Fifty Millimetre Towball in Powder Coated Steel

The part that takes the load: the standard bolt on ball for a flange bar, forged rather than cast, which is the difference that matters and is never on the label.

Towing is the one thing you can buy for a car where the wrong part is not merely disappointing. Every towbar listing here states the type approval number, the D value, the maximum noseweight and whether the bumper has to be cut, because those four facts decide whether a bar is legal on your vehicle and whether it will pull what you want to pull. Every electrical listing says plainly whether it is a dedicated loom or a universal one with a bypass relay, and what each will and will not do. We would rather lose a sale to a cheaper part than sell you one that does not fit.

Specification

• Fits: any 83mm flange towbar unless stated otherwise. A swan neck has an integral ball and takes none of these
• Approval: UNECE R55 where the part is load bearing, with the rating stamped on the shank. A ball without a stamped rating is not a bargain
• Rating: 3500kg gross, 100kg noseweight
• D value: 17.0 kN on the load bearing parts, which is above any car application. The D value is the measure of how hard a towbar can be pulled. It is worked out from the towing vehicle's maximum mass and the trailer's maximum mass together, in kilonewtons, and the bar's D value has to be equal to or greater than the figure your combination produces. We publish it on every bar and there is a calculator linked from every towbar page.
• Noseweight: 100kg. Noseweight is the downward load the trailer puts on the ball, and the figure you may use is the lowest of four numbers: the towbar's S value, the vehicle handbook's noseweight limit, the towball's rating and the caravan coupling's rating. Most people know the first and none of the other three, and a combination that is legal on paper is often over the limit on the one that matters.
• Ball height: 350 to 420mm laden once fitted, and a drop plate is how you get there if the vehicle sits high
• Electrics: not applicable unless the part carries a socket plate
• Fitting time: fifteen minutes with a torque wrench, and the torque figure matters: a towball bolt tightened by feel is either loose or stretched
• Bumper: check the ball clears the bumper before you tow. A protector is a few pounds and a respray is not
• Materials: a chromate primed and powder coated S355 steel weldment, which is the standard finish and will last the life of most cars. Forged rather than cast, which is the difference between a ball that deforms and one that cracks
• Weight: approximately 1.4 kilograms
• Guarantee: five years
• Stamping: the rating and the approval number are stamped on the shank. If you cannot read them on a part you already own, it is time to replace it
• Wear: a towball wears to an egg shape and a coupling wears to match. A 50mm ball worn below 49mm should be replaced, and a gauge costs about nine pounds
• Grease: grease the ball unless you run a friction stabiliser, in which case the ball must be clean and dry. A friction stabiliser works by clamping pads onto the towball, so the ball must be clean, unpainted and completely free of grease. A greased ball with a stabiliser on it is doing nothing, and it is the commonest fault we see on a caravan that snakes.
• Torque: stated in the instructions, and worth a torque wrench

What arrives

• the item
• bolts, nuts and washers where applicable
• a torque figure card
• instructions

Fitting

Fifteen minutes. Use a torque wrench and the figure on the card, and check the bolts again after the first hundred miles, which nobody does and everybody should.

Before you order

Two things separate a good towball from a cheap one and neither is visible. The first is forged against cast: a forged ball deforms slowly and a cast one cracks. The second is the stamping, because the rating and the approval number on the shank are what an inspector, an insurer or a buyer will look for. Everything here is forged and stamped, and a ball that is neither is not worth the eight pounds it saves.