6.6 Towbars
Information
This inspection applies to: all types of towbar fitted to the rear of a vehicle. It does not include emergency towing eyes.
Tow ball covers must not be removed to facilitate inspection of the tow ball. Some tow bars are hidden behind an access panel in the bumper or bodywork. Unless requiring the use of tools or specialist equipment, these panels must be removed to facilitate the inspection of towbar components, as well as checking inside the luggage compartment, including lifting of loose fitting mats or carpet.
Retractable towbars should be tested in their inuse position unless this requires the use of tools or specialist equipment. If a tow ball or pin is not fitted at the time of test, e.g. because it is detachable, has been unbolted or otherwise removed, but the attachment brackets are still in place, these brackets should still be assessed unless they have been deliberately rendered unfit for further use. There may be play in some detachable tow balls between the receiver socket and the tapered swan neck fitting, with up to 3mm movement measured at the ball end. Reason for Rejection 4a should only be used where play is greater than this. Quick release mechanisms must not be operated, only visually assessed.
Wear in a pin, jaw or hook should be regarded as excessive if the thickness of the metal at any point is reduced by more than 25% of the original thickness. Pin locating holes should be rejected if they are worn or elongated by more than 25% of their original diameter. These criteria also apply to pins and brackets for any height adjustment or swivel devices. For tow balls the amount of acceptable wear is considerably less. However, a tow ball should only be rejected if a visual assessment indicates that the tow ball is obviously excessively worn. Many bolt-on type tow balls have accessory devices sandwiched between the tow ball and its mounting flange. These are not to be considered as inappropriate modifications unless their fitment is clearly likely to adversely affect the roadworthiness of the vehicle/trailer combination. Trailer electrical couplings are tested under Section 1.9.
Method of Inspection
1. Visually assess the towbar for wear and pull on the towbar and/or its mountings to check for security, corrosion, fractures or damage.
2. Check the towbar assembly is attached to the vehicle structure using mountings, supports and fixings of an appropriate size and type.
3. Check the presence and security of:
a. retaining devices e.g. nuts bolts b. locking devices e.g. split pins, R pins.
Note: It is not always possible to determine the presence and effectiveness of certain types of locking devices eg locking fluid or nyloc nuts.
4. On detachable tow balls:
a. check for play between the tow ball arm and its receiver socket
b. visually assess the condition of any quick release mechanism.
5. On height adjustable or swivelling towbars, check:
a. for presence, and security of locating or swivel pins
b. locating or swivel pins and brackets for excessive play or wear
c. locating or swivel pin retaining devices for presence and security.
6. Check the condition of the body and chassis in the vicinity of the towbar mountings.
7. Check the towbar assembly for any inappropriate repair or modification.
Reason for Rejection
1. A towbar component insecure, fractured or e xcessively:
worn
corroded, or
damaged.
2. Towbar assembly is attached to the vehicle structure using a mounting, support or fixing which is obviously of an inappropriate size or type.
3.
a. Retaining device missing or insecure
b. locking device missing, insecure, inadequate or damaged to the extent that its operation is impaired.
4.
a. Excessive play between a detachable tow ball and its receiver socket
b. a quick release mechanism that does not secure the tow ball arm as intended.
5.
a. A locating or swivel pin missing or insecure
b. excessive play or wear in a locating or swivel pin or bracket
c. a locating or swivel pin retaining device missing or insecure.
6. Any deliberate modification, excessive corrosion, damage, fracture or inadequate repair of a load bearing structure or supporting panelling within 30cm of the towbar mountings, which affects its strength to the extent that the security of attachment of the towbar is significantly reduced.
7. A towbar assembly inappropriately repaired or modified such that it is likely to adversely affect the roadworthiness of the vehicle/trailer combination.
Not sure how you would go on with the legalities nowadays because a lot of towbars are only marked with stickers or ally riveted plates that fall off intime, I know I fitted a virt new second hand dixon bate towbar to my passat and there was no numbers on it, so if it was properly made who could tell??.
have alook round some breaker yards and many of the bars on old cars have no numbers
I for one, when testing would only look at the quality of the tow bar and its various bits to be honest, and some of the 'proper' made items look shocking. Using half the size bolts than I would in some points.
Hi just a thought on tow bar legalities here is one I fitted to a vw transporter last week note the sticker on the bar that is all that tells anybody this is a legally tested towbar how long will that last? it is on the underside of the bar so will get scratched the first time a jack is used on it. and the paint will soon deteriate with the weather etc, the other sticker ia a paper one and is nothing to do with the legalities
the side plates went inside the chassis which was approx 1.75mm to 2mm section channel, with no washers on the 3 bolts per side or load spreading plates !!
obviously this has been tested but didnt look that strong to me to have 3 tonnes or more swinging around on it
PLUS the QR ball had two 6mm sprung loaded ball bearings which kept the adapter up in the socket of the X member and took the full nose weight of the trailer, that didnt look that strong either, against a properly bolted tow ball . I for one would not like to trust that system for very long in the harsh winter conditions etc
The point here is as said before, there are many like this in scrap yds etc that are re used, when the stickers are gone who is to say or prove that this bar was 'professionally' made?
I personally would have made bar this considerably stronger if I had been designing it.
I think that if the bar is strong and looks adequate for the job no person would bother question the legality of it given there are hundreds of different manufacturers, out there designing and making bars.
cant remember exactly but the transporters can tow 2.7 ton ish and usually 100kg nose but that goes up dramatically under extreme braking to-------- ??????