Tow bar

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Introduction

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If your vehicle already has a tow bar, you are probably settled, but you might still find some interesting information in this article.

Having a tow bar installed provides several benefits, apart from the obvious role to tow a trailer.


Terminology

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It appears that the terminology and meanings regarding the tow bar and its elements vary significantly from one region of the world to another. Another cause of confusion are so many types of connecting elements for the tow bar. There are balls, hitches, hooks, jacks, prongs, necks, swans, etc.

Therefore, this chapter is just meant to establish the nomenclature for this particular article. It's impossible to cover all combinations and terminologies.


  • A tow bar is a transversely-mounted rail (typically hollow, but made of thick metal), which is mounted on vehicle's rear chassis rails (in factory-made mounting points on the chassis rails).
  • A tow neck is a short pipe or plate which is welded or bolted on to the center of the tow bar, and protrudes orthogonally to the tow bar itself. Some tow bars don't have this, instead the tow ball or tow hitch connects directly to the tow bar.
  • A tow ball is a non-hollow metal ball onto which you actually clamp the towed or carried object. Some tow balls are a single-piece with the tow neck and some bolt onto the tow neck. Some tow balls bolt on directly onto the tow bar.
  • A tow hitch is a hook to which you attach another object.


Notes on terms

  • Sometimes the term "tow bar" is applied to the entire assembly (tow bar + tow neck + tow ball / hitch), but sometimes it means strictly only the tow bar itself. It depends on the context.
  • Tow neck can be die-cast as a single piece together with the tow ball, or be a separate piece.
  • Some tow balls bolt on directly to the tow bar, without a tow neck.
  • Tow ball dimensions are defined by international standards.
  • Sometimes the term "tow ball" is applied to the entire "tow ball + tow neck" assembly (especially if they are die-cast as single piece).
  • The term "tow hitch" is sometimes used to actually refer to the "tow ball".
  • A single tow bar can usually have either a tow ball or a tow hitch attached at the same time, but not both. However, there are cases of combined "tow ball + tow hitch" elements.

This general Wikipedia article can explain all the complexity of the terms a bit better.


Types of tow bars

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There are several different general designs of tow bars for Jimnys.

They depend both on the region of the world and on the era when they were made (for example, Jimnys 2 have been in production from 1982 to 2004, and Jimnys 3 from 1998 to 2018).


The design differences concern primarily the design of the tow neck or tow ball section.


Some tow bars (primarily ones from 20th century) use fixed tow necks/balls - they are welded to the tow bar.

Most tow bars from 21st century use detachable tow necks (tow neck can be disconnected from the tow bar). The methods of (de)attaching the tow neck vary significantly (from having to use tools and spanners to having some various convenient "click-on" or "push-in" systems). This depends on the manufacturer.


The length of the tow neck varies significantly depending on the model of the tow bar, and this plays an important utility and safety role. Some tow necks are even significantly longer than the width of the spare tyre (they protrude under it). Read more about this below.


Tow hitch
  • This is a typical tow hitch sold in the UK.
  • The tow ball should not be left in place in normal driving as it obscures the number plate.



Some pictures of Jimnys 3 with very long tow balls (all from continental Europe):


Suzuki Jimny 3 with EURO style tow bar



Benefits, issues and risks

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Benefits

  1. You can tow a trailer (obviously).
  2. You can carry a bicycle carrier.
  3. You can carry a cargo box - typical use is to transport hunting dog(s).
  4. Tow bar weights approx 15 - 20 kg, so it adds beneficial weight on any Jimny's rear axle, slightly decreasing vehicle's tendency to slide in bends and to wheel slip in 2WD mode on wet tarmac.
  5. When off-roading, if you exceed vehicle's departure angle, the tow bar is most likely to impact the ground before the rear bumper or other vulnerable body parts. It is much better to hit the tow bar than anything else in the rear. Tow bars can take a beating.
  6. You can weld on a pair DIY "recovery" points between the tow bar and vehicle's rear left and right factory tow points. When combined, those should provide good anchorage. Then you can attach shackles on those points for recovering the stuck vehicle.
  7. Having a tow bar fitted makes your vehicle appear more serious (if that turns you on).


Note Icon.pngFor additional details on above benefits, see wiki articles "Bicycle carriers", "Cargo space expansion and management" and "Recovery points".



There are no technical disadvantages of having a tow bar, except possibly a minor increase of fuel consumption because of added weight.


Legal issues

In some regions of the world, like some European Union countries, there could be various legal restrictions on using the tow bars.


  1. You might not be permitted to have a tow neck + tow ball attached to the tow bar when you are not towing a trailer or carrying a bicycle carrier (that is why detachable tow neck designs primarily exist).
  2. It might pose a legal issue if the tow neck + tow ball protrudes further than the spare tyre.
  3. Installing a tow bar on a vehicle "afterwards" (after the vehicle was sold as new from a saloon without the tow bar) might require some vehicle recertification in some countries, even if it is a OEM tow bar.


There are two reasons why a certain country might prohibit the presence of a tow ball / hitch on a tow bar while it is not used:

  • It presents a hazard for the vehicles trailing you in case of rear-end collision with your vehicle;
  • If it obscures the number plate (this is the case with all Jimnys with most tow ball designs);

In some countries neither reason is important, while in some both reasons are eliminatory.


For example, in United Kingdom, using standard tow bars (including those supplied by Suzuki!) with the tow ball attached without a trailer can be illegal, as the tow ball obscures the number plate. A lot of MOT inspectors let this go, but enforcement is getting more widespread now.


Risks

  1. If a vehicle rams you from behind while your tow neck is fitted, that vehicle might sustain nasty damage to its front end, especially if your tow neck is longer than the width of your spare tyre.
  2. If you reverse in a parking lot for example with the tow neck fitted, you need to be more careful not to hit another vehicle with it.


Warning Icon.pngNEVER attach a rope or strap to a tow ball or tow neck when recovering a stuck vehicle or when someone is recovering your stuck vehicle !!!
Although it might seem like a logical attachment point when recovering, tow balls and tow necks are not designed to endure shock loads which can be enormous when recovering a stuck vehicle. If a tow ball or tow neck breaks off under load, it becomes a lethal flying missile.
Broken off tow balls have destroyed other vehicles and killed people in spectacular manners!
You certainly do not want to participate in such a spectacle!



Buying a tow bar

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The best place to buy a tow bar would be from a dead Jimny in a vehicle junkyard.

You can of course buy a new OEM tow bar from Suzuki or from an aftermarket manufacturer, but expect a very high price.

Note Icon.pngThe wiki article "Accessories for Jimny (genuine Suzuki)" contains info on OEM tow bars and related accessories (like wiring etc.) (look under the section "Tow bars")


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There are many aftermarket manufacturers of tow bars, and some of them make suitable models for Jimnys. An example is Westfalia.


Manufacturing a custom tow bar

In certain regions of the world, there are workshops which manufacture custom tow bars. It is usually some generic design adopted to a particular vehicle. They usually also supply some certificate along with the manufactured tow bar.


If you can not obtain a genuine or afermarket made tow bar which was specifically made for your Jimny generation, taking your vehicle to such a workshop to have this "generic" tow bar customized for it might also be a practical solution.


Tow bar installation

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  • The procedure of installing a tow bar is a relatively simple bolt on job.
  • No fabrication is required, just a few wrenches and sockets for bolts.
  • A genuine new Suzuki tow bar will even come with all the necessary nuts and bolts to secure it to the chassis.
  • Temporary removal of the rear bumper is the prerequisite for the (de)installation of the tow bar both on a Jimny 3 and on a Jimny 4.
    • For Jimny 3, you will need to remove the rear (vertical) lamps as well before removing the rear bumper.
  • If you want to increase your chances of ever dismounting the tow bar in the future again, it might not be a bad idea to spray / coat the nuts and bolts with some anti seize chemical before mounting.
  • If your tow bar came without the instructions on how much to torque the bolts, this web article might be useful.


If your tow bar came without the mounting hardware, you will need:

  • Four 12 mm x 35 mm hex bolts and one 10 mm x 35 mm hex bolt;
    • All bolts should belong to the strength class 8.8 or higher.
    • Bolt length of 40 mm is also OK, but leaves more of the tread protruding up which corrodes and becomes harder to unbolt later on.
  • Four 12 mm nuts and one 10 mm nut;
  • Ten large washers;


Wiring the tow bar electrics

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If you do not intend to tow a trailer, or are not required to have additional brake+turn lights on the tow bar mounted cargo boxes or bicycle carriers, then you do not need to install wiring for the tow bar electrical socket.


Suzuki did not install wiring for the tow bar in Jimnys 3 which did not have factory-fitted tow bars. Situation with wiring in "towbarless" Jimnys 4 is currently unknown.

Tow bar electrics need to be wired in parallel to the existing factory wiring harnesses for the lower rear left (bumper) lamp and for the upper rear left (vertical) lamp.


If you have to install wiring for the tow bar, there are two solutions available:

  1. Solution A: Using official OEM tow bar wiring kit;
  2. Solution B: Using any tow bar wiring (for any vehicle or from any vehicle from a vehicle junkyard);


Preparations

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Whichever solution below for the wiring that you choose, the preparation (to access the existing wiring in the vehicle) is the same:

  1. The rear bumper should have already been removed as you are installing a tow bar;
  2. Remove the rear left seat;
  3. Remove the plastic trim from the bottom of the rear door opening;
  4. Remove the large lower rear left plastic trim (between the rear left window and rear left wheel arch);
  5. Optionally: Remove the rear left seat belt winder;

The preparation procedure for Jimny 4 should be similar.


Recommended additional works

While the rear part of vehicle's cabin interior is dismantled and removed in order to install tow bar wiring, you might use the opportunity to perform some additional works in the exposed cabin sections along the way.


Solution A for Jimny 3

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You can buy an OEM tow bar wiring kit from Suzuki. The kit contains the wire harness with proper connectors, as well as the large external connector for the towed attachment (either 7-pin or 13-pin, depending on which kit you buy).

  • The wire harness from the tow bar wiring kit plugs neatly into the existing wiring looms for the the lower rear left (bumper) lamp and for the upper rear left (vertical) lamp.
  • Those two factory looms in the vehicle for the rear lamps are not continuous all the way up to the lamps.
    • They are "interrupted" by a pair of male+female connectors just before they exit the vehicle near its rear end.
  • When installing the OEM tow bar wiring harness in the vehicle, those factory looms to the rear lamps need to be disconnected at those points.
  • Then the tow bar wiring should be connected there.
  • Since the tow bar wiring harness has special "split" connectors, it is possible to connect back the remaining end sections of the factory looms towards the lamps into a "Y" (parallel) wiring configuration with the tow bar electrics.


Note Icon.pngThe wiki article "Accessories for Jimny (genuine Suzuki)" contains info on OEM tow bars and related accessories (like wiring kits etc.) (look under the section "Tow bars")


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Solution B for Jimny 3

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Introduction

If you do not use the OEM (or equivalent) tow bar wiring kit, then you will have to splice several wires in the rear section of the vehicle and either solder the tow bar wires to them, or use "scotch locks" to clamp the tow bar wires to them.

Note Icon.pngYou will void any vehicle's warranty if you alter the wiring in the vehicle in any non-official way.


Warning Icon.pngImproperly fiddling with electrics can produce a significant safety (fire) risk in the future. Therefore, this job is best left to be done by reputable vehicle electricians.


However, if you are confident to do it yourself, or if you want to get yourself acquainted before visiting an electrician, read more about the solution below.


Procedure

The 7-pin electrical socket on the tow bar should have a cable attached with the following wiring:

Figure 01 - tow bar socket wiring pinout on Jimny 3



Terminal number Function 7-core wire colour
1 Indicator left Yellow
2 Rear fog lamp Blue
3 Earth White
4 Indicator right Green
5 Side lamp right (also marker lamps & number plate lamp) Brown
6 Brake lamps Red
7 Side lamp left (also marker lamps & number plate lamp) Black


The cable from the tow bar needs to be connected into the Jimny 3 wiring harness that powers the lower rear left (bumper) lamp and the upper rear left (vertical) lamp.


Access procedure:

  1. Remove the rear left seat;
  2. Remove the lower rear left plastic trim (between the rear left window and rear left wheel arch);
  3. This will reveal the wiring harnesses that go to the rear lamps;


The Jimny 3 wiring colors at the rear lamps is as follows:

Jimny wiring
color
Jimny function Tow bar wiring color
red / green indicator left yellow
yellow / green indicator right green
green / white brake lamp red
red side lamps brown / black


One of the pictures below shows the wire splicing method by using "scotch locks".

Note Icon.pngUsing "scotch locks" (or any other non-soldered wire connection) is generally considered an unsafe / "el-cheapo" connection method, which has a long term risk of producing electrical glitches or even catching fire!




Using bicycle carriers or cargo boxes

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Bicycle carriers

The wiki article "Bicycle carriers" contains everything about choosing and using bicycle carriers on a Jimny, including tow bar mounted ones.


Cargo boxes

The wiki article "Cargo space expansion and management" contains a dedicated chapter about tow bar mounted cargo boxes and dog boxes.


Common remarks

Beware that the load limit for most tow bars is in the range of 50 - 75 kg! (Nose weight - the vertical weight on the ball/hitch). You must count in the weight of a bicycle carrier or cargo box together with the bicycles or cargo when doing the weight calculation.


Note: Using tow bar mounted bicycle carriers or cargo boxes can have legal restrictions in some countries. Examples could be mandatory additional license plates and brake + turn lights on those objects, or issues of animal treatment if transporting hunting dogs, etc. These all are non-Jimny related generic issues which you need to explore on your own.



Page last edited on 4/10/2021 by user Bosanek