Upgrading a M923A2 for Fire Department Usage

[74M35A2]

Not to hijack but are all the alts an issue on a1 and a2. I ask since my a1 has the original

yep

 

[GUNNUT in Iowa]

You are going to want a fancy paint job. http://www.ariseatlantic.org/wp-content/uploads/2016/05/DSCN3448.jpg

http://www.ariseatlantic.org/2016/05/ba-da-ba-da-bing-bang-rally/

 

[check58]

You are going to want a fancy paint job. http://www.ariseatlantic.org/wp-content/uploads/2016/05/DSCN3448.jpg

http://www.ariseatlantic.org/2016/05/ba-da-ba-da-bing-bang-rally/

When I see that photo, I think America!

 

[Swamp Donkey]

I've fought many brush fires in our area and in mutual aid situations over the years. I've seen many of the things that work and and many things that didn't. Here's a couple of pointers to go along with some of the other things already mentioned.

Air lines don't like heat, flames, pointy objects, sticks, trees or anything else that a brush truck would see while preforming it's duties. Protect them well, and there are a lot of them, from heat and snags. The air dryer will also need protection. No air means your spring brakes apply and you now have a vehicle down at the "mercy line".

If you are going to do limb risers or a full outer cage, do yourself a favor and design it for rollover protection. It's far easier to design it in now then to add or modify later. At the very least, build a suitable roll bar behind the cab and mounted to the frame. As was mentioned, rollovers of modified surplus equipment is the leading cause of fatalities with these vehicles. Even with a hardtop, the cab is just a tin can and will do little of nothing in a rollover.

Include a front spray bar under or in front of the bumper. You'd be suprised how many departments don't do this. It's just one extra line and a pipe with holes. If you get boxed in and have to jump the line, this one spray bar will save your butt.

Big Truck = Big Stuck. You need a suitable sized winch.

Keep the young fire chasers out of the driver seat. They think anything military is invincible but the department budget will quickly prove them wrong.

Drive it regularly. Get it up to full operating temperature at least once a week. Brush trucks don't make every call like the other trucks. You'll have less maintenance and repairs if you keep it moving.

Disable the front axle engagement when the T-case is placed in low range system. The department budget will thank you here too.

The best brush trucks I've been around follow the KISS principle. You won't be the first to the scene in one of these, not safely anyway. Drive accordingly.

 

[check58]

I've fought many brush fires in our area and in mutual aid situations over the years. I've seen many of the things that work and and many things that didn't. Here's a couple of pointers to go along with some of the other things already mentioned.

Air lines don't like heat, flames, pointy objects, sticks, trees or anything else that a brush truck would see while preforming it's duties. Protect them well, and there are a lot of them, from heat and snags. The air dryer will also need protection. No air means your spring brakes apply and you now have a vehicle down at the "mercy line".

If you are going to do limb risers or a full outer cage, do yourself a favor and design it for rollover protection. It's far easier to design it in now then to add or modify later. At the very least, build a suitable roll bar behind the cab and mounted to the frame. As was mentioned, rollovers of modified surplus equipment is the leading cause of fatalities with these vehicles. Even with a hardtop, the cab is just a tin can and will do little of nothing in a rollover.

Include a front spray bar under or in front of the bumper. You'd be suprised how many departments don't do this. It's just one extra line and a pipe with holes. If you get boxed in and have to jump the line, this one spray bar will save your butt.

Big Truck = Big Stuck. You need a suitable sized winch.

Keep the young fire chasers out of the driver seat. They think anything military is invincible but the department budget will quickly prove them wrong.

Drive it regularly. Get it up to full operating temperature at least once a week. Brush trucks don't make every call like the other trucks. You'll have less maintenance and repairs if you keep it moving.

Disable the front axle engagement when the T-case is placed in low range system. The department budget will thank you here too.

The best brush trucks I've been around follow the KISS principle. You won't be the first to the scene in one of these, not safely anyway. Drive accordingly.

Good points. I'm not too worried about catching branches and such, we mostly deal with pastures etc... Once it gets into the tree line, we usually drop a dozer with a plow. Cut a line around the fire, and let it burn itself out.

I should point out that this isn't our first go round on building brush trucks, this case just happens to be a bit different. In the past Roscommon (www.roscommonequipmentcenter.com) had designs and detailed instructions on converting military vehicles to wildland units, however since the M939 series didn't come with dual weight ratings, Roscommon considers them a maximum 5 ton vehicle, and has declined to update the schematics.

Since there was a lack on information on the M939 series, I turned to this forum, to get any input on these particular chassis.

 

[74M35A2]

I've fought many brush fires in our area and in mutual aid situations over the years. I've seen many of the things that work and and many things that didn't. Here's a couple of pointers to go along with some of the other things already mentioned.

Air lines don't like heat, flames, pointy objects, sticks, trees or anything else that a brush truck would see while preforming it's duties. Protect them well, and there are a lot of them, from heat and snags. The air dryer will also need protection. No air means your spring brakes apply and you now have a vehicle down at the "mercy line".

If you are going to do limb risers or a full outer cage, do yourself a favor and design it for rollover protection. It's far easier to design it in now then to add or modify later. At the very least, build a suitable roll bar behind the cab and mounted to the frame. As was mentioned, rollovers of modified surplus equipment is the leading cause of fatalities with these vehicles. Even with a hardtop, the cab is just a tin can and will do little of nothing in a rollover.

Include a front spray bar under or in front of the bumper. You'd be suprised how many departments don't do this. It's just one extra line and a pipe with holes. If you get boxed in and have to jump the line, this one spray bar will save your butt.

Big Truck = Big Stuck. You need a suitable sized winch.

Keep the young fire chasers out of the driver seat. They think anything military is invincible but the department budget will quickly prove them wrong.

Drive it regularly. Get it up to full operating temperature at least once a week. Brush trucks don't make every call like the other trucks. You'll have less maintenance and repairs if you keep it moving.

Disable the front axle engagement when the T-case is placed in low range system. The department budget will thank you here too.

The best brush trucks I've been around follow the KISS principle. You won't be the first to the scene in one of these, not safely anyway. Drive accordingly.

Ha! The reason I bought a 925(A2): "Big Truck = Big Stuck. You need a suitable sized winch."

 

[Swamp Donkey]

Good points. I'm not too worried about catching branches and such, we mostly deal with pastures etc... Once it gets into the tree line, we usually drop a dozer with a plow. Cut a line around the fire, and let it burn itself out.

I should point out that this isn't our first go round on building brush trucks, this case just happens to be a bit different. In the past Roscommon (www.roscommonequipmentcenter.com) had designs and detailed instructions on converting military vehicles to wildland units, however since the M939 series didn't come with dual weight ratings, Roscommon considers them a maximum 5 ton vehicle, and has declined to update the schematics.

Since there was a lack on information on the M939 series, I turned to this forum, to get any input on these particular chassis.

I gotcha. Protecting the air lines and getting rid of the auto 6x6 engagement would be M939 specific. Really comes down to how each department uses the truck on the rest, like you said.

You going to do a build thread when ya'll get started? I'm officially requesting one.

 

[Swamp Donkey]

Ha! The reason I bought a 925(A2): "Big Truck = Big Stuck. You need a suitable sized winch."

When did you need a winch? The "Pavement Queen" get a little close to the edge of the driveway?

 

[check58]

I gotcha. Protecting the air lines and getting rid of the auto 6x6 engagement would be M939 specific. Really comes down to how each department uses the truck on the rest, like you said.

You going to do a build thread when ya'll get started? I'm officially requesting one.

I'll do a thread, Its going to be slow going. We just started construction on a new bay yesterday,so that we'll have space to get this thing inside. I'm trying to get several of out newer younger members involved in the work; I figure it will be better treated, if several hands help build!

 

[74M35A2]

When did you need a winch? The "Pavement Queen" get a little close to the edge of the driveway?

You're lucky they stopped the mom jokes.

 

[Nomadic]

Looking at the roscommonequipmentcenter link that check58 posted, I stumbled upon a document that shows the payload for the 939 series trucks. The first part of the doc talks about how there is a limitation with these later model trucks in that the 1400 gallon water tank is too heavy for the weight rating (top of page 6).

The military dropped the weight rating for highway and kept the off-road rating which is "only" 10k lbs. In that pdf is a chart that shows all the weight ratings for each 939 series truck flavor in table 3 at the end of the .pdf file. The m934A2 Van has a 5k lbs payload. Here is the kicker, the Van part weighs almost 10k lbs. So if the Van was removed, the 934 would have the same payload rating as the tractor. Is there a beefed up suspension on the 934A2 trucks?

 

[check58]

Looking at the roscommonequipmentcenter link that check58 posted, I stumbled upon a document that shows the payload for the 939 series trucks. The first part of the doc talks about how there is a limitation with these later model trucks in that the 1400 gallon water tank is too heavy for the weight rating (top of page 6).

The military dropped the weight rating for highway and kept the off-road rating which is "only" 10k lbs. In that pdf is a chart that shows all the weight ratings for each 939 series truck flavor in table 3 at the end of the .pdf file. The m934A2 Van has a 5k lbs payload. Here is the kicker, the Van part weighs almost 10k lbs. So if the Van was removed, the 934 would have the same payload rating as the tractor. Is there a beefed up suspension on the 934A2 trucks?

I would take the REC ratings at face value. Since the military listed the GVWR at 10k, that is what REC used for their calculations. If they were to speculate, then they would open themselves to liability, however they do note that the military based the 10k restriction on the most "severe condition". I know of several of these trucks running 2000 gallons plus equipment, without any problems. In fact, you can barely tell the difference when the tanks are full or empty.

 

[Nomadic]

I would take the REC ratings at face value. Since the military listed the GVWR at 10k, that is what REC used for their calculations. If they were to speculate, then they would open themselves to liability, however they do note that the military based the 10k restriction on the most "severe condition". I know of several of these trucks running 2000 gallons plus equipment, without any problems. In fact, you can barely tell the difference when the tanks are full or empty.

That makes sense from a legal standpoint they need to play by the book. I'm looking at buying a 934 this year and was just curious about the suspension.

 

[Csm Davis]

So my fire department picked up a 923-A2 to build as our next brush truck. While we were at the yard, we also picked up a 900 Gallon SIXCON tank to use for the water storage. I've read several posts on the immediate maintenance, (Working on it, THX for the filter numbers!), and we're also deciding if we're keep the CTIS, (Flashing 5 lights, still can't find any leaks). Overall the truck looks like it went through rebuild at Camp Shelby, then very quickly went to surplus. If I'm not mistaken, the truck came to us from Shelby. I know we have to do something about the alternator, as it won't put out enough juice for what we need to add to it; so I'm working on that issue. I do wonder, has anyone made mistakes on converting one of these trucks to firefighting that they wouldn't mind sharing?

Okay check58 so if you need it I can come up and help out on some of your problems where exactly are you? Starkville? Thought y'all had lot's of cow bell engineers up there? But hey if you don't mind a USM alumni working on the truck I would be glad to lend a hand.

Sent from my SM-G900V using Tapatalk

 

[check58]

Okay check58 so if you need it I can come up and help out on some of your problems where exactly are you? Starkville? Thought y'all had lot's of cow bell engineers up there? But hey if you don't mind a USM alumni working on the truck I would be glad to lend a hand.

Sent from my SM-G900V using Tapatalk

HAHA, I might take you up on that. Yes I'm in Starkville, I actually work for MSU. My office is 100 feet from the stadium. Southern Miss grads usually don't bother us, it's that Ole Miss crowd that causes problems!

 

[NEIOWA]

.could you measure your sixcon? What I'm looking for is the height from the bottom of the cage to the top of the tank (not the top of the cage). IE: if needed to reduce the overall height by removing the top portion of the frame/cage would one "gain" a few inches

 

[Csm Davis]

Check58 did y'all get the truck up and going?

Sent from my SM-G930V using Tapatalk

 

[check58]

I'll be happy to get you measurements tomorrow night. Honestly if it reduces the overall height by more than 2 inches, I'll be surprised.

 

[check58]

We're slowly getting there, We've got a "parts truck" to pull a hardtop and toolbox from. As with any budget build, sometimes you kinda have to wait to get a good deal on parts. I will say we do have all of the major components, and its parked in a bay. I'm planning to order an alternator from 74M35A2 here in the next couple of weeks.

 

[NEIOWA]

DRMS has had MRAP alternators listed in new condition in RCP. 400+ amp. No cost to FD and if in RCP status they pay the shipping to a UIC you designate (such as a local NG armory).