOT want anything heavier on hills! If truck manufacturers rate trailer tow rating, I haven't seen it. Inspect your truck frame. Two layer frames can weaken with rust.
Mine is a 1960 B75 Mack 400 Cummins, 13spd tandem 280" WB--------It hasn't hauled or moved a damn thing except my own ***.
With a dt 466 your going to overload your motor before you get to full rated weight a powerhouse they are not I have done that setup before a backhoes a pretty good load but food for thought with axels your bridge about 60000lbs truck and trailer probably get between 25000 and 30000lbs so your really only left with about 30000lbs of usable weight If your pulling any hills or anything you will lack horsepower with that setup before brake power if everything is air brakes but them ol dt never seem to die
We need pictures! I've always been terrified of buying an old truck. They are, in every case SO needy. My obsession with owning a truck that won't earn its keep has lead me to fire trucks. I've owned two. In each case, converting a fire truck to a dump truck costs a pretty penny, then I get the pleasure of working all the bugs out. Old fire trucks are low mileage/hours, low on rust, but they suffer all the problems age brings on other trucks. I occasionally see vehicles come from climates less conducive to rust. In all measures of mechanical condition, they are attractive. Maybe I need to travel to shop for trucks.
I cant help you with anything on trucks........but I did sleep at a Holiday Inn Express last night!
I had a father in law, two brother in laws gave lots of unsolicited advice. Dysfunctional people who knew exactly how my life should run. Two died, one is estranged. I now stumble through life making mistakes without them. Do you really think you're ready to fill that role? I got a trouble light on a Case 580 Super N.
As someone who also has a single axle, 33k dump, it is painfully slow with anything around and above 15k on the trailer. It will do it, safely, given the airbrakes. These trucks are slow with 9 ton in them. I have found you will run out of power before anything else (brakes or GCVWR)
Yeah I saw that. From my experience a circle with teeth around it is a transmission symbol, probably some type of pressure issue I would guess.
There is nothing “old” about Truckshop’s Mack...now it’s a beautiful rig.
it has air brakes. my truck is set up to tow a trailer with electric too but my trailer is air brakes
the trip would be 17min and 95% highway. I'm hearing most say that bottom line my truck dosn't have the power and its not really a too much weight on frame or brakes issue but the motor it has in it. dose that sum up the consensus?
What do you want to haul? Power is one thing speed is another. If you are careful you can haul way more than your truck is rated for and never have a problem. Most of my stuff is way under powered for heavy traffic but there are alot of back roads were i can take my time and be safe.
I had an 05 International 4300 with a 15 ton tag. Truck had no problem with 30k trailer, 12k truck. We're pretty flat around here, so take that for what it's worth. At 195hp, it ran out of power long before I considered it 'unsafe'. 40-45k gcw was comfortable. Mine had a 6 speed.
Seth figured out how to read it all. Four codes come up. One is intermittent signal from fuel gauge, others are electrical connection to transmission.
Are you doing it every day or one time deal and what are you hauling You can push that truck and motor a long ways loaded maxed out but you will take about double the time to get there nepean is right that 45000lbs is the sweet spot for that set up it can handle up around 60000lbs but it wont be running speed limits in traffic
Agreed - I had my rig around 50-55k a few times, and although brake and stability wise it was fine, it was slow as can be. I felt like I was burning the motor out of the truck. Never did kill it, but I only put 100k on that truck before I sold it.
Another chance to post this junker.
Yea! That might be able to handle the loads! If you sell it to him let me know when it is heading to NH, I'd offer to buy him dinner when he's passing through Central NY on his way home! How can he pass it up, custom built Mack and free meal!
WOW!
I was at 66,000lbs on trailer 25 ton tag and about 20,000lbs truck with 330hp 6 speed allison, man that was slow, I bumped up to 400hp 13 speed truck is 23000lbs with same trailer and all is good. If it's pretty flat you can get away with a lot of weight if it's once in awhile. Long as the truck is in good working order, running it WOT for a few minutes to get up to speed won't hurt anything.
DAMN that's nice. Needs a coat of fire red paint to be perfect.
The reason it's the color it is-because there's already too many red and black dogs, that color is a one off.
Without a doubt AZ. Owned several DT466's throughout the years and they are dependable but a powerhouse is never in their description.
First thing to go will be the rear springs.
But, but, but, I always have red.
I drove 9 hour round trip to look at a backhoe that had been totally misrepresented. I wouldn't have bought it at half the asking price, nothing on it worked! The owner, a man who has about ten aliases, but one address, I've learned buys & sells tractors, he isn't above fraudulent misrepresentation. He is heavily into modified class tractor pulling. He exclusively uses DT466, claims he can get 1600 horsepower from them before the crank breaks, & the next engine is under $1000. Everything else he told me was a lie, so I wouldn't be surprized if this too was a lie.
I would be willing to bet that a 466 would stand up to making double the power but then it wouldn't be the reliable 466 every one has they last for ever at double the power they wouldn't make it 30 years in a 2 ton because of the typical driver
What power any engine can make depends on how long you expect/or need it to last! The higher you go on the horse power the faster the failures start coming. Also how you use that horse power. A Porsche 911 can be had with a 473H.P. engine but I would not expect that engine to hold up very long pulling a trailer at the legal limits for an 18 wheeler on the interstate! Might make one trip up one of those grades in the Pacific Northwest.
I wouldnt trust what he said the crank braking is just a small part of what happens the block will some times brake into 3 parts.I am about 4 miles from a guy that builds 466s he has 2 dynos. I dont know if 1600 is possible but i think a little over 1000 is. I think i heard a engine can run $40.000. Very scary stuff.
What's the point, get a bigger truck. IMO.
^This! I went back and read that the OP was really talking about hiring to haul customer equipment. Above the 15k excavator he has, I think that's a bad idea.
If he's hauling for someone else, that's a whole different can of worms, I bet he hasn't got DOT #'s and all the insurance and paperwork that goes with that. He's just trying to bill a little more time hauling some stuff for other people. Which is all fine until something happens, then who pays for a $50,000 backhoe that the dump truck excavation company isn't licensed or insured for, or the rental company that hired him to haul it. Sounds like more hassle than I would want. He's in New Hampshire, so I'm going to assume some hills involved. I don't think I'd want more than 15-20,000 lbs piece of equipment behind a single axle dump and tandem trailer, on a regular basis. In flat country with a experienced driver, well that's a different story. I guess I'd want to know more of the original poster's experience, before I would recommend a load. I'm going to guess not a lot of experience, or he wouldn't be asking what's a safe load. SO, I'm going to stick with being under a 20,000 piece of equipment.
I think the only thing you'll kill is yourself, from old age waiting for the top of the hill, the DT466 will make the grade but if you're not in a hurry, you'll get there. I've seen 15t excavators on a tag and they were going down the road at a leisurely pace. I've plowed a lot of snow with one, and well a good push gets it down into 2nd direct, sometimes 3rd low, it does run out of steam in a hurry.
Had a tandem back in the 80's with a 466. Geared to run 62 tops it was really slow at 52,000 getting up to speed and pulled down really bad on hills. How close to the rear axle the hitch is makes a lot of difference how the load balances as well as the well base of the truck. A 5 or 6 speed doesn't have the real low gear to take off with a big load.
One thing to remember using under powered equipment-mainly trucks. Under powered causes traffic issues, doesn't have the ability to get up speed to blend with traffic from a on ramp. Causes traffic to constantly divert into left lane, also has no engine retarder for extra braking. On a hilly two lane causes traffic backup which causes following traffic to get antsy and take chances passing.
I plan my entrances onto the freeway because of that. If I am empty or just a solo load of rock I'll dive on down this short onramp, but with the trailer I go a couple of miles on county roads to get my own lane for getting up to speed. Not having a jake would really suck.
He is hauling the load the truck was built for with only a light load on an unusually heavy trailer. I expect New Hampshire to be much like VT, everywhere you go is mountains, It's uphill or down. His truck is more powerful than mine, but heavier. His trailer is probably twice the weight of mine. Give a little here, take a little there, I think a backhoe is the biggest load he wants to haul. I certainly concede the slow nature of travel is a concern. Mine is NOT slowing traffic below speed limit except trailering. Most of the hills here have climbing lanes. The traffic behind me I feel bad about is downhill. They tend to pass without an issue. Never been on an interstate with it.
I live in a rural area the truck i use alot will mantain 50 with a load on most of the hills around me i dont like pushing it past 55 but every one drives 70. If i am loaded i can take back roads and gravel roads. Thw main highway is very strait with alot of places to pass but you get alot that are afraid to pass.
yeah I don't worry about that Doug if I'm doing 50 they can just leave home earlier if they need to get there faster I just prefer not having a dog that can't make it up over 29 miles an hour on a hill. That's the way I am going over the mountain passes but at least there's other lanes and I can put my four ways on and just hang out over there with the tanker trucks.
My Single axle DT466 had 195hp. Jumping to a 300hp tandem with a 13 speed seemed like a huge jump, and certainly didn't cause as many traffic issues. Still have to plan shifts on the uphill, but has no problem maintaining 50-60mph on hills. Our newest truck is 450hp, with an 8speed, and tows a 15 ton tag like it's not even there. I can point it straight up the hill and keep shifting till I hit the limiter. My dad had a saying about race cars...'how fast can you afford to go?'. I'd say it applies pretty equally to trucks.
I can't even remember the last time I used mine, only used it a few times since i've owned the truck, because 99% of my driving is city. The exhaust brake on the truck I used before was way better because I could use it in the city. Unless you're pulling in the mountains a jake doesn't really matter, if whatever you're pulling has properly working brakes you got nothing to worry about.
Mine tops out at about 55 because I don't want to run it at redline, good enough for me. It has to be a pretty good grade it won't hold above 50 on. I can't complain, at a light it will take off nearly as fast as a new truck pulling a super b weighting 140,000lbs and depending what I got on i'm at 90,000lbs, i'm satisfied with that considering it's 30 years old and I don't push it too hard. I don't think OP has anything to worry about if he put 20,000lbs on that trailer, or even a bit more.
My truck got a workout late yesterday. Truck weighs about 13600, I had 3000 LBS of rock in the body. Backhoe with trailer weigh about 23500. Total over 43000LBS. The Cat 3208 10.4 liter turbo V8 is NOT a powerhouse! The Allison transmission is disappointing in many ways, but in low two gears the torque converter alters ratio to where it climbs anything if traction doesn't fail. Parris hill, named for the notorious family of the Salem Mass witch hunts, is about a mile, rises 550'. It is steep & claims a lot of vehicles in winter. I started up in second, it immediately dropped to first. I chugged up at 15 MPH. Mercifully, not a single vehicle came up behind me. The entire 18 mile trip took 45 minutes. Slow, but a success.
That's a chug. I have a couple of 100 meter climbs at either end of the valley, Ehli hill and South hill. they knock me down to 8th and about 30 MPH @67,000 pounds gross. It gets warm on those pulls.
I use to pull Vantage to the top of Rye Grass I-90 in 8th direct at 80,000 if I wanted to. Normally 7th over-11 miles of 5 to 6%. It was only a slightly warmed up BCIII 400, remember only slightly warmed up.
Yeah. Right. I did a shootout on Vantage with a tarped flatbed with the little duramax 3500 @25,000 pounds. Temp gauge was the governor.
Mine=when pyro would climb to high-I mashed it to the wood to douse the flame.
Empty truck a few days ago went up that grade at 50 MPH, not the case with trailer & big load. It averages over 10%, there are spots nearer 20%.
My father did two terms of two years WWII, then a two year term in the Korean conflict. On the ground, he was an aircraft mechanic, sometimes he flew "engineer". These were radial air cooled engines. They controlled heat with more fuel, and when it became a problem, they injected water. Likely not an option with liquid cooled trucks.
I have almost the exact truck, it's the same year and spec but with the 4 speed Allison Automatic. My trailer is an old Eager Beaver 10 ton, and likely has a weight of around 9000 lbs. My big excavator is a tb153FR and about 13,000 lbs with an extra bucket. I would say it pulls fine on the flats ok but not over 55mph. Any rise on the highway you're down to 45mph. Forget big hills. You can get up slowly, for me it's often 1800-2000 rpms in first or second speed and the truck is climbing at 20mph or so. Around here in Seattle we have 500 ft climbs, and I always go the route with the least climbs. I would say overall, it's too much weight. I will keep the truck and use it with mostly the small trailer for the 4.5 ton machines. I now have a Kenworth T800 and I'm trying to decide if I want to go to a bigger better trailer (with air brakes) etc. On another note, even towing the Eager Beaver Empty, and the dump box empty, the truck is still real slow on the climbs. Heck the truck is just slow period! But it's a great truck. Love the tight turning, automatic, and now my highlift gate. with the 2-speed rear end, it will climb up steep roads, and back up steep inclines. Gets into tight spaces.
Mine is Allison four speed. If I understand, 3rd & 4th torque converter only slips seconds. V configured engines seem to lose torque above 2000 RPM. It'll chug confidently up 20% grades 43000 GCW 1st & second, at 15 MPH, but falters at higher engine speed.
Depends how your allison is calibrated also. I assume its an old MT643. For your application, it should be calibrated for torque convertor high gear( 4th) lock-up only - not in any of the lower gears. When it goes into lock-up, it will feel like it goes into another gear. It can be hard to tell the difference between a shift and lock-up. Being an old fire truck, it may have been calibrated for whatever an individual fire dept wanted.
May I presume checking or changing is only for Allison service personnel?
Yes indeed 500 ft climbs! They're bad long but they're sure steep around here. That would be miserable below 20 miles an hour. I can hold 30 with my setup and the 120 excavator. It's bearable.
This is going way back but I believe the sales and operator literature for all normal configurations of the MT643 were converter only in 1st and 2nd, and would run in 3C then shift to 3L and then 4L. When the World series, 3000 series came out we thought it was interesting because they moved the converter lockup into 2nd gear instead.
short answer, yes. However, the trimmer valves for shift points can be adjusted by trial and error but require removing the oil pan each time you do it so it can be a time-consuming and frustrating job. The best way is to remove the valve body and take it with the little oil-supply tubes to an allison repair shop that has the calibration test bench which they then attach it to and then do all the calibration adjustments. If the engine feels doggy, maybe the shift points are slightly on the low side maybe caused by the valves springs becoming a bit lazy over 40 years. I'm not sure what a shop would charge for a recalibration. Its been 30 years since i had the last one done
"...converter only in 1st and 2nd, and would run in 3C then shift to 3L and then 4L." short answer, yes. However, the trimmer valves for shift points can be adjusted by trial and error but require removing the oil pan each time you do it so it can be a time-consuming and frustrating job. The best way is to remove the valve body and take it with the little oil-supply tubes to an allison repair shop that has the calibration test bench which they then attach it to and then do all the calibration adjustments. If the engine feels doggy, maybe the shift points are slightly on the low side maybe caused by the valves springs becoming a bit lazy over 40 years. I'm not sure what a shop would charge for a recalibration. Its been 30 years since i had the last one done There is a limited amount of information still available for this transmission. What I have found suggests torque converter is variable in 1 & 2, 3 & 4 clunk in. I sense no torque converter action in 3&4.
ok, i was wrong. according to my allison manual, originally configured, the MT640/643 as stated previously should have 1-2-3c then 3L and 4L. also depends how the fire dept had it set up. sometimes fire depts do some unorthodox stuff but not likely. on those engines, if i recall the modulator is a mechanical linkage/cable that needs to be set correctly or the shift points could be affected. i have some information on the old 1980 style brigadier modulator adjustment but not any others. also, the trans governor has to be the correct one as that also affects shift points. if your 3208 is at 250hp, it should be reasonably powered. one place i worked at we had 2 GM tandems with slide-in box sanders and plows on the front and the 3208 power at 250 was adequate for our application. we had some additional shift calibration done but it may have only been 3rd gear hold but i can't remember
It is 250 HP. Turbo, but not a lot of boost. It has adequate power 1st & second. No powerhouse, but it'll climb any hill as long as I'm not in a hurry. I feel that 3rd & 4th are not participating with torque converter. Maybe I don't want them to, I don't want to overheat the transmission. If I weren't concerned with transmission heat, it'd be nice to have torque converter. I sure do miss my old 5 speed Eaton with two speed differential. I'd do a swap if it weren't too complicated.
Sounds like you may be low on power. Have you checked for a restricted muffler? You could remove the muffler and try it without. I don't recall how much boost it should have at full load. Maybe somebody else here does
I was in a somewhat similar situation when I started my business last winter. I had a 2001 GMC C6500 dump truck with air brakes 26K GVW. Cat 3126 motor 230HP 6 speed manual. Pulled a 12 ton trailer with electric brakes. I was running a 310J backhoe on it and it did quite well, but I could really feel it wanting to jack knife when I was taking a really sharp turn that was downhill facing out of my driveway at a very slow speed. The truck was equipped with an exhaust brake that was actually very effective. Coming down a 7% grade was a little uncomfortable without a jake, but it was ok just stabbing the brakes. Heaviest thing I put on there was a Takeuchi TB290, so about 24,000lbs with the trailer. That was the absolute heaviest thing I wanted to put on that rig. When I would go up copper canyon by Camp Verde 7% grade, I just crawled at 30mph with 4 ways. I think the biggest thing is to do a proper pre trip, keep speeds lower, have good tires, keep a very long following distance, remain patient, and expect the 4 wheelers to cut you off and jump out in front of you, and you will get there safely. Also get a dash cam. I just upgraded to a 1986 FLC120 tandem with a 3406B and 13spd and I'm really looking forward to it. Just bought an air brake tag trailer today for it. Can't wait to give it a try!
That setup looked fine, just needed an adjustment on pintle height. You'll like the 3406B with 13 speed, that's what I run pulling 30 ton on my tag and it pulls great.
Yeah, that was when I first bought the trailer. I had to lower the hitch on that truck. I've since sold it. It never broke down on me. What are you running a 3406b in?
With a 3406 b series you will easily almost double your speed up copper canyon I would not have had the guts to do cooper canyon or 13 mile rock with out air brakes on the trailer unless you went down those hills under 40 miles an hour witch would be terrifying with people doing 90 around you
I used to have a 2 axle Chevy Top Kick (yes Chevy, not GMC) with a 16' flat bed dump. Power was a normally aspirated 3208 with a 10 speed behind it. I used to haul my 18k# CAT 416C (including all 5 buckets and the compaction wheel) on a Zieman 2660 trailer (air brakes, aluminum ramps, 10 tn capacity). That thing always let you know where the slightest inclines were! One of the best days ever was when I bought a 3 axle Peterbilt 359 ramp truck. It carried that backhoe like a dream. The OP hasn't said if his truck is turbo or normally aspirated. I know that most DT466 come with turbo but I'm fairly certain that some did not (same with CAT 3208). Regardless I think that around 10 tons of payload will be best with that pulling rig. Obviously you have plenty of brakes. In my opinion your transmission is less than ideal (always hated the 5spd with 2 spd rears). The 10 speed is similar but you don't have to deal with the annoying 2 spd rears. I have a couple of suggestions. Unless you are considering upgrading the tow vehicle (the OP's dump truck in this case), you may consider selling the 20 ton trailer and getting a 10 ton. The only reason is that you are paying a bit of a weight penalty for having a trailer stout enough to handle 20 tons vs. a 10 ton trailer. The other thing I would suggest is that you keep that 466 rung out instead of bogging it to much. In other words be sure to down shift it in heavy engine load situations (like grades) to keep the RPMs up. If your bogging it around that generates a lot of heat. This is what can kill a diesel, especially small ones like the 466. I'm not saying the engine can't handle any stress (they are actually pretty tough and resilient). I'm just offering a suggestion to help you get the most life from your application.
Yeah, I was going down it in 5th at about 50-60mph, I had to come to an abrupt stop once, and it worked fine because I never let the brakes get too hot. That always made me nervous seeing the dummies running dry vans down there at 85mph whizzing by though...
92 Western Star. It's not a combo i've ever wanted more power with it takes a very steep grade to have to downshift grossing 90,000lbs. I just wish it had another gear because it tops out at 55 mph.