ABS Brakes

[Forever Fendt]

I am slowly getting components together for a trailer build it will be carrying about 15 tons we will be fitting air brakes This will be a huge step forward as we have only had hydraulic before I was wondering is it worth going to the expense of adding ABS This will add about £500 to the build cost any thoughts welcome

 

[Zebbedee]

From a safety point of view very little to be gained properly working brakes are more than capable

 

[Mursal]

Probably not, though you might find it hard to stop then locking up when empty.

 

[Chae1]

Fit a load sensing valve. We've one with abs and one without. Don't notice any difference. Run one with abs on fastrac to keep us legal at higher speeds.

 

[Andrew]

Fit a load sensing valve. We've one with abs and one without. Don't notice any difference. Run one with abs on fastrac to keep us legal at higher speeds.

Fit a load sensing valve to the air and make sure the chambers meet the 50% efficiency required. If you are fitting combined air / oil brakes note the air side may be 50% but the hydraulics will normally be 25% so not worth fitting an LSV.

Fit the ABS sensors, and somewhere to mount the ABS valve, then you can add it cheaply and easily in the future if you decide you need / want it.

 

[Chae1]

Fit a load sensing valve to the air and make sure the chambers meet the 50% efficiency required. If you are fitting combined air / oil brakes note the air side may be 50% but the hydraulics will normally be 25% so not worth fitting an LSV.

Fit the ABS sensors, and somewhere to mount the ABS valve, then you can add it cheaply and easily in the future if you decide you need / want it.

I once had a bit of a accident when lsv not working on a air/hydraulic system. So i shall disagree that its not worth fitting.

Servicing trailers this week and this one broken, and will be fixed.

 

[Andrew]

I once had a bit of a accident when lsv not working on a air/hydraulic system. So i shall disagree that its not worth fitting.

Servicing trailers this week and this one broken, and will be fixed.

I'm not saying it's not worth fitting - in fact if you have the properly specced actuators to achieve the 50% efficiency then it's essential otherwise the wheels will lock as soon as you touch the brakes when empty. LSV should be fitted if you have ABS as well, otherwise the ABS will be working overtime when empty in all conditions, rather than just when necessary.

What I am saying is that most combined air / oil actuators supply different forces. The air side will most likely supply 50% efficiency (and therefore essential to fit LSV) but if you use the oil actuators they normally only supply 25% braking efficiency, and a hydraulic LSV is therefore not essential, as the wheels are less likely to lock when empty.

 

[Forever Fendt]

Fit a load sensing valve to the air and make sure the chambers meet the 50% efficiency required. If you are fitting combined air / oil brakes note the air side may be 50% but the hydraulics will normally be 25% so not worth fitting an LSV.

Fit the ABS sensors, and somewhere to mount the ABS valve, then you can add it cheaply and easily in the future if you decide you need / want it.

The air over hydraulic brake kit comes with load sensing valve as standard and the a BS valve is extra the brakes will be full spec commercial with 420 x 180 Brake shoes and the supplier has offered to do brake calculations if I supply the relevant information

 

[Andrew]

The air over hydraulic brake kit comes with load sensing valve as standard and the a BS valve is extra the brakes will be full spec commercial with 420 x 180 Brake shoes and the supplier has offered to do brake calculations if I supply the relevant information

I'm willing to bet it comes with an air LSV but not an oil LSV for the reasons I've mentioned. Unless you are pulling the trailer with a Fastrac or Unimog I wouldn't fit the ABS valve, but would definitely fit the axle sensors and bracketry.

 

[Blue.]

I wouldn't bother with hydraulic just have it on air.

 

[Forever Fendt]

I wouldn't bother with hydraulic just have it on air.

I am sorry you can’t borrow my trailer as it’s only got airbrakes in your tractor doesn’t have airbrakes

 

[Forever Fendt]

I'm willing to bet it comes with an air LSV but not an oil LSV for the reasons I've mentioned. Unless you are pulling the trailer with a Fastrac or Unimog I wouldn't fit the ABS valve, but would definitely fit the axle sensors and bracketry.

Well you have won the bet I didn’t make it clear but yes it’s only a load sensing valve on the air the supplier said it would not be worth fitting one on the hydraulics as you stated

 

[Forever Fendt]

It looks like I have my answer now one other question manual or automatic slack adjusters

 

[Blue.]

I am sorry you can’t borrow my trailer as it’s only got airbrakes in your tractor doesn’t have airbrakes

Fit palm fittings,that should stop most that have air,well except me.☺

 

[Andrew]

It looks like I have my answer now one other question manual or automatic slack adjusters

Manual.

 

[Matt L]

For what little or costs to have ABS I would fit it. A haldex unit is easily fitted and works very well. Really does shorten the stopping distance when braking hard.

 

[d williams]

I am sorry you can’t borrow my trailer as it’s only got airbrakes in your tractor doesn’t have airbrakes

and a spoon hitch??

 

[TripleSix]

I don't see the point in ABS on tractor trailers.

They don't go fast enough to get out of shape when braking hard.

 

[Matt L]

No but you can still lock the tyres, burning out your expensive rubber and having something sliding along behind you.

 

[Zebbedee]

No but you can still lock the tyres, burning out your expensive rubber and having something sliding along behind you.

Yes but the abs fitted to trailers is not like a car on any I have seen it is actually only got sensors on one axle so fairly pointless however if you want proper load sensing brakes go air suspension brakes are linked to air bag pressure and absolutely brilliant ??