UN R55 Base text (03 series) · UNECE Regulation No. 55 (ECE R55) — Uniform provisions concerning the approval of mechanical coupling components of combinations of vehicles.
UN R55 — 03 series of amendments
Changes from 02 series of amendments (supplement 2)
- What changed
- In Annex 7, paragraphs 1.4. to 1.4.2. now refer to coupling devices instead of drawbar eyes.
- New text in Annex 7 says that the support device requirement does not apply “in the case of trailers designed for special operations where they are normally only separated in a workshop (i.e. Class T couplings) or when loading and unloading in specifically designed operating areas”.
- New paragraphs 13.6. to 13.10. give transitional provisions for the 03 series of amendments.
- Why
- Paragraph 1.4. of Annex 7 referred only to “drawbar eyes”, but typical centre axle trailers come with different types of coupling devices.
- The need for a support device adjustable in height must not depend on the type of coupling device.
- A new series with transitional provisions is proposed because centre axle trailers without a support device may be on the market.
Q1What changed14 changes
Support device for drawbars of centre axle trailers (Annex 7, para. 1.4.1.)
Drawbars for centre axle trailers must have a support device which is adjustable in height “if the bearing mass at the coupling device on the trailer exceeds 50 kg, when the trailer is uniformly loaded to its technically permissible maximum mass”. Before the 03 series, the text said “drawbar eye” instead of “coupling device”. The 50 kg limit and the loading condition do not change. A new sentence after this requirement says: “This requirement shall not apply in the case of trailers designed for special operations where they are normally only separated in a workshop (i.e. Class T couplings) or when loading and unloading in specifically designed operating areas.”
Coupling devices instead of drawbar eyes (Annex 7, paras. 1.4. and 1.4.2.)
Paragraph 1.4. of Annex 7 now reads “Attachment of coupling devices and drawbars on trailers”. Paragraph 1.4.2. now starts “When attaching coupling device and drawbar” instead of “When attaching drawbar eyes and drawbar”. The rest of paragraph 1.4.2., on the device for axle load sharing, does not change.
Transitional provisions for the 03 series of amendments (paras. 13.6. to 13.10.)
From the 03 series' official date of entry into force, no Contracting Party applying this Regulation may “refuse to grant or refuse to accept” 03 series type approvals (para. 13.6.). As from 1 September 2025, Contracting Parties applying this Regulation are not obliged to accept type approvals issued to the preceding series (para. 13.7.). Notwithstanding paragraph 13.7., Contracting Parties applying this Regulation must continue to accept preceding-series type approvals of mechanical coupling devices and components (para. 13.8.). Notwithstanding paragraph 13.7., Contracting Parties applying this Regulation must continue to accept preceding-series approvals for vehicles not affected by the 03 series changes (para. 13.9.). Contracting Parties applying this Regulation must not refuse to grant type approvals according to any preceding series or extensions of them (para. 13.10.).
Example of an arrangement of the approval mark (Annex 3)
In Annex 3, the text that explains the example approval mark now says “meeting the requirements of the 03 series of amendments to this Regulation”. Before, it said “01 series of amendments”. The figure of the example approval mark also changes.
RegVault numbers 13.11. and 13.12. for the earlier paragraphs 13.6. and 13.7.
In this text, the paragraphs numbered 13.6. and 13.7. before the 03 series of amendments have the numbers 13.11. and 13.12. A RegVault Note explains that the 03 series inserted new paragraphs 13.6. to 13.10. without renumbering the earlier ones. RegVault renumbered them to avoid duplicate numbers. This renumbering is not part of the official text, and the wording of these paragraphs does not change.
Q2Why it changed
- Proposed by
- Experts from Austria and the Netherlands
- Working party
- GRSG, 126th session (October 2023)
Reasons
The proposal clarifies the need to have a support device for centre axle trailers, independent of the type of coupling device.
Source
“It clarifies the need to have a support device for centre axle trailers, independent of the type of coupling device.”
Paragraph 1.4. of Annex 7 referred only to “drawbar eyes”. Typical centre axle trailers come with different types of coupling devices, for example Class D or Class B.
Source
“It was noticed that paragraph 1.4 of Annex 7 only refers to "drawbar eyes", whereas typical centre axle trailers come with different types of coupling devices, e.g. Class D or Class B.”
The need for a support device adjustable in height must not depend on the type of coupling device. For the user, it takes the same effort to connect a centre axle trailer with a towing eye or, for example, a coupling head.
Sources (2)
“The necessity to have a support device adjustable in height shall not depend on the type of coupling device”
“for the user, it will require the same effort to connect a centre axle trailer equipped with a towing eye or e.g. a coupling head.”
Most Contracting Parties and their Technical Services involved generally understood that a support device was also required for coupling devices other than drawbar eyes. At the Type Approval Authority Meeting of May 2023, not all attendees shared the same opinion.
Sources (2)
“It has been the general understanding for most of the contracting parties and their Technical Services involved that a support device was also required for other types of coupling devices than just drawbar eyes.”
“It was noticed though while discussing this subject in the Type Approval Authority Meeting of May 2023, that not all attendees shared the same opinion.”
It may happen that centre axle trailers without a support device are on the market. A new series of amendments with transitional provisions is proposed to solve this.
Source
“Therefore, it may happen that centre axle trailers are available on the market without support device, which is why a new series of amendments including transitional provisions is proposed to solve this.”
Document trail
- 2023-07ProposalECE/TRANS/WP.29/GRSG/2023/18Proposal by experts from Austria and the Netherlands
- —RevisedGRSG-126-19-Rev.1Revised proposal by experts from Austria and the Netherlands
- —Working party adoptsECE/TRANS/WP.29/GRSG/105GRSG session report, para. 17
- 2023-12Sent to WP.29ECE/TRANS/WP.29/2024/15Text that GRSG sent to WP.29 and AC.1
- 2024-03WP.29 adoptsECE/TRANS/WP.29/1177Adopted at the 192nd session (session report, para. 140)
- 2024-09-22In forceC.N.408.2024.TREATIES-XI.B.16.55UN depositary notification
Q3Who is affected
Vehicle manufacturer
- Check your centre axle trailers against Annex 7, paragraphs 1.4.1. and 1.4.2., which now refer to the coupling device.
- Check paragraphs 13.7. to 13.9. for the acceptance of your preceding-series approvals as from 1 September 2025.
Component supplier
- No direct action for this role.
Technical service / Approval authority
- Check that centre axle trailers with a coupling device other than a drawbar eye meet Annex 7, paragraph 1.4.1.
- Be ready for 03 series type approvals from the 03 series' official date of entry into force (para. 13.6.).
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ⓘ This report gives advice only. It is not legal or type-approval advice.