.

 

Thanks.
Subscribed.


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Hi Sumotoy


I have taken what you have said onboard. I have a 2017 v8 TDI and have contacted 4 4wd places here in Australia to have a front recovery point fitted. I have been met with blank stares and told there are no products available. An example of a response is this..


"
We have done a bit of research due to the lack of pre fab points. Unfortunately we wouldn't be able to help as there hasn't been an area on the chassis to mount them due to lack of strength to meet Australian standards. Public liability would become a big issue. ARB also won't be making them due to this issue.


Sorry we can't be of assistance on this but we can't risk any product failure."


Do you, or does anyone here, have an idea as to how to fit rated recovery points to this vehicle? Pics would be great!


Cheers
Brian

 

A lot of liability in all that nowadays, with airbags and crash zones etc, and it doesn't help it is not a frame chassis. I don't use my treg for more than light offroad, so the only thing I could think of is mounting a frame that uses the subframe bolts in front, and has the recovery gear attached to that.

In lieu of that, the only real answer is to always use the rear tow receiver. That may not always be practical, but I just don't see any other way. I'm also not convinced the safety standard I listed means that two eyelets with a harness, means you double the pulling capacity. You are only spreading the load, but the limit doesn't really change with that standard.

If you do figure it out, please post. A lot of lucky Treg owners out there using those front eyelets when they really shouldn't be.

Cheers

Scott J
'07 v10tdi - Xena
'03 Suburban 2500 - Thor
'94 FZJ80 Landcruiser - Sumo

 

Subbed!

Great topic. I interpret the literature the same overall as you Scott.

My only conflict may be with using the dual hooks in the front to spread the load to ~7000lbs (3500 per eyelet). It would be reasonable to assume the two hook/eyelet would be feasible in the rear up to the towing rating of 7716lbs AND which equals what you could snatch with a tow hitch mounted for recovery per VW. So really the question is the capacity of the Front bumper assembly in relation to the rear for a snatch rating. Which translates to IDK for the Front...

 

I am not sure I agree that the rating doubles with 2 eyelets. If it is a straight line pull vertically and horizontally, the stress of the EU test pull would be on the bumper, which is mounted in 2 spots, so the load is already spread to the other mounting point. Rephrased, the EU single pull test is not isolated from the other vehicle mounting point. Secondly, a bar to maintain the straight line load on the eyelets would be required to even make this argument. Equalizing the force isn't going to help if the result is taking the recovery forces on the eyelets off vertical/horizontal planes.

I'm sticking to a rating of 3500lbs, possibly increased with the use of a equalizer bar that maintains the pulling forces in the same vertical/horizontal plane as described in the EU test.

Not being a downer, just thinking there are a lot of lucky folks out there!

Cheers

SJ

 

The Porsche Cayenne Transsyberia had a removable front winch. I assume that the design would be the same?

 

Or something like this:

 

Topline, I have been thinking a bit about adding some front hooks not because I need them but because I think it would be interesting (and I want to do some off roading). I have also considered a Winch mount.


What exactly are you looking for?


I don't see any reason mount points couldn't be added. I've been thinking about adding some over top of the stock threaded hole and using a dremel/hotknife to cut slots int he bumper to put them (similar to what Jeep owners have).


In all honesty I'm not sure why it couldn't be done. The question to me is one of distributing the load properly along the structure. Looking at the sub frame that I took off when I put my Hitch on they use about a 3/4" diameter weld nut to thread the recovery hooks into. The steel in the bumper bracket (on the rear) is maybe .040" thick but stamped.



As I mentioned I have been thinking about creating a front bumper reinforcement that would allow a winch and recovery hooks.


What sort of use would you put one under? What would you need it to do?

 

Hi NTDI


As the 4wd clubs here in Perth usually insist on 'rated recovery points' being fitted front and rear in order to join their club drives, I am exploring fitting a point to the front somewhere. I already have 2 VW screw in points and a bridle for the front. It would mainly be used for a snatch strap type recovery.



A 'plug and play' winch mount would also be very useful.



Cheers
Brian

Topline, I have been thinking a bit about adding some front hooks not because I need them but because I think it would be interesting (and I want to do some off roading). I have also considered a Winch mount.


What exactly are you looking for?


I don't see any reason mount points couldn't be added. I've been thinking about adding some over top of the stock threaded hole and using a dremel/hotknife to cut slots int he bumper to put them (similar to what Jeep owners have).


In all honesty I'm not sure why it couldn't be done. The question to me is one of distributing the load properly along the structure. Looking at the sub frame that I took off when I put my Hitch on they use about a 3/4" diameter weld nut to thread the recovery hooks into. The steel in the bumper bracket (on the rear) is maybe .040" thick but stamped.



As I mentioned I have been thinking about creating a front bumper reinforcement that would allow a winch and recovery hooks.


What sort of use would you put one under? What would you need it to do?

 

Topline, not too sure you understood what I was asking. How much load do the mounts need to handle?


Have you see these or these ?


I may build a set for my T3

 

Hi NTDI


I am not a technical bloke, not a mechanic or fabricator. I need to rely on the expertise of others. I guess the load would be 2 times the total weight of the vehicle. I am unsure of the force required to snatch a Touareg out of the sand on a soft beach. Most of the commercial recovery points are rated to 4500kg/10000 lb.



Thanks for the links!



Cheers
Brian

Topline, not too sure you understood what I was asking. How much load do the mounts need to handle?


Have you see these or these ?


I may build a set for my T3

 

I posed this question a little while ago too. I ended up buying a second towing eye for the front on my 23 V8tdi R-Line. I most certainly wouldn't be snatching with those though. It's a shame we haven't been able to come up with a solution. The only other thing I have been thinking about is a couple of these which turns the wheels into winches.
https://www.bogout.com/?utm_medium=serach&utm_source=adwords&utm_campaign=brand&utm_term=gift card&gclid=CjwKCAjw7MzkBRAGEiwAkOXexJdoTJUGmv6WNnArMP7U9Y--UlQaBf4lARz1H-K-8eOVeaAqlev10BoC0DMQAvD_BwE


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I guess my question is how much is a solution worth?


I only had one tow eye when I bought my Touareg used. I bought a second one because there was a slot for it. In the US tow hooks aren't required. However are a nice idea.


I could probably fabricate a plate to give better tow hook points. and possibly a winch. No reason not to mount some clevise hook points. It would take a little engineering but it could most likely be done. I'd just have to take my front bumper off and get started....

 

make me one too!
$!

 

Interesting topic. The old school way is to definitely have big chunky red coloured rated recovery points, not only to ensure maximum safety but appease the old school types and some clubs.
Another distinguished, conspicuous sign of hard core offroader vs a softie perhaps ?
Reminds me of the live axle debate.

Jokes aside, I have been using the eyelets individually and with bridle at times over the last 15yrs with no problems.
I have never heard or seen an eylet recovery point fail so far.
I recall trawling through engineering sites to check strength and durability of welded vs screw/bolted applications to learn about atomic fusion of materials and load spreading through bolt threads.
At the end I am comfortable with the eyelets.
A deep bog in sand can put immense load on recovery gear when snatching, but then you make it easy by digging out as much and throwing your max trax under.
But please if anyone has any video or data on any eyelet failing during recovery in the last 20-30 or 50 plus years then please share.

 

Topline that is my logic as well. I am using a bridle and two two points with a rated snatch strap. I am also using two soft shackles. Nylon ++ load rating through the eyelets plus a bag over the snatch strap to stop whiplash.

I understand there a limits to my understanding of load but that is the best I can do at present. There is no other information and what was given in the original thread starter suggests I am ok. Two tow points is 3200 kgs. I am willing to be corrected!

 

Interesting discussion... I'll add in my 2c

I'll just premise this post with a very short background in that I have designed a few hoists and other lifting equipment in my line of work.
I will provide a few observations around loads and safety factors of lifting/rigging equipment.


In general if an item normally used for lifting is then used in a horizontal application (hoist vs winch - disregarding other safety features required) or non-lifting application (lifting vs lashing) the safety factor is halved (capacity doubled)

The Touareg Expedition winch had a capacity of 9500 lbs (4300kg)
Hoist ropes typically have a 4:1 safety factor (in a winch application that would be reduced to 2:1) so the mounting of the winch should be capable of supporting a minimum 8600kg.
The Expedition winch is mounted to the car via the same 8x bolts as the bumper reinforcing.
The four Grade8.8 M10 mounting bolts on the winch have a shearing load of approx 2650kg each through the thread. (Total 10,600kg)

I think it would be fair to assume that the chassis would be good for at least 8500kg.


The VW tow eye is an M18 left hand thread.
An M16 high grade bolted lifting eye has a straight pull working load of 4t with a 4:1 safety factor.
So the thread in the bumper reinforcing should be up to the task.

 

Agree, thanks!

 

Except the bending moment of office tee loads needs to be considered. On a bolted connection like the Euler requires a sufficient tension to load the washer area with enough compressive load to cover the bending moment at the interface point.

Thus the off axis loading is a concern.

The real issue is the design of the bumper bracket and it’s attach point in off axis loadings.

 

Definitely side loads need to be considered. I'll bet there's notes in every ARB recovery point packaging that mention side loading considerations.

The bolted lift point I mentioned above drops to 1.5t lifting WLL at right angles. Still 3t capacity in pulling application. (6t break load)

 

The bolted lift point I mentioned above drops to 1.5t lifting WLL at right angles. Still 3t capacity in pulling application. (6t break load)

Forgive me if I ask a bumb question, how does M16 high grade bolted lifting eye you mentioned compare to the the VW supplied M18 eye, can we draw any engineering comparisons between the two from a recovery viewpoint?


thanks,


TonyB

 

Thanks for the explanation, that RUD VRS starpoint certainly looks waaaay beefier than the VW tow eye, next question do they make it in left hand thread so that it could be used instead of the VW one in recovery applications?


TonyB

 

I'm a little confused now if I'm honest. So what you are saying now is to not use a bridle between two eye bolts on the front?

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Not exactly, but must be used with caution.

Using M16 as the example;
If you use a single eye and pull it from the side, you have a capacity of 1.5t.
If you use two eyes and a 60 degree bridle, you have a capacity of 2.6t
If you use a single eye and pull it straight only (give or take a few degrees) you have a capacity of 4t.
If you use two eyes and a spreader bar in a straight pull, you have a capacity of 8t.


I know this as I use it regularly, but you never know how many others know it, so I'll add it here also.
To make a 60 degree bridle, the two chains (or soft slings) need to be the same length as the distance between the two eyes.

 

So, is it better to use one strap on one eyelet, and another strap on another eyelet to make the length coming away from the car (ie. straight in front of the car) longer? Say, trying to use two 5m straps, one to each eyelet? I haven't bought any straps yet. I only have the second eyelet. I'm trying to decide what to do. Cheers.

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What size is the eyelet bolts on the Touaregs anyway? Any ideas?

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Yes the increased length does reduce the side load applied to the eyes.

From what I've found the factory eyes are left hand M18 thread.

 

Indeed the factory eyes are LHT-M18

To the eyelet Weight rating. The factory eyelet in my rig does not have any direct crossreference load stamping. However, I did order 2 additional replacement eyelets. (www.towhooks.eu PN: BK 013) They appear much beefier than the stock one in my truck. They are stamped ISO5422. ISO 5422 puts the rating of the BK013 at 3.5tons = 7000lb. I will use these as my calculations of load to PJMax 'equivalent'

Using the lift guidelines PJMax presented, here's my calcs

On-center measurement between eyelets in the front of my 07 touareg:
FRONT on-center measure = 100cm = 39.5in
60 degree dual eyelet - distance from bumper to single pull point = 35in
Pull rating at 60 degree dual eyelet harness pull to single pull point (3.5T * 35% correction factor) = 2.275T = 4550lbs or 2064kg

20ft strap used for dual eyelet distance from bumper to single pull point = 118.5in
20ft strap pull rating dual eyelet harness pull to single pull point (3.5T * 11% correction factor) = 3.1T = 6200lb or 2800kg


REAR on center measure = 115cm = 45.25in
60 degree dual load harness distance from bumper to single pull point = 39in
Pull rating at 60 degree dual load harness pull = 2.275T = 4550 or 2070kg

20ft strap used for dual eyelet distance from bumper to single pull point = 117.8in
20ft strap pull rating dual eyelet harness pull to single pull point (3.5T * 13% correction factor) = 3.05T = 6100 or 2760kg

What all this means? A dual pull harness without a spanner bar does not double the capacity of the single line pull. IF you could put a spanner bar that is exactly equalizing the forces on the 2 eyelets (in the horizontal and vertical planes), you 'might' equal the GVWR of the Treg in a pull. The problem is, you will never exceed the GVWR using the eyelets in tandem, ever. Which means buried in mud or sand or other mire that causes a multiplication factor to be applied to the GVWR for recovery, using dual eyelets still comes up short.

Cheers and hope this helps

justi
07 v10tdi - Xena
02 Suburban 2500 - Thor
94 Landcruiser - Sumo

 

Ok, here's some actual data for those of you who may be interested. I apologize for no pictures, can't seem to upload them right now.....
The following are the results of my personal research and investigation into the structural strength of using the "tow eyes" fitted to the VW Touaregs, both the 7P version (VW stated GVWR of 6305 lb) and the previous 7L version (VW stated GVWR of 6493 lb). (This also may apply to the Porsche Cayenne, as there is much component sharing between the vehicles.)
(All figures given in pounds force (lbf) and refer to relevant engineering standards describing minimum ultimate tensile strength (breaking strength))
-The detachable tow eyes have four threaded receptacles permanently mounted on each vehicle; two on the front bumper impact beam, and two on the rear bumper impact beam. The bumper impact beams are bolted to reinforced welded end-plates of the front and rear vehicle sub-frames longitudinal members.
( Note that in this application, all fasteners are subject to tensile force loading, and not shear force loading, which, although values are not normally provided, is considered to be only 60% of the fasteners rated ultimate tensile strength. )

----------
Detachable tow eye information:

-VW Touareg T3+ (7P series) part number 7P0805783
(M18-2.5 left hand) Forged pad eye (31mm dia.) flanged and machined base, slightly longer than 7L eye but with heavier stock (24mm dia.) to compensate, 18mm neck at the eye. Two tow eye of this style were tested.
-VW Touareg T1, T2 (7L series) part number 7L0805783A
(M18-2.5 left hand) Forged pad eye (31mm dia.) flanged and machined base, 18mm neck. Two tow eyes of this style were tested.

-Porsche Cayenne part number 95572115100 (however, it does appear identical to VW 7L units) was not tested.
-Audi Q7 part number 1T0805615A (longer bodied tow eye, no flanged base, seems to be used on most Audi and VW cars) was not tested.


Tow eye attachment thread strength:

(Steel grade is unknown, however, consider the fact that all other tensile fasteners used for Touareg bumper element attachment are grade 10.9)
For an M18-2.5 thread (minimum ultimate tensile load)
Grade 10.9 steel (possible) -44,962 lbf
Grade 12.9 steel (likely). - 52,605 lbf

Oval eye section strength:

Forging of eye side legs taper down to the eye tip semicircle, cross sectional diameter at tip is approx. 12.5 mm.
(Typical Breaking strength rating for a forged steel ring of that size is 11,450 lbf)

Tow eye testing:

All four tow eyes were tensile tested to destruction by a professional rigging company, on their large hydraulic rigging test bed. The results of each test were monitored by computer and a test result sheet and graph were produced for each. All four tow eyes failed in a virtually identical manner. After some elongation of the eye portion only, they fractured at the transition of the eye tip semicircle to either eye leg, completely separating the load bearing semicircle portion in each case.
7P type- Two new, unused eyes of this type were pulled to maximum load destruction, sample one failed at 39,300 lbf, sample two failed at 41,200 lbf.
7L type- Two new, unused eyes of this type were pulled to maximum load destruction, sample A failed at 39,100 lbf, sample B at 39,300 lbf.
In no case was there evidence of either attachment thread, flange, body or neck distortion, when inspected after destruction.

Due to the very close range of failure load values in the four samples, we can reasonably assume for our purposes that the OEM VW Touareg tow eyes are of very high quality and consistent strength, with an individual component minimum ultimate tensile (breaking) strength of 39,100 lbf.

Vehicle structure information:

Front Touareg bumper (impact bar crossmember) as fitted originally by VW, is attached to engine main subframe by eight M10 grade 10.9 bolts, four on each side (surrounding the tow hook attachment points).
Minimum Bolt strength, each - 13,556 lbf
Per side (4 bolts) -54,224 lbf
Total (8 bolts). - 108,448 lbf


Rear bumper (impact bar crossmember) as fitted originally by VW, is attached to rear main subframe by eight M12 grade 10.9 bolts, four on each side (surrounding the tow hook attachment points).
Minimum Bolt strength; Each - 19,716 lbf
Per side (4 bolts) -78,864 lbf
Total (8 bolts) - 157,728 lbf

(Front and rear bumper impact bar crossmembers are of varying designs, but are observed to be highly engineered items, comprised of both pressed and flat steel elements formed and welded together, with the full thread depth tow eye receptacles of machined steel stock, both flanged (against pull through) and fully welded into the built up structure, at the tip of a tapered steel cylinder, with its base surrounded by the four (per side) side frame attachment bolts. Both in compression, and tension, these structures appear extremely robust and capable of complementing the strength of the related fasteners.)
----------------------

My Conclusion:
To me, this information does indicate, that on a VW Touareg of any series, the factory towing eyes, and related factory original substructure, are designed and constructed to be of more than sufficient strength in order to allow safe recovery of the vehicle using either single or dual tow eyes at either front or rear locations. (It makes good sense to have the weakest link being the tip of the eyebolt, so as to mitigate structural damage to the vehicle in case of overload.) As to why VW does not indicate this ability specifically, or have a load rating indication on the tow eyes, is most probably due to liability concerns.

Notes, and things to bear in mind;
-Tow eyes must be installed as per the VW operators manual, ie, fully threaded in to seat the flange, and properly tightened.
-If a bridle is used, the tow eyes should be secured in the correct orientation for side loading (this can be done by inserting a shim washer, of no more than one thread pitch thickness).
-Please note that this information is only applicable to a factory equipped VW Touareg. If any of the substructure (bumper impact beams, aftermarket tow bars and/or fasteners) has been replaced or modified, weaker components may have been substituted. This especially holds true for the use of aftermarket tow hitches, aftermarket fasteners and aftermarket tow eyes.
-Retail vehicle recovery gear (tow straps, dynamic recovery straps, winch lines, etc) has no mandated safety factor, and as such, strengths specified are often average (not minimum) breaking strengths (regardless, most professional tow and recovery operations try to maintain a minimum 2:1 safety factor). This is not to be confused with professional rigging gear (for overhead lifting) which is normally rated with a working load limit (WLL), being the minimum ultimate tensile strength (breaking strength) divided by 5, to give a material strength safety factor of 5:1.
-Dynamic recovery, when properly done (ie, with a rated, rested line capable of proper stretch, and used as intended to free from a soft substrate such as sand, snow or mud, in a direct line and using the accepted one meter "S" of line slack) develops a surprisingly manageable force level. This article has the results of using a load cell to determine freeing forces,
https://www.outbacktravelaustralia....ustralia.com.au/driving-towing-recovery-techniques/snatch-strap-loading-on-test
-The ISO Standard, 5422 -1982, which has been referred to here recently, should be recognized for what it is, a MINIMUM performance standard of a vehicle component performance.

Cheers,
R

 

How good is this info, thanks!
Happy with the result.

 

Thanks Singh!
I'll try loading the photo again.
Pretty self explanatory, sample numbers are as in the report.
We never did find the missing piece of sample B, sorry....

 

Thanks for the testing results. These results would be significant to a straight line winch recovery, in vertical and horizontal planes per the owners manual. For real world testing to recovery in winch or strap, shear loads are the reality in 95% of all recoveries. The failures I observed firsthand of multiple eyelets were never failures of the loop. IME, the failures were shear force failures at a very low snap strap load, and they were at the neck of the tow eye. As I recall, in all instances threads stayed in the bumper, and the loop/eye was always intact, and still attached to the hardware on my strap.

When the bumper came through the cover (cayenne and panamera) the failure was observed corrosion on one bumper (colorado infamous mag cloride) and a bend to failure on bumper mount on the other.

Your results do indicate to me that if we assume a straight line vplane/hplane steady state (winch) recovery, the most likely weak link will be the hardware attached to the eyelet. Or in the case of the strap, the hardware attaching the strap to the eyelet.

Ideally, in a winch recovery in v/h plane would indicate your conclusions are true, all appears pretty beefy and overengineered. It's the other 95% of the time that is my primary concern. Drawing conclusions to that would require shear load testing at minimum.

Cheers and thanks for the data.

Scott J
07 v10tdi Xena
03 suburban 2500 Thor

 

VW engineers going above and beyond with their engineering once more. This sure is a valuable discovery and a huge peace of mind for us who like to leave the tarmac. Well done!

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