I need some advise from the experienced. We are touring Namibie with a Tourer SW. The van started bumping into the car when I brake and similar when I accelerate after braking. Do I only need to adjust the brakes or is there something else that I’m unaware off?

Chris, I hope somebody can give you 'expert' advice soon.

I do not think this has anything to do with wrongly adjusted brakes. It sounds as if the shock absorber which is part of the tow hitch, is busted.  This is a component that exerts resistance against the momentum of the caravan moving forward when the tow car brakes in order to engage the brakes on the caravan smoothly, differently from what you are experiencing.  By the caravan pushing on the tow hitch when the tow vehicle's brakes are applied, the van's brakes are engaged. The van's brakes are  operated by a solid bar attached to the tow hitch. It also smooths the release of the caravan's brakes so that you do not experience the small shock when you start driving off

It also contains a mechanism that pushes the hitch forward if no pressure is applied due to the tow vehicle braking, thereby releasing the brakes when the caravan is not attached to the tow vehicle. .  This shock absorber needs to be the correct specified one according to the weight of the van, so do not consider choosing a heavier one as this will have the effect of reducing the braking ability of the van and putting more stress on the tow vehicle's brakes.

It is reasonably easy to replace the unit yourself if you are mechanically minded and have the necessary tools, otherwise get it fitted by a caravan workshop or perhaps a vehicle workshop of engineering firm if you are able to obtain the spare part.  The problem is not serious or threatening so if you have problems getting a new unit, just endure the bit of discomfort until it can be fixed.  Just inspect the hitch to see of anything seem to be loose or broken which I don't thing will be the case.

Mine did that after Discovery caravans adjusted the brakes. I replaced the shock and it still does the same. One stop caravan clinic adjusted my brakes previously and my caravan did not do that. I will take it back to them.

My conclusion is brakes adjustment.

Thanks for the advise. I am inWindhoek untill tomorrow and will seek a caravan shop in the morning

Also adjusting the brakes is much cheaper than replacing the shock. The shock cost me R1250.

It might be your vehicle towbar male ball that is worn out.

It should measure - 50mm on OD.

If not, then it might be: Inspect the ID of the caravan's mechanism.

The difference between male and female must not be more than 5mm on OD and ID.

i.e: - Difference between male and female towing mechanisms should be within specs:-

- Towbar Ball = 50mm on OD.

- Female mechanism on Van should not measure more than 5mm on ID.

I might be wrong on the female measuring ID size, but I had the same problem with an U/size towbar male ball.

Anonymous wrote:

It might be your vehicle towbar male ball that is worn out.

It should measure - 50mm on OD.

If not, then it might be: Inspect the ID of the caravan's mechanism.

The difference between male and female must not be more than 5mm on OD and ID.

i.e: - Difference between male and female towing mechanisms should be within specs:-

- Towbar Ball = 50mm on OD.

- Female mechanism on Van should not measure more than 5mm on ID.

I might be wrong on the female measuring ID size, but I had the same problem with an U/size towbar male ball.

If the Male towball measure within specs of 50mm OD by measuring with a Vernier or Micrometer, hitch the caravan and measure the Female ID with a Feeler Gauge.

The clearance between Male and Female should not measure more than 2,5mm/side.

I inspected the mechanism and I think Fred is correct. I can push the caravan mechanism in and out by hand. ( handbrake on)

Sal shock damper wees. Soms is dit net die skroef wat hom in plek hou, uit. Dis darem nie n baie duur oefening nie... sou jy moet vervang 

Relaxed Camper wrote:

Sal shock damper wees. Soms is dit net die skroef wat hom in plek hou, uit. Dis darem nie n baie duur oefening nie... sou jy moet vervang 

Myne was nie. Die oorloop remme het te veel speeling.

Daai speling tussen die "Shaft "wat terug druk van die hak ,en die hammer moet 8 tot 10 mm wees ,as dit  baie meer  is ,sal hy stamp,want dan werk jou remme nie ,of werk telaat .Hy moet ook nie teklein wees dan kan jou remme ook warm word .Onthou net dit is belangrik as jy daai gaping regstel moet jy jou remme weer stel .Ek stel al vir 42 jaar al my karavane se remme self, en het nognooit probleme gehad ,maar as jy nie weet hoe ,kry iemand wat weet ,anders gaan jy langs die pad staan .As jou karavaanhak se shock so is, dat jy hom in en uit druk met die hand, is hy beslis klaar en moet vervang word .

You can test what is wrong yourself as it can be a combination of things.  Check the following:

When the caravan is parked go to the tow coupler and push against it as if you would be applying the brakes.  You should be able to push the tow rod in but with much difficulty and very very slow.  The damper allows that the brakes of the caravan is applied slowly NOT SUDDENLY.  So as you brake the caravan runs in, the tow rod is pushed in against the resistance of the damper and at the same time the caravan is applying the brakes thus the action of pushing the tow rod in is reduced.

When you are towing the caravan normally there should not be a bump during braking and again one during pulling away.  The fact that your caravan does this clearly indicates that the damper has seen its life use.

In my explanation above you will see that it is important that the brakes are adjusted correctly because that in essence prolong the life of the damper in such a way that the brakes are gradually applied also reducing the run in distance of the damper in a specific brake scenario.

So I can tell you now that you will need to replace the damper and then adjust the brakes correctly.

I can forward you the process to adjust the brakes as it is done with a flat tip screwdriver.  I have been doing it myself since I had a Jeep on a VW Beetle chassis and I bought my first caravan.

Fred, jou diagnose was “spot on”. Die shock damper was vervang en die gestampery is weg. Dit is n bleddie duur skokbrekertjie daai.

Baie dankie

Ons probeer almal maar mekaar help uit ons ondervinding. Bly dit kon jou help.

Bly jou probleem is opgelos. Die skokbreeker vervang het nie myne opgelos nie.

Alfred reken dit kan ook rem versteling wees as ook rubber dempers op die over run?

Ek het die rem stelsel na gegaan volgens Al-Ko (Jurgens) se Owners manual. Die volgende probleeme is ontdek:

1) Die rem kabels op die cross member was skeef gestel. Dit beteeken die een kant (wiele regs) rem meer as die ander kant (wiele lings).

2) Die regter agter wiel se rem skoene het weg geslyt (metal on metal).  Die regter voorste wiel se rem skoene was nog sigbaar. Die linker rem skoene was die beste maar ook op hulle einde.

Ek het die kabels oor gestel soos beskryf in die Al-Ko proseduure en all vier wiele se skoene se velling laat oor voer en al vier die dromme laat skiem.

My woonwa was in Januarie (2000Km terug) deur Discovery Caravans in Waterkloof Rif gediens?

Die wiel laers is nog goed en ek het hulle net weer gegries. Die ou gries was nog soos nuut.

Metal on metal

I have just test towed the caravan.

The over run bumping into the car is now gone and the caravan brakes smoothly and very effectively.

The brakes were incorrectly adjusted and worn so...... that was my problem. Not the shock.