New First Out Truck Questions

[hilltopvfd]

Our department is in the initial stages of determining our new large brush truck, which will also be first out for vehicle fires and act as the second engine in our 2 engine dept.

We don't get many structure fires, and our predominant fight is brush/grass. We are rural with our supporting rural departments at least 15 minute away with small 200-300 gallon skid mounts. Our terrain is predominantly sand, and there is considerable wooded area with dense undergrowth surrounding us, interspersed with hay pastures.

We have successfully used an older Chevy C-60 with a 900 gallon homemade tank and small Gordon-Rupp pump. Now is time to upgrade due to a grant we received.

This is what we have got in our sights at the moment, and I would appreciate any input pro or con. Of course we are dealing with a handful of vendors now, and they all tell us differing accounts, so some non-biased input would be great.

We are looking at most likely Freightliner 4x4, with a 330 Mercedes, and Allison auto. The targeted GVW would be 33,000#. Not real sure if it would not be better to go with a twin screw rear end, and lose the front drive, substituting wider floatation tires. We are going to mount a 16,500# winch in the front bumper so that might offset the lack of front pulling power. Another reason to think of the twin screw rear end would be the possibility of converting this chassis to a tanker in the 3000 to 3500 gallon range when the grant period expires.

The main reason for going with the Freightliner is the president of our VFD board wants a re-hab area, since the bulk of our volunteers are well into their retirement years. The Freightliner is the only one that offers the extended cab with the suicide doors. We do not want to go with a 5-man cab, since that would mean more airpacks when we outfit it for our PPC.

The closest Ford and GMC dealers are over 2 hours away and FL and International are 45 minutes off.

We are going to outfit it with at least a 1000 gallon poly tank, CAFS and remote monitor on the front bumper.

We have settled pretty much on 500 GPM for the fire pump capacity, as our primary engine has 1250. We won't get full credit for an engine, but around 92% if all other equipment meets the standards.

Anyway, now the debate rages over a cross mount or PTO. I read another thread on this concerining the pump and roll capacity, but I didn't see that the truck mentioned was outfitted with CAFS. The pump and roll is important for us to have, as currently we use our smaller skid mounts in the same way, laying a line of wet water/foam as containment or intercept. With CAFS, this should even be more effective. But with the compressor being mounted on the engine and the pump PTO, I am not sure we wouldn't wear the equilibriating valve out the first time with the engine speed fluctuations.

I pretty much understand that the cross mount would negate all these problems, but not real sure what the difference in costs would be, although I have an idea we aren't talking a huge difference. Once you figure in the installation from both a plumbing and PTO standpoint, I doubt it would cost much more to go with the crossmount complete package. The system we are looking at now is the Waterous/Pneumax, so any pros and cons with those would be appreciated as well.

Even with the crossmount, we would still have the compressor on the engine, but I don't think for the demand our pump and roll exercises would put on it, it would be a problem.

One last thought would be since we are going heavier with the chassis, if steel might be the better option than aluminum, since off road usage has a tendency to stress and crack welds. Steel would be much more repair friendly than aluminum. Of course we would have the problem of rust, but we can take care of that with proper maintenance.

I know its a lot of money for a brush truck, and a lot of equipment, but it will work, and will be worth the money. We aren't planning on jumping a lot of stumps with it, the C-60 won't be scrapped, just upgraded with a new tank and pump unit.

So any advice you have on chasses, or pumps, CAFS, or anything else would be appreciated.

[donethat]

Sounds like you have most of the bases covered.
Have you considered a 6 x 6 allwheel drive chassis. Good for open prairie but not for hills, gullies, and ravines. As for pump and roll, if you have a manual spicer 5 speed transmission and a two speed 2 to 1 reduction transfer case, the pto driven pump will pump and roll just fine. If you go with an automatic transmission, then a cross mount engine driven pump is a much better choice for pump and roll.

[blmoore20]

We are in the early stages of specing a similar truck.

We are looking at a 4x4 International, 500gpm PTO pump and a 1700 - 2000 gallon tank. This is primarily for water supply but will also be used for brush.

Here are some initial thoughts:

From what I understand (I'm sure someone will correct me if I'm wrong ) A 4x4 chassis has to use a PTO pump as a midship pump requires a "transfer case".

Again from what I've read (on their website) International offers a factory 4x4 system where Freightliner does not although I haven't talked to a dealer yet.

If you are concerned about rust, welds etc. you might consider a poly body, we are. They are lighter than steel, they flex with the chassis. They can be repaired easily and they look good. There is a company in NH that builds them and they are very nice.

I hope this is helpful. Congrats on your grant and good luck with the truck.

[hilltopvfd]

Freightliner has just added 4x4 to their line, its new. From what the dealer says, what we are looking for is around 60K with a 90 day lead time.

My terminology is probably not correct, but when I use crossmount, I mean a drop-in unit with its own power supply, not a midship.

I have heard the poly bodies look nice, but are susceptible to cracking, as the technology is still new. Again, have no experience with that, but going off road would stress it even more, so if there is a grain of truth to that then we could be in for a long ten years. Any advice here would be appreciated.

Thanks for the advice on the tranny too, but with our department, the automatic is the only way to go. Hard of hearing guys have hard time determining where the sweet shift points are, but I guess it evens out for them, cuz they can't hear the gears grinding either, lol. Maybe that is it, or not. We have a Ford 9000 with a 5 speed with split rear end.....it gets abused mightily, and even the little Chevy brush truck gets it share of
redlining.

Congrats on your new truck as well.

Thanks for the input, keep it coming.

[stickhead6]

hilltopvfd, You may want to consider contacting Smeal Fire Apparatus, they have done many crossmount type units. Check out there new delivery area and locate the crossmount section. Good luck in your purchase.

[buckdog]

Check out Boise Moble Equipment, they specialize in this type of unit.
www.bmefire.com

[Ledebuhr1]

Anyone know how pump and roll works? How does the pump pump water consistantly when the engine speed varies?

[backsteprescue123]

Anyone know how pump and roll works? How does the pump pump water consistantly when the engine speed varies?

That's a good question. I've always wondered the same thing. Is there a small engine just for the pump or what?

[TenderR6]

Anyone know how pump and roll works? How does the pump pump water consistantly when the engine speed varies?

My Tender/Tanker has a Gasoline Pump but if you have a PTO Driven Pump the clutch has to be out so the transmission/pto gears are turning. The PTO speed will vary with the engine RPMs. Some pumps are mech conected others hydraulicly. So you can vary that way also. Smaller pumps can be belt driven off the engine thru hydraulic pumps. They make constant flow hydraulic pumps that bleed off excess pressure and keep the flow at a set GPM and pressure as long as the engine is turning fast enought to make it. You don't pump and roll at high speeds so depending on what gear your in it could be just a straite PTO driven and you match the engine RPMs to the pump. Mark H.

[HFRH28]

Our tankers with Pump and Roll can only do such in first gear (granny gear). GPM varies with engine RPMs, so low idle= slow moving truck = low flow but higher idle = faster moving truck = more GPM so you have to find a happy medium should you do such. (Note these trucks have true PTO, not a wet-line (hydraulic) PTO conversion)

[hilltopvfd]

thanks for the links, i have also been looking at weis fire and safety...

the thing i haven't seen yet is CAFS on pump and roll, which might be even trickier, when you add the compressed air component.

[Res343cue]

thanks for the links, i have also been looking at weis fire and safety...

the thing i haven't seen yet is CAFS on pump and roll, which might be even trickier, when you add the compressed air component.

Check out Annaville Volunteer FD....

[Resq14]

KISS

Get a system like a Snuffer that has its own engine.

Self-contained, powers the compressor and pump... simple. Yes, it is another engine to "maintain."

I wouldn't do a big truck this way, but for something like this, sure.

[npfd801]

I'd look at something like S&S's units, the Rosenbauer Timberwolf or anyone else that has done an urban interface type vehicle. I'd think pushing an urban interface vehicle into a more pure wildland application would be easier than reinventing the wheel.

We have a Rosenbauer NH pump equipped rig which is a PTO unit, we can pump and roll as well as do a "similar" to CAFS foam (I know, it isn't CAFS) with the Rosenbauer foam system tied with the high pressure side of the pump. Again - this isn't a solution for everyone, but it wouldn't hurt to look this route. The Rosenbauer foam/pump combo is a cheaper alternative to CAFS, but again - you don't have some of the flexibility of having a true CAFS unit.

To be fair, when we soliticted competitive bids for the same unit, one builder proposed a Hale pump based on a European market unit that is somewhat comparable to the Rosenbauer pump - so other options may exist. I don't think it had a high pressure side to the pump, but I just want to suggest options I'm familar with. I want you to end up with a rig that meets your needs, regardless of what builder's badge is on the body.

To me - putting 1000 gallons on an extended cab 4x4 Freightliner doesn't seem out of line. Going with a tandem axle rig (and the length it would need to be to at some point to carry 3000 gallons as a tanker) would seem to really kill maneuvability.

Also - I may be ignorant on the issue, but I haven't found anyone offering a prepackaged CAFS foam/pump combo, self powered, at a 500 gpm rating. That might complicate things.

I''d check the above folks' sites though for more info.

[ChiefDog]

We are looking at most likely Freightliner 4x4, with a 330 Mercedes, and Allison auto. The targeted GVW would be 33,000#. Not real sure if it would not be better to go with a twin screw rear end, and lose the front drive, substituting wider floatation tires. We are going to mount a 16,500# winch in the front bumper so that might offset the lack of front pulling power. Another reason to think of the twin screw rear end would be the possibility of converting this chassis to a tanker in the 3000 to 3500 gallon range when the grant period expires.

I don't have experience in the type truck you are talking about. (Interface type truck) But you are not going to get 3000-3500 gallons on a 33,000 gvwr rated truck in your "future" modification. Do the math 8.33 X 3000 is 24,990 lbs, the chassis alone is around 10,000 lbs so you are over the GVWR with No tank, no equipment etc. It isn't going to be safe so don't even think about it. If that is what you need then you need a third truck.

Step one is figure out what you want the truck to do. Interface or Tanker. How much money you got to spend will determine alot of what you can do.

That is why you have different tools in the toolbox. You have finish hammers and post mauls.... both are hammers but do very different jobs.

[hilltopvfd]

Well, we are looking for a true CAFS system for ISO, which in Texas would require a 500 GPM water pump for full credit as far as ISO is concerned.

The debate rages within our department that we wouldn't get full credit for the 500 GPM pump, but we would with a 1000 GPM pump. One side of the argument is that you don't need more than 500 for CAFS since the system would not require much more than 2 GPM per single CFM the compressor would deliver. And since compressors are limited to the 200 CFM range, then around 400 GPM would be optimum pump for CAFS. The other side says that we could use the 1000 GPM as a transfer booster pump in line to move water to our primary engine. But that would take the CAFS out of the fire fight and relegate it to water delivery. The ISO consultant we are working with says that the 500 GPM will give us 92% of a full engine if the rest of the requirements are met on the truck. So do we spend the extra money on a PTO 1000 GPM midship system to get that extra 8%? Or do we save it for putting towards another tanker? To me the marginal return on that money would be on the tanker. Plus take into account that the pump and roll capabilities of the independently powered unit would be seamless, the real question comes down to whether we can get results we can live with from a PTO powered CAFS system behind an automatic tranny.

Waterous has the separately driven units in this range and beyond...From their site: "Waterous has fifteen foam systems currently available to the firefighting industry, ranging in size from 70 GPM (265 l/min) of water and 35 CFM (0.9 m³/min) to 2,000 GPM (7,600 l/min) and 200 CFM (5.6 m³/min). These units are available as PTO-driven, or modular slide-ins and integrated cross-mounts with optional gasoline or diesel engines." I am sure other manufacturers have similar units, just haven't looked deeply into them yet.


As far as the carrying capacity of tandem/twin-screw vs. single axle, I had already determined that adding the extra axle would increase the carrying capacity considerably. I just didn't say it for sake of brevity, guess I thought that would be a given. But as i wrote it, I can see where someone would think 33,000# would be the target GVW with or without the twin-screw. The "future" comment was referring to buying a truck that would serve the purpose now as a brush truck, but have the capacity to switch it over to a large tanker at some point. And the 6x4 or 6x6 would not hurt us except for maneuverability, in fact it would provide more floatation on this sand. But our need to get into tight spots overrides the advantage of the extra rear drive axle. So that whole issue is probably moot anyway, as we are leaning to 4x4 now. It was just forward thinking to consider buying a chassis now that could handle a large tanker later on if we wanted to convert. Just didn't want to get caught 10 years from now thinking "if we would have only..."


Thanks for all your input, it will all serves putting a better truck in the field for us!

[mohican]

Have you considered a front mount pump (driven off the front of the engine) or a rear mount pump driven off the PTO? Either of these methods would keep the tank up against the cab wall, and the water centered more than with a slide in skid. Rear mount pumps/Cafs are available, and at least one pump manufacturers are beginning to package the cafs compressor together with the pump unit on some models. Darley also has under the hood CAFS compressors that would be driven by your serpentine belt.

if you go with a front or rear mount pump, I dont think that the cost will be much more for 750 or 1000 gpm than it would be for a 500 gpm. I would get at least 750 gpm.

Pump and roll works at varying engine speeds because you are not typically requiring a lot of gpms. also, it has been pointed out that you operate in low range, or low gear or both off road so that your rpms are up compared to ground speed. There is also the optionn for having a front or rear mounted pump hydraulically driven, but I don't know how much gpm. I have a some experience with using a front mounted pump in pump and roll situations and the engine speed variation has never been a big dear.

other things you may want to consider is whether you want dual rear wheels or "super singles". I have seen some articles and such on short wheelbase, 6x6 trucks with super singles vs duals. In sand or sometimes mud that may be the way to go.

[neiowa]

Have you looked at a hydraulic driven pump (pto driven hyd pump/hyd motor driven fire pump). Eliminating the purchase/maint expense of a "extra" engine would be a very good thing.

In your size range certainly go to 6x6 (or 6x4/twin screw) is a very good idea. Better option in all important areas. That front drive axle is going to cost you some big bucks and not maint free.

[CFDC10]

It seems like everyone has given you some great feed back to back to your dept. with. I would just add that what ever you do stay away from the wider floatation tires or "Super Singles.I am an officer of a fire Dept. and also drive a concrete mixer full time, and have seen the damage that happens when a blow out occurs,also the tires are great off road when conditions are optimal but when faced with mud,snow or anything less that a hard surface duels are the way to go. We to purchaced a 6x4 International 750/1500 that acts as a tanker and brush truck, with a Hale pump with the ability to pump and roll. Ours has a mid-ship pump with two 1 3/4 mattedales for stuctures and two 1 1/8 reels on the back step for brush and one 1 1/2 forestry line. We also carry a 1500 portable tank, as the truck is out fitted with a dump valve for tanker shuttle opps.