Has anyone herd about or seen this problem with the ALF rigs.
"LINCOLN - Residents who pay taxes to the Albion Fire District may have a big problem.
The 42-foot, American LaFrance ladder truck they bought in 2002 is off the road and in storage even while the district continues to pay down the 12-year, $340,000 loan at a rate of about $30,000 year. Interest alone is $30 a day.
Ladder 20 has several problems, but the biggest is that once it hits a certain speed on the roadway, it begins to bounce. The rocking from front to back is so severe that the department's insurance company, Volunteer Firemans Insurance, ordered the truck out of service. It's sitting at Station 4 on Mendon Road in Woonsocket with 11,525 miles on the odometer."
Alright I looked it up & it seems to me that the axles are out of balance. The front is too heavy and the rears are too light. Hence the bounce due to the rear throwing weight to the front axle and the front axle throwing the weight to the front.
I would keep that ladder out of service myself with the severe bounce that was in the video. The Woodbridge fire department just put in service a 110' ALF/LTI aerial about 2 months ago without any problems, they are one of nine fire departments in our township. I would take the offer from " Pierce " and buy there aerial for $ 660,000 !
Originally Posted by QFL313
QFL313 are you from the area or did you just happen to find the article?
Hate to take you to task FireBuf but that is not the problem. If anything it is to light on the front axle. This truck does not have a pump or tank, which would lighten up the the front axle. And how does one axle THROW weight to the other? Never heard of that before. It's a ladder truck not a see-saw.
I know some people involved in this mess and the truck has spent more time out of service than in. Most of the mileage has been from going back and forth from the shop to the station.
It will be interesting to hear some of the comments from those on the Happy Birthday ALF thread. Lets see them blame this on a component supplier.
There is a video floating around that was done by the fire department that shows what it looks like from in the cab as well as from the outside. About 5 minutes long. It's worth finding it if you can.
Actually you both are correct in, well..some fashion. What is being seen here is a phenomenon known as 'porpoising' It's very common in motorsports. Basically what is going on is that the front end of the truck is too stiffly sprung to compensate for the weight that is actually being carried. The dampers(shocks) or whatver provides for the bump damping in this case is fighting the action of the springs. As the springs flex(compress) the shocks are pushing back harder than the springs push up..eventually a decent rhythm is found and it just carries on by itself. The only way to solve it is to reduce one of the variables. Either softer springs, or by re-valving the dampers. And the fight I speak of isn't a front end only, it's a fight between the front and rear suspension.
Originally Posted by tomwnh
they should fix it or buy it back no excuse for that on a half million+ truck
Smart idea! Best one I've heard in a month!
Originally Posted by PierceGuru
Tomcat,by chance you know who's suspension is under the rear? And the issue with this rig goes beyond springing/damper valving.Watch the video carefully and see the cab/to rear body movement.That's a lot more than just a suspension issue.Something(like maybe wheelbase)is bad wrong here.Glad it's not mine. T.C.
does anyone know if this just started happening? wonder how long the truck sit's before being moved, with it being a 2002 and only almost 12,000 miles on it, a couple of our trucks get a bounce in them but not near as bad as that, from sitting for a while without being drove, b/c the get a flat spot on the tire where it was sitting, but it you take it out and drive it for a little bit and get the tires warmed up, it goes away. but I wouldn't of wanted to be the one driving that truck anywere with a bounce like that, can only imagine the stress it's putting on the frame.
Originally Posted by QFL313
from what i've been told(now don't quote me b/c im not too familiar with the particulars on the truck since it's not a truck i drive) but what i hear from some of the guys is that the frame is greatly reduced as it goes under the cab of the truck and even more so where ALF cut into it to fit the engine down lower to fit in with the low profile cab which makes the front a hell of alot weaker which causes the shake, rattle and roll
good idea, matter of fact it's what a fair amount of people thought at the beginning however i heard that was checked out and wasnt the case, an engineer who specializes in this sort of the thing when through the truck head to toe, the hydraulics are severely deteriorated and alot of cracks were found in the body of the truck when they went to repaint it b/c of a paint defect
Originally Posted by fire0099881
Frame Rails ?
Any one know what type of frame rails are on the ALF aerial ladder. single,double ?
It can be found here (atleast partially) by scrolling down a little bit. You do not need to register. valleybreeze.com
Also--more info from another forum:
QUOTE/ Post # 1: Albion Rhode Island Fire Departments 2002 ALF Eagle Ladder Truck "Shake, Rattle and Roll" issue has forced its Department to look into taking legal action against American LaFrance as it pertains to Ladder 20. The issues, which according to the Cheif of the Albion RI Fire District, has been looked into by officials and engineers of American LaFrance on at least 2 separate times, without relief. Apparently the rig Shakes and Rattles once the apparatus reaches speeds between 25 and 45 MPH. The Fire District is now looking into purchasing a New Pierce Arrow Ladder Truck and Pierce is willing to take the ALF Rig in as a trade in. Go the following Web Site and then click on where it says "Albion Fire Truck Video" to see for yourselfs what their complaint is all about. http://www.valleybreeze.com/
Albion Fire District
Special Taxpayers Meeting
Monday, January 22, 2007 at 6:00 pm
The meeting will be held in the apparatus bay
Albion Fire Station
38 School Street
Albion Rhode Island
The purpose of the meeting is to discuss and vote to replace Ladder 20 as well as a vote to take legal action against the American LaFrance Corporation. Registered voters in the Town of Lincoln residing in the District of Albion are invited to attend. Christine A. Morrissette
District Financial Officer
Post # 4: Sounds like a drivetrain issue. Probably an unbalanced drive shaft. I should read more into it , and wonder if the unit has a pump , and if it does what make and model the pump is. That to me sounds too simple, but with the speed being a factor they have already rebalanced the tires and checked the rims. (I hope) The driveshafts would be the next to check , but can remain a problem if the correct shafts are not used in conjuction with the correct pump. The next area to look into would be the rear. Other than not driving it that would be my angle of approach, but I also question the axle weights and overall truck length and wheelbase. Too light a rear and trying to compensate with a heavy front will give you "rock and roll" . Like I said , I have not looked into it any further than the original post. Has anyone tried to seperate road speed and RPM of the drivetrain?
Post #5: Just saw the video. The truck is short, high and is fighting itself. I would love to see a spec on the unit , but watching the video( and the clarity is not that great) I have to go back to the part of my post that stated the axles are too light in the rear and they tried to compensate with a heavy front axle. The rears are throwing the weight to the front axle and the front is throwing it back to the rears.
Re: Albion Rhode Island Ladder Truck Issue
« Reply #1 on: January 12, 2007, 07:22:57 AM »
I saw the video and man that is a major problem. It looks like a combination of a chassis and suspension problem. Going down the road, that chassis looks like its bending, I wonder if it could be torque issues with the transmission. Definately need to see all the specs on this one so Albion didn't over look something hopefully and I really think they got hosed. When we went to bid on our truck we looked at ALF since we had a 1981 Century, which. It was a really good and reliable truck for us. We had nothing bu problems with the dealer (who will remain nameless) with them giving us specs totally wrong or not what we want and we had to chase them where they should have been chasing us. Their attitude was we have an ALF so were gonna get another, NOPE!
Hopefully Albion will get this issue resolve, no manufacturer should let a truck acting like that out of their shops!
Re: Albion Rhode Island Ladder Truck Issue
« Reply #2 on: January 12, 2007, 01:56:39 PM »
This truck is sitting in our station 4. I looked it over a couple weeks when I was working OT there. From what I've heard the front frame rails are single channel not tripled up as is the norm in a ladder. This would explain the torsional shake seen in the video. It's too bad, apart from the cheesy plastic interior in the cab, it looks like a pretty well laid out truck. /QUOTE
This is only excerpt--the rest was some brand bickering.
Well, going on video evidence only, it screams suspension problem. I've spent a fair amount of time in suspension setups, albeit, in a smaller and lighter vehicle.
Originally Posted by Rescue101
Basing on my knowledge of HEAVY chassis,this rig acts the same as our medium wheelbase heavy wrecker only exaggerated.With a heavy load on the underlift you'll get a light "hammering"with ours at just about 35mph,goes away either side of that.You can also get this condition with a dump truck when the chassis is too short or the centerpoint of the rears is too far ahead.The underlift shifts a lot of weight to the rear and unloads the front. Not knowing what this ladder has for suspension or centerpoint I can't speculate further.However,ten years of wrenching in heavy truck would lead me to believe this problem is deeper than just springs and shocks.Waaay too much flexing going on.Be interesting to see if anyone ever figures it out.Looks like Valleybreeze is looking for a key change.Fixes all known automotive problems.Either way it's not a vehicle I could put a lot of faith in,given that it's a new EMERGENCY vehicle. T.C.
Do any of you guys think that the pulsations from throttle harmonics could be causing this chassis flexing? From the video the rig doesn't look like it is going all that fast. I've experienced it around 30 MPH. And once the throttle harmonics set in the pulsations do get pretty rough until you let off of the throttle. I know from experience. I wonder if someone could tell us if the engine is pulsing while the rig is flexing?
Originally Posted by IronsMan53
That's a great observation. I have had that happen many times to me in our E One 1000 gal pumper tanker, it's a long wheel base I believe Hurricane chassis. It responds like that.
It looks like a way too flexible frame and a harmonic being set up by a combination of the road surface frequency, the spring rate of the tires, front and rear suspension spring rate and the shock dampening. Maybe some throttle bounce thrown in.
Years ago we had a snorkle aerial that would bounce you out of the drivers seat if you kept the speed constant at about 35 mile an hour. The chassis manufactuer, Hendrickson (now gone) changed the front tires from a Goodyear cement mixer type front tire to a Michelin Pilote type tire and about 90% of it went away. By changing to a different type of tire it changed the spring rate of the front suspension system and changed the frequency of the harmonics.
I'm down with the Throttle bounce theory.
I wonder if the department or dealer has investigated that possibility. If it is throttle bounce, Lifting your foot off the throttle for a split second will make it all go away. The combination of a rough road, an air ride driver's seat, and not having the heel of your boot on the floor can result in the "bounce" - leave your foot on the throttle after sensing the bounce - and go for a bumpy ride.
That's my guess.