Chug-a-chug whilst towing.

[terryc]

We have been away with the old dunny on wheels 6x4 box trailer loaded up and each time/trip, it chugs a little or a lot.

It isn't the ball being loose in the cup as I've checked that, but there is play in the ball holder in the tow bar receiver hitch.

Do I need to look at shimming it to stop this?

Another thought that occurred to me is that I might be just balancing the trailer too well from front to back and not putting enough weight on the ball. Everything is contained within the 6x4 box and most times it is still possible for me to lift the front.

 

[KraftyPg]

Being able to lift from the drawbar isn't a sure sign that your loading correctly, if you can't lift the drawbar when loaded it's a fair sign it's not well loaded likewise if it comes up too easily but you could still have your weight loaded unevenly or even have the axle in the wrong location for the loads you carry and be able to lift the drawbar. I'd be checking the play in the hitch before anything else though.

 

[WoodyD40]

Number of things to look at:

How loose is the hitch on the car ... (i've found most of the noise i get is from the hitch as i'ts usually only fixed with the pin, as i cant be arsed doing up the lock nut underneath).

Might sound silly, but check the tow ball is REALLY secure - i've seen one mate who nearly lost his 4.5m boat because the tow ball come loose!

I usally grease the tow ball, and up inside of the trailer hitch as well - stops some of the grating sounds when turning. Also will help reduce the friction that 'can' cause a tow ball to work its way loose.

If the trailer drops nicely onto the tow ball (when loaded) then you have enough weight on the front of the trailer - you should be able to lift the trailer (with a bit of a struggle) usually for a 6x4.
If you can lift it off (loaded) really easy, then you probably should put more weight on the front.

anyhow, thats my 2 bobs worth.

 

[Old.Tony]

You're supposed to have about 10% of the trailer's weight on the ball. 600Kg of trailer means 60Kg on the ball - measuring it by using bathroom scales under the jockey wheel is a close enough guide.

As the others have said, I'd check the tow ball to make sure it's really, really tight. I'd also check the free play of the hitch on the ball - there shouldn't be a lot - and make sure the hitch is firmly anchored to the trailer frame as well. Making sure the towball mount is secure is also important - what if you've got a loose bolt underneath?

 

[terryc]

The ball is tight and greased.

Hmm, seems like the genuine nissan towbar I have doesn't have that lock nut underneath to take play out of the receiver hitch. will have to look into that.

It just comes as a bit of a shock after thousands of Kms on the old van with not a murmur.

It is something I'm going to have to get sorted as our intended "new" CT is just under the ton.

 

[Old.Tony]

I don't bother with the hitch lock nut (that secures the 50mm square insert in the vehicle's receiver). The load leveler that I use probably prevents that from making any noise anyway, as it twists the hitch upwards at the rear.

I'm more concerned about the bolts/nuts that retain the vehicle's receiver in the vehicle. By "underneath", I am referring to right underneath, the bolts that hold the hitch itself to the chassis of the vehicle.

A couple of those not quite as tight as they need to be will give you the rattles, and could spell disaster for the chassis if left loose with a load behind as it will have the opportunity to bend around the remaining bolts in the chassis.