Dump truck motor options

[DKinWA]

I've been looking for a tandem axle dump now for over a year and I'm not finding what I want. Now I'm considering a new Kenworth T300 or Pete 335. I priced a T300 with all the goodies, 16' dump box and gear and it was a little shy of $100,000. Now for the question. The biggest motor you can get with the T300 and 335 is a 330 cat or 315 cummins and I'm wondering if these motors are big enough?

I live on the coast of Washington and I'm typically working on pretty flat ground. There's a few hills around here, but they tend to be outside the area I work in. The truck will be used as much for moving equipment (#10-20K) as it will be used for hauling dirt and rock. A typical load would be under #54,000 unless I buy a tandem axle pup and then it might jump to #80,000.

So..... how do you think the 330 cat or 315 cummins will work in my situation?

[Nac]

For a tandem I think it is a little light on the HP. I am waiting on my rooloff I got it coming with 485 HP Volvo Just bump it up but its is a tridem 80,000 GVW.

[Ford LT-9000]

You are looking at pretty light spec'ed tandems you should be looking for a T-800 Kenworth with minimum 425hp don't kid yourself if you think 300hp is going to-do it. Minimum 13 litre power I don't think there is such a thing as 14 litre power now its 15 litre.

You spec a truck with low power you will be shifting alot which means you will be exhausted after a days driving.

For a dump truck I would be looking for these specs

T-800 Kenworth C-15 Cat or ISX Cummins (450hp) 13 or 18spd 18,000lb front axle with 46,000lb rears. If you can't afford a Kenworth then look at a Sterling LT9500 with the same spec's.

[Orchard Ex]

I just ordered a Pete 335 (but it's a S/A) - very nice trucks. For the work you are describing I'd have to think that it would work OK with the right transmission. Which one were you thinking about?

I'm starting to see more T300/335 tandem dumps in my area so they must be doing OK. - Not too many hills around here though.

IIRC - the ISC gave 315 hp and 950 ft lb torque and the C7 330 hp and 860 ft lb torque on the upper ends of the spec.

One more question - Are you planning to stay at a tandem or add a tag axle later? 'Cause that might change my whole line of reasoning...:)

Let us know if you get one,
Regards,
Korey

[DKinWA]

Good memory orchard on the torgue specs. I actually spec'd the 315 cummins because of the torque values when I met with kenworth. The rest of the specs were 40,000 rears, 14,600 front, 10 speed and a whole lot of little goodies. We didn't discuss adding a drop axle, but I was planning on adding one.

I'd love to have a T800, but I'm not convinced the extra $45,000 is a good business decision right now. If the truck were hauling rock 8+ hours a day, I'd feel differently. Right now if I need to spend all day hauling rock, it's more cost affective to have the pit deliver with their trucks. This way I stay on the dozer and I can have a couple of their trucks rolling and get done in a third the time if I hauled the rock. If I was to guess, I'd say my hauling is 30% machine towing, 25% rock, 25% dirt and the balance hauling stumps/brush. So in reality, 75% of my loads will be well under 54,000 and probably closer to 45,000 in the 16' box.

I'm really not sure what to think since I've got a F800 SA dump with 225 cummins and it does fine under 30,000. I won't be the first at the finish line, but I'll have a smaller fuel bill when I get there:) With fuel costs going up, I'm really looking to find a truck that will do what I need and not break me up in fuel costs.

[Jeff D.]

:thumbsup DKinWA,your last post is very similiar to how I feel.It's real nice to have the best of everything.More power,bigger axles,bigger everything.But it make a huge difference in the price.Maybe 30% or more from cheap specs to top-o-line specs.

It's finding the truck that'll do the job,and leave you with enough left over to buy other equipment.Everyone has a different level they find acceptable in a truck.Mine is apparently lower than others.I just want it to do the job,and be as dependable as possible.

I'll give up some niceties in order to put more ching in the pocket,as long as it's capable of doing the job.

[woberlin]

I have to agree with Jeff D. Big power would be great to have, but at what cost. If most of your driving is on fairly flat areas, and your only grossing 54,000 you should have more than enough power. How fast do you really need to go, the max speed limit here for a truck is only 55 mph. My 68 Mack only has 235 horses, and I regularly gross 54,000. I have no trouble getting up to or maintaining highway speed on flat roads. Hills, now thats another story, but I still get there. Good luck on your purchase, I'm green with envy, I'd love a brand new truck, even if it only had 315 hp!

[Dwan Hall]

1988 Ford L9000 w/315 hp cat, top speed 68mph, empty 23000lb loaded to 54000 lb it will still do 68 mph up hill or flat ground. I pull an equipment trailer w/Takuchi TB070 around 25000 tow weight. even with a load it has enough hp to satisfy me. I think you will be happy with eather the Cummins or Cat.
Wish I could worent a new truck but my used one with 500,000 miles will have to do for a while.

Dwan

[Ford LT-9000]

For us here in B.C. max gross for a tandem axle dump with a 16'6" box is 57,500lbs. Rule of thumb is the truck has to beable to carry 15 ton and up to 17-18 illegally. We don't run lift axles they are a pain in the azz plus they are not legal here.

If I went and bought a 2005-2006 Kenworth T-800 West Coast spec'ed it would cost me 140-145,000 dollars I can get a Mack Granite west coast spec'ed for 138,000 Canadian. Not many people choose price over power if you are driving this truck it has to have power. When your pulling a 10% grade you need some jam when decending the grade you need a strong JAKE.

We have a few trucks around here with L-10 M-11 and 3306 (300hp) power they are SLOOOW up the hills they are climbing them in second gear. Your constantly shifting to maintain any speed if you don't float the transmission your leg would fall off.

If you order a truck with 40 rears then make sure they are open diffs if your doing any kind of offroad work with a loaded truck and you get into some soft ground those 40 axle shafts snap like tooth picks.

[95zIV]

If you're not doing a lot of hauling which is what it sounds like then the small cat power sounds fine. The company where I work has a '88 General that has a 350 in it and it spent most of it's life hauling a pup at close to or more then 80,000. We're in pretty darn hilly country around here and that truck did a beautiful job. In fact the new granite they've got the driver hates it. As for a tranny behind it, the ten speed sounds good, 13's and 18's are just too many gears. If you think you might need some real good creeping around a site then I'd suggest an 8LL, those are very popular and as bullet proof as it gets.

[Ford LT-9000]

I hear the Mack Granites are hit or miss. Mack transmissions have always been miserable to shift. The Mack I drove had a Mack 8spd it definatly lived up to can't find it grind it.

If you buy a new Mack make sure its got a Fuller transmission behind it. As for transmissions a 13spd isn't too many gears its only a 8spd with the option to split the top half. Most of the time you drive the truck as a 8spd empty and loaded you use the splits to keep the rpm jumps down.

When you have a underpowered truck make sure your good at floating the transmission if you have to use the clutch your leg will be laying on the floor. You would probably wear the clutch linkage out so keep lots of grease on it if you have to shift with the clutch.

A trucking company I know has a Freightliner tandem flatdeck with 3126 Cat power with 40 rears and 12,000 front truck has a 9spd in it. The drivers say your constantly shifting when loaded. Going down the hills is another story you really have to gear down and watch your speed.