How-to: B7 Avant auto boot opening

JMGR33N

Registered User
Hey all, I've been looking at knocking up something to do auto boot opening on my Avant for a little while. Finally got it to work how I want.

So here's what I did...

Firstly ordered a pair of new gas struts. I got the 2005 A6 Avant ones. They are the same length as the B7 ones I had but higher pressure. (£13 eBay)
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Old
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New
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I also ordered a pair of engineering compression springs, 38mm long x 16mm diameter. (£2 eBay) **See Note at bottom**
And
Pack of 4 washers 8.5mm internal diameter x 16mm external diameter. (£1 eBay)
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I also bought 30cm of black shrink wrap. (£1 eBay)

Next unscrew the ends off of the new struts
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Slide on one washer
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Slide on one spring
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Slide on the second washer
1e1e254c90edcf1a2a062d3d7ccd3276.jpg


Screw the end back on the strut
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Cut a piece of shrink wrap long enough to cover the spring and washers with a few mm excess at either end.
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Hold the wrap in place and shrink it down with heat. I used a mini blow torch.
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Do the same to both new struts and then replace the old ones on your car with these.
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**NOTE: after first fit I found the springs were too long so I measured up and found that they only needed to be approx 18mm long. So I cut one spring in half and ground the cut end flat**

Here's the finished article:
 

SDHA4SLine

Registered User
Brilliant, great mod well done sir. I shall be copying you very soon :).

Now if you could just figure out mod to auto close ...;)
 

alpesh26

Registered User
Nice work!! Would this work on a saloon?
 

JMGR33N

Registered User
Nice work!! Would this work on a saloon?
No idea mate, deff not with these particular parts.

I believe there are proper sprung oem hinges you can use on the saloon. Think there was another thread on here talking about.
 

sabaxter

Registered User
Brilliant write up and video
 

gary_a4_quattro

Registered User
Great modification , clear and concise details too ! Top job ! :icon thumright:
 

JMGR33N

Registered User
In all honesty I couldn't say for sure. In principle it should work. But I don't know if the B6 struts are the same length, what pressure they are and what size spring would be needed.
You need to do some carful trial and error.
 

JMGR33N

Registered User
No not daft at all.

the answer is yes, it did make it fractionally harder to pull the lid down. due to the extra pressure in the struts, but the springs only compress on the last few inches of closure so have the whole lids weight in them. so have not found it any different getting it to latch shut.
 

DrEvil

Registered User
Cheers for the answer.

I was just wondering if I was to do this, if the missus would end up moaning at me because she would have trouble closing the boot!

Another question, if you open it by hand, is quite a forceable open (it looks fairly controled from the video)

Good cheap mod, and easily reversible so am tempted to look into it!
 

JMGR33N

Registered User
Opening by hand there s not a lot of difference, there is not a lot of force in the initial pop.

To be honest you could probably use struts with less pressure than i have. I just didn't want to spend a fortune buying all different pressure struts to test them so i went pretty high. 105nm more than standard.

It's not an oem mod so i know its not as refined as Audi could have done it, but like you say if you don't like it, for the sake of 20 odd quid its not the end of the world.

I bought a classic bug so i wouldn't fiddle with the Audi, that hasn't quite worked out... lol
 

JMGR33N

Registered User
If you want to give me a saloon to keep then yea! ;-)

There's an OEM way of doing this on the saloon with proper sprung hinges. I'd go that route if i had a saloon.
 

Broken Byzan

Photographic Moderator
Staff member
Moderator
VCDS Map User
I don't suppose you have the dimension of the struts to hand.? Means I don't have to buy many different ones to check spec . Unless etka has the ratings and lengths. . Hmm
 

B_FUR

Registered User
top job mate and great write up. I think even I could manage to do this one!!
 

markspark

Registered User
The only problem I can see is if your sat at home with the key in your pocket with the car parked close by and you catch the button the boot would open without your knowledge
 

JMGR33N

Registered User
It's a possibility but no different to winding down all your windows by accident, by sitting on the unlock button.

You have to hold the button solidly for a good 2-3 seconds so I'd say it'd be unlikely.

But technically yes you are correct.
 

Weverall

Registered User
Just waiting on someon to do this for the cabriolet..

any ideas on strut length or how to find a higher rated strut the size of a cabriolet one
 

JMGR33N

Registered User
One thing I should have mentioned. It is difficault to determine exactly what length you need to cut/buy the springs all cars a very slightly different. So what I found works really well is buy 4 extra washers. And you can use them as spacers, to fine tune the amount of "pop" you get.
 

barkclark

Registered User
I am so doing this to my B6! I see you bought struts with a higher pressure. Any idea if it would work with lower pressured standard B6 / B7 struts?
 

barkclark

Registered User
Also have you got a part no. for the struts you used?
 

quiksilver_jake

Registered User
Same as Barkclark^ but debating doing it with standard pressure ones as it goes up with what looks like alot of force!
I had the same concerns about closing as people have had further up the thread.
 

barkclark

Registered User
I think I'm probably just going to give it a go with new standard struts!
 

quiksilver_jake

Registered User
I thought I best check mine boot unlock button works first as I've never used it, Looks like its sending a signal but not unlocking so looks like I'll have to fix that before I can carry out the MOD. :(
 

DerClown

Registered User
Just waiting on someon to do this for the cabriolet..

any ideas on strut length or how to find a higher rated strut the size of a cabriolet one
Looking forward to do that !
Give you info If I be victorious :)
On my wifes Avant I do this mod for sure !
 

novril

Registered User
Any chance you could link to the struts you used with removable ends? The ones I have tried dont have threaded ends!

Eager to give this a go now.

Cheers, Mark.
 

I'm Just Rob.

Moderating or something,
Staff member
Moderator
VCDS Map User
Gold Supporter
a great mod and i'm looking to do it myself ,but, i do have one concern to be honest that i would need to check before doing it to my avant.
Having watched the clip a fair few times i would be a little concerned on how the effect of continued shaking/clonking of the gas strut mounts when the tailgate opens and then stop abruptly at the fully open position.
under normal usage the opening of the tailgate is not subject to quite such a sudden jolt as it is under a more controlled force, the human arm/hand as it after the mod and i can see possibly problems arising around the gas strut mounts and the tailgate bracket that the strut attaches too becoming loose etc or the joints becoming problematic.
Maybe some sort of rubber buffer/damper on the strut to deflect that inital shock maybe a good addition, on motorised tailgates the rate of opening etc is controlled by a motor.
just a thought chaps to enhance a great idea and mod, and possibley save a bit of wear and tear.
 

SootySport

Registered User
Great idea this but stand back from tailgate, wouldn't want the tailgate catching you on the chin.
 
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