Towing trouble?

[ethan1]

Had problem with trailer wobbling while at low speed and above 90km/hr while towing. Thought it was bearings, all replaced but still wobble. Moved axle forward as there was too much weight on towball. still wobble. Mate said tyres can get a flat spot when stored for too long. Makes sence, just wondering can tyres be fixed, as expensive exerecise if i buy new tyres and doesnt fix problem. when towing and looking back in side mirror , the whole wheel seems to be shaking up an down. will take to mechanic, just thought i'd ask if anyone has had same problems and any solutions.
Ethan

[Hamish73]

I'd just take the wheels off and take to a tyre shop. Their wheel balance machine should pick up any major problems.
I has a vibration in an old commodore that I thought was tailshaft, turned out to be a tyre

[disorderly]

I have had this happen, turned out to be quite a noticeable bulge in the tyre.
Replaced tyre and no more worries.

[Roughasguts]

Most tyre places won't bother with balancing your tyres on a trailer.
Don't know why, it's not like it takes a long time to balance them but maybe it's the little tab on the balance weight that gets hammered in under your rim, maybe that starts to rust and then your tyre will leak.

But anyway with your trailer how is the tow bar height if it's to high it will sway.

[2iar]

Just a suggestion before you go replacing any tyres - have you checked the pressures? I recently gave mine a good pump up and the 100 Km/h vibration has disappeared...

Good luck,
Mike

[Chimo]

Hi Ethan

I don't know what sort of boat or its weight but you can quickly determine if your problem is tyres by offloading your boat and taking your empty trailer for a run at the speeds you are having problems.

If it is tyres the problem will be magnified in the absence of the weight of your boat and so it was when I had a similar issue with mine.

You will know quite quickly if it is tyres separating, bulging and generally shot just by looking in your mirrors if it a subtle fault and if its a major problem the trailer misbehavior will be significantly worse even at lower speeds. The weight of the boat on the trailer tends to deaden the bounce I guess.

If the thing runs smooth when empty then your issue is something else.

Cheers
Chimo

[bigjimg]

sounds unlikely at first but u could have water in your tyres,when at speed this water can cause serious balance probs and is easy too ckeck just let all air out of tyre and break bead.if tubed disregard this.jimbo.... how can this happen i hear u ask well one example is when u pump up your tyres at the local servo and they don't drain their compressor you would be surprised how much water can come though the line.i won't go into other examples not enough time see ya...

[Flex]

Either weight distribution issue or it could be your axle has moves back/forward on one side.. are your springs fixed or movable?

usually its too much weight over the stern..

[tunaticer]

My guess will be one of two options from what I read.
Firstly it could be tyre condition, wear, hardness or BALANCE.
Secondly it could be your axle is not quite square with the tow point and your trailer is slightly crabbing behind your tow vehicle. At certain speeds this can be quite noticeable and or dangerous if it is bad enough. Easy way to check your axle alignment is to run a tape measure fron the nearest edge of the tyre to the centre of the tow hitch where the ball goes and check that on the other side too. These two measurements should be exactly the same. Tyres should be the same on boht sides also for this measurement to work, if not measure to the hubs.

My money would be most likely balance of your trailer wheels tho.

Jack.

[ethan1]

Took tyres off and have a bulge in both of them, one slightly bigger then the other. Boat is 4 yrs old, but only this last year has been stored outside. maybe the sun has effect on tyres?

[Roughasguts]

Mate they where probably second hand tyres before they even ended up on your trailer.
They might be closer to 15 years old. And for some reason a boat trailer tyre seems to crack and split and bubble, and a box trailer tyre doesn't, maybe salt emersion has something to do with that.

[phewy]

Had problem with trailer wobbling while at low speed and above 90km/hr while towing. Moved axle forward as there was too much weight on towball. still wobble.
Ethan

Most common cause for trailer sway is bad load distribution and too much weight towards the rear so moving the axle forward would probably make it worse. Weight on the towball is good...within limits of course. Remember the 10% rule, and look at the legal capabilities of car and specs of towbar. If you can easily lift the front of your average 4.5m or bigger boat/trailer, then chances are there's not enough weight there.

Have the ball weight measured, either by public weigh bridge or borrow a set of ball weight scales from your nearest caravan dealer/repairer. They should let you borrow one for a small deposit fee. Aim for 10% ball weight.

[ethan1]

thanks paul, struggled to lift trailer, was way over the 10% mark. Though Boat has always towed great on prado. Try to put as litte as poss in the boat when towing.Found both tyres to be shot one starting to come away. Wheels in tyre shop should be all sorted by tomorrow.
Thanks all for the info, another satisfied ausfish member.