Front strut remove & install

[3C4M Guy]

I'm in the middle of upgrading the front struts (and springs) on my B6 Passat. Despite using a spreader tool in the split of the hub/wheel bearing housing, I've found it quite difficult to remove the strut due a tight fit. When installing the new Koni struts, it's proving to be even more challenging to insert the strut to the full depth inside the hub. What I thought would be a simple job is taking forever!

Has anyone stuck a similar problem? Any tips?

There are two main methods to install: (1) attach the top of the strut to the turret, then engage the bottom of the strut with the hub and lift up the hub, with a trolley jack if necessary, so that the strut fully enters the hub or (2) insert the bottom of the strut into the hub first and bolt in, then lift the complete unit up into the turret and attach the top of the strut. Any tips on which method works best?

Thanks.

[Martin]

I know exactly what you're going through - having done it to a Skoda Octavia and Mazda 3

A nylon hammer to belt the cast iron hub helps for the removal

Use method 1 but clean the hole in the hub where the shock goes into and then spray WD40 in there
When you apply pressure from jack do it gradually, rock the shock to help it align with the hole in the hub,
at some stage it will pop in and from there it's easy to jack until full engagement has been achieved

(I very much doubt that method 2 would even be possible)

[3C4M Guy]

I appreciate your reply Martin. I've previously changed springs & shocks on other cars including a Lancer and Commodore and it was a breeze compared with a B6 Passat. Even a B5 Passat looks easy.

Method 1 is recommended by the Haynes manual I have. I'll try some further cleaning of the hole + WD40. The hub is actually aluminium so I've been hitting it with a mash hammer via a piece of soft timber. I've found that using a slight twisting motion as well as rocking helps. The strut is now inserted about 60mm out of the required 75mm but won't go any further. I've tried jacking under the disc as well as under the control arm. Now that the strut is partially inserted I may be able to swing the control arm away and jack under the hub to avoid any alignment issues. Other than that I'm running out of ideas.

Believe it or not, method 2, which is inserting the strut into the hub first then raising the whole into the turret, is actually recommended by the VW Technical Centre who publish the workshop manuals used at dealerships. Someone is Russia has published them on the internet. If anyone is interested, I'll give you the link. There's even a special VW tool - a step ladder VAS 5085 to climb in order to fix the top of the strut with the 3 bolts!!!

If I don't have any success with the cleaning + WD40, I might have to fall back on a 3rd method which would be remove the brake calliper and disc plus the tie rod, then insert the strut into the hub on the bench. A lot of extra work.

[Martin]

Yeah - every car is a little different

Have you tried putting a pry bar (or sacrificial screw driver) into the hub gap and levering it open a little while the jack is applying some pressure from below?

Sounds like you're close - some lube and much cursing may get you over the line

[3C4M Guy]

I'm using the correct strut splitter tool 3424 similar to the one pictured. I've moved it down below the level of the bolt hole on the flange so that it doesn't interfere with the side plate on the strut. The tip of the spreader tool being hardened steel puts a fair dint in the flange of the alloy hub. Yes, maybe more grease and cursing.

[Martin]

Another tip (I had to do this to the Mazda) - put the spring compressors on to the shock springs while still in the car - compress the spring - this will help reduce the downward force and downward shock travel

[Umai Naa!!]

It's quicker to strip the whole lot down to just the strut and knuckle, than it is to struggle with it all still attached to the car.

Also measure the diamter of old Vs new struts. They can be different.

[3C4M Guy]

Did it! Thanks all.
I finally spotted that the new strut had a very minor manufacturing defect. A small ball of metal from welding splatter had attached itself to the lower part of the strut, had then been painted over and was preventing it from inserting fully. Once I filed it off, cleaned the hub bore with WD-40 and applied some grease, it slid straight in with no effort.

I've been writing up my own workshop manual for this exercise using VWTC diagrams. So if I ever have to do it again ...