Good stuff wrt your son's A4 etc. I used Autohaus twice recently as you had said earlier in the year that your son had used them and it had turned out okay. First visit for my 2011 Audi S4 for a 4 wheel alignment check after I had eventually replaced too much of the front suspension - the alignment error after doing all that work was negligible and really the steering tracking had to get moved over slightly. The second time was to get the cam belt replaced on my wife's 2015 VW Polo 1.2TSI 110PS 6MT - really as it was just over 10 years old and just over 50,000miles, if it was ever to get that belt replaced while in our ownership, it might as well be now! My own slight moan there was that they sprayed some funky plastic panel cleaner on the engine plastic parts - and that stuff smells as sweet as my dearly departed MIL's "going out" perfume, when I got out of it after driving home, I got a shock by smelling that smell!
Anyway, a couple of spanner swinging tales, the 2011 Audi S4, yes these top bolts do really get stuck in the top of the aluminium uprights/hub carriers, also the similar lower pinch bolts are more of the same. Most people don't need to remove the lower pinch bolts as the lower ball joints can last for ever, but I had set in my mind to replace the lower ball joints as well as all the other arms top and bottom, mainly as just after my car was built, Audi increased the size of these lower ball joints - and only the lower pinch bolt on the RHS upright eventually came out intact, sadly the one on the LHS snapped off, I tried too quickly to drill the remains out while the upright was still fitted to the car, and ended up drilling into the thread at one point, so an easi-out could not be used, so I dug deep and ordered in a pair of new Audi uprights as I had also failed to make much progress on removing the long top pinch bolts. Tools used were arm hammer, mapp gas torch, lots of release oil, lots of time between attempts, Blu Tac to build up "bunds" to hold/
store the release oils in, and finally a induction heater. The way I see it, as well as steel passing through aluminium issue in an area where salt is used on roads in winter, there is the fact that Audi used low strength bolts for all these pinch bolts as they don't get tightened up much - so you can't apply much force to try to break them free, I knew this and initially thought that I had freed up the second side, ie the LHS lower bolt, but it soon became obvious that while I could get the bolt to start moving slightly and then gradually a bit more - only one end of it was rotating - game over! Anyway, if I ever did that job again, I'd just remove the lower arms inner bolts and the top arms inner bolts, damper leg lower bolt and drive shaft bolt - and lift the complete assembly off the car - after removing the brakes etc. As it turned out the brakes had a "bit of a feel" to them around this time, one wheel bearing was rusting and so "eating" the ABS wheel sensors and the splash guards were rotting at 2 of the 4 fixing points, so a lot of what I had to remove was replaced with new parts! That stole too much time over the summer period!
Next the 2015 VW Polo 1.2TSI 110PS, as it was filled with G13 coolant at the factory, at 10 years as that car does not have a silicate pouch to "boost" the G13, the ph value is heading towards being acidic. So, a few weeks ago, just before it got colder, I popped along to Bilston business park to buy some extra G12evo so that I had enough G12evo to change the coolant in that Polo - the VW Van Centre had closed and moved away, now over at Newbridge and run by Western - so sod that, bought a couple of bottles of VW Group G12evo online to avoid driving across/along the city bypass - a bad move as the sellers package was deposited in their local EVRI locker, was collected by EVRI and never made it into the system, so after maybe 10 days that order was refunded and I bought online again, that order dragged its heels, again with EVRI by accidentally with a different by with a similar name, seller. Then we were down in Bromley visiting our younger daughter and her family, so yesterday was finally "coolant changing day" as it was a warmish day. Well I couldn't get the hose clip off the main engine coolant hose using my angled hose spring clamp pliers! Now I have worked out that VW Group, when that car was built, used "pre locked open" hose spring clamps and that means when you use normal spring clamps on them you can only open them "almost" enough before one part fouls on the lug/latch that that type have to lock them open for initial use!. The replacement spring clamps don't have this feature so they are just the usual type that get stored closed and you only open them with pliers when you start to fit/use them. I didn't expect to find that so I'm waiting until the new hose spring clip turns up before restarting that job. Blinking progress, sometimes it can be hard. The smaller charge cooler pipes have normal hose spring clamps so I don't think that they will cause any issues.
All I need now is another warmish day - or I'll splash the cash and heat the garage and car up before starting that job, I can confirm that VW Group G13 is extremely sweet to the taste though - but I probably knew that it would be before getting some dripped onto my face.
Edit:- finally got access to older daughter's 2019 SEAT Leon Cupra to change its engine oil and filter - a bit late in the year to need to work in the garage! Still got the job of removing the front diff lock (VAQ) Haldex fluid AND remove and clean up the pump and the area it is located into, maybe that will wait until the spring time. Again I chose to buy the Haldex fluid online, first bottle sent out was the wrong version, it seems that it is what is used on Skoda and VW Gen 5 Haldex units but not in same age Audi and SEAT Gen 5 Haldex units - different health warnings on both bottles, one fluid made in Sweden which is where Borgwarner are based, the wrong one was made in Germany so maybe some of these parts/units are built under license out of Sweden and some materials are different. A strange fact, lots of the motor trade supporting VW Group products consider that Febi is quality stuff and can be trusted, the Febi offering for both these versions of Gen 5 Haldex fluid is the same.