Lift-Axle for flatbed

just curious. for the guys using the Hendrickson UBL or the Jost set up or even the guys like Autocar and the others that have made their own setups (nice job by the way) what do you do about the abs. I have the Meritor 4S/3M abs module on my 2004 Fontain step deck. I realize some of you may only be using the Meritor 4S/2M or 2S/2M series module, but i'm sure someone has the same setup as I do. I just hate to be rolling down the highway with a trailer ABS light on and even more so if the DOT sees me or the scalehouse catches it. just wonderd what some have done to avoid the ABS light coming on when the front axle is up and the wheels aren't rolling.

Maybe wire in a secret toggle switch to the ABS light to shut the power off while the axle is up!!! lol.......

 

Snowman,i would contact Meritor and ask them.
A simple setup like Autocar has will not work for you.

 

Look in your ABS manual. It tells you which sensors to switch when using a lift axle. download a pdf from their website if you didn't get a paper copy with your trailer.

IIRC each sensor controls a side, L or R. You need to switch around the cables at the control unit so each module controls an axle, Fwd or Aft.

 

Yeah your right about the sensors semi crazy, a lot of systems just a use one axle and a sensor for each side on that axle going to the ecu/module. the problem i'm having is that I have 4 sensors, one for each wheel.meritor 4s/3m. I just put a new abs module and valve on last year and I hate to switch it to the 2 sensor system,2s/2m.

good thinking on the meritor site. I went on there and it looks like theres a kit you can buy to tell the ecu on the abs module that one axle is up and it corresponds with the abs so theres no fault codes activaited.

Has anyone used one of these setups? just wondered what they may cost and if I have to have my ecu reprogrammed.

SHC,.....if your reading this, sorry I highjacked the thread....it hadn't been used for a while so I brought it back up. lol......

 

Snowman,like i was thinking,the Meritor is actually a Wabco system.
I have a Wabco 4S/3M but it is EBS not ABS(which is the next level)
Works brilliant,haul unbaffeled tankers(98 000 lbs gross) and in 4y never hand a flatspot on any tyre.

All off which doesn't help you
I would write down the partnumbers off the ABS you have ,write a nice email to Meritor (or Wabco,if Meritor doesn't respond) tell them what you want to achieve and ask them how to do it.
If their customerservice is worth anything,you will get a reply how to do it the correct way.
I have found that with unusual setups,it is better you know how to do it as most workshops will have not a clue how to go about it.

 

I agree Daf. Sad thing is, the more I investigate the ABS situation, the more it looks like I am gonna have to take it to a dealer with meritor/wabco TOOLBOX software program and actually have the lift axle configuration inside the ECU on my abs module turned ON. which sucks because I liked Autocar and some of the other self engineerd designs I have seen. That's what I was gonna do, but it looks like its not gonna be that simple unless I just don't worry about the abs functioning properly, which I wont do. I don't wanna take the chance of skidding a set of duals, dot, ect ect.......

I'm going to do what you said. I'm just gonna send an e-mail over and see what I can find out. most( if not all the dealers) I have delt with just never seems very helpful in a situation like this unless you let them do all the work at a major expense or extreme time delay waiting on them to get the trailer done. so dealing with the manufac is possibly the best way.....

i'll keep ya posted on what I find out.

 

also, I found that Hendrickson makes a nice kit for the drop deck suspensions. I have a the ht 250 us under mine, its underslung so clearance is gonna be an issue if I make my own, but I kinda liked this one. it called the SBL-250US

for anyone thinking about a lift axle on a step, this looks to be a decent and easy to install setup. http://www.hendrickson-intl.com/CMSPages/GetFile.aspx?guid=dc125c8e-0cd2-462d-b383-21d0b1048ba3

 

Can someone tell me the difference between a dump axle and lift axle? I mean the name says it all but what does the lift axle do that the dump doesn't, or visa versa? I am pretty sure I know already but, if that is true, sounds like just dumping air out of the air bags on rear axle would still allow the tires to drag... When I drove for TMC I am pretty sure they had a dump valve on rear axle, initiated from the cab but I never realized the axle didn't actually lift, I knew it didn't lift that far but, I thought it did lift.

 

A dump simply lets all the air out of the bags allowing the tires of that axle to gently scuff as they get dragged. A lift axle dumps the bags and then has a set of smaller bags that inflate to lift the axle off the ground.
A dump is simply an air valve.