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I posted this over on CT, but thought I'd post here too.
I know a lot of people have been successfully using the VW Touareg tow eyes for vehicle revovery, but there hasn't been much in the way of supporting info out there, and a lot of negative speculation. Well here's what I found out, use it at your own discretion, and go out and play safe!

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. )

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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 massive hydraulic testing 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. (Sorry, but we never did find the detached portion of sample B, so it missing in the pic.)
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.

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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.)
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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.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 vehicle component performance.
 

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Chairman
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Good, thorough post. Thank you.
 
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