I have a DAF CF 85 that is 5 years old. It has an issue with the steering where it will go really heavy until I blip the throttle and it gets loose again, but it is doing it on a more regular basis. Apparantly its something to do with the airlines for the steering, but I cant locate the exact problem. Has anyone else had this issue and know what the fix is? Its a real pain when backing onto a bay down a slope as I cant blip the throttle lol. On normal road driving its workable, but it sticks a little bit.
Its not an major issue, I can drive easily and it works most of the time, it happens at random times. It just annoys the hell out of me. They have replaced the entire steering system and it hasnt fixed it. Powersteering fluid is ok. I have suggested the U Joint, but that would not clear up with the blip of the throttle.
I would say it is fluid related, since blipping the throttle would only increase the air in the tanks, and by such a small amount as to be negligible. Only a guess though.
Had same problem with an FH12 once where the steering would suddenly go rock hard and impossible to turn at a standstill. Turned out to be an air block in the power steering fluid system. Was fine once bled.
I would jack the truck up under the front chassis so that both steer wheels were off of the ground and then spend 10 minutes spinning the steering wheel from lock-to-lock and checking the fluid levels, this sounds like air in the hydraulics.
if it frees up when you blip the throttle its almost certainly fluid related…todays p/s pumps are gear driven mostly not belt driven…so belt tension should not be an issue.
air in the system is the most likely cause…or a faulty pump thats not delivering enough pressure at low revs.
if you cant turn the stering wheel freely at ALL times vor it!!
Make sure if you bleed it up to jack the front up first, when i worked for a main dealer years ago they reccomended you knock the draglink off the drop arm on the steering box so you got maximum travel when you turn it lock to lock
I think you will find its the steering box,friend of mine had the same type of thing on a Foden [same box],he had it rebuilt and it cured it. My Foden also has a similar problem,some times it just has a dead spot on the power steering. Mark
It’s the pump or steering box and it’s low pressure that’s causing it, building up the air until the tanks burst will have no effect whatsoever as there is no air in the power steering system, or there shouldn’t be
As for this :-
Its not an major issue, I can drive easily and it works most of the time, it happens at random times. It just annoys the hell out of me. They have replaced the entire steering system and it hasnt fixed it. Powersteering fluid is ok. I have suggested the U Joint, but that would not clear up with the blip of the throttle.
[zb]ing hell, are you for real, what happens if ‘random’ means you end up with the steering locking as you turn into a road and end up mounting the kerb and running people over, or you can’t make it around a bend and have a head on collision
This lorry should be parked until it’s fixed, no question
I would still replace the UJs on the column. Sometimes that blip can increase the pressure enough to knock it free. Driving it like you are is not safe and not wise.
I had the high pressure pipe from the pump to the box split yesterday in Calgary… You don’t realise how bad things are till it happens…
I think you are taking how bad the problem is too far, it only happens at crawling speed, not if I am doing anything faster than that. Basically only happens when I am manouvering slowly onto a bay or similar when the revs are low. So you can retract all your rolleyes thanks. I know when it will do it, and its not like the fitters have not tried to fix it! Its not affecting any other part of my driving.
Right Dogmatix, no it’s not being taken too far, what you are experiencing is either a UJ seizing or the pump not supplying enough pressure, neither will cure themselves, but they will get worse over time, at the moment it happens at manouvering speeds, as time goes on it’ll happen just when you don’t want it to, so it needs fixing now
Two things that should instantly VOR any vehicle are brake or steering problems, no excuses
Its been doing it since it for years and it has not got any worse…and despite the entire steering system being replaced it is still doing it…lets have that truck off the road for years then.
