Having black cars/suvs/trucks most of my life; I have learned how to keep my ride mostly "swirl' free. It is not 100% perfect, however, it is pretty close. This pertains to RW as well as 2-bucket 2 gg. Since you use a foam gun that is a + especially in your weather conditions.
IMO it is your drying technique that needs improvement. I went through the same thing as you did with my black cars (RW or normal wash). The exception is that I never have and never will use a boar's hair brush or squeegee. I will not do a waterless wash as IMO it is not meant to be for a Black or Dark color cars...Again, that is IMO.
The 1st thing I see that can help you is DITCH the boar's hair brush. Get a step ladder and wash the Yukon roof with a MF mitt or equivalent (like the MFM Incredimitt). Even though the boar's hair brush is soft it does not matter on a black vehicle...it will scratch. Again, my opinion.
The 2nd and probably more important is DITCH the Cobra Waffle Weave Towels. Delegate them to clean the windows (and interior as I do). IMO, this is contributing to the scratches. I know from 1st hand experience. Don't get me wrong, they are excellent towels, however, not for drying a black vehicle.
3rd Get an electric leaf blower or (as I do) get a dedicated blower like the Metro Sidekick. The Sidekick has done wonders for helping me dry my ride. The electric leaf blower would probably be better for you as you have a large SUV.
4th Get some dedicated Micro Fiber (not waffle weave) drying towels. There are a couple of brands that are the best choice. #1 is the Microfiber Madness Dry Me Crazy Towels. These IMO are the best for drying....period. Use them in conjunction with the blower (leaf or Metro Vacs or Sidekick). Another MF towel (I use in conjunction with the MFM towels and Sidekick) is the Dry-Me-a-River towels. Get their LARGEST size. It does not dry as well as the MFM's but they are large enough to get quite a bit of the water off and follow up with the MFM's if you can't use a blower.
The 5th and probably the MOST DIFFICULT IN LEARNING (for me at least) is to dry your car very gently. With the MFM towels it is possible. You do not need to grind or use a lot of pressure for drying your ride. A gentle touch is all you need. It did take me a while to "soften" my touch.
6th I LOVE Aquawax and have a gallon of that stuff with my sprayer. You can use Aquawax (or equivalent) as an aid to drying. You will encounter some dry spots (water) for taking your time to dry. Just spritz the dry spot and gently wipe with the MFM towel.
7th if you are going to follow-up with Aquawax once your ride is dry...dampen a quality MF Towel (Cobra Gold or equivalent) spritz and wipe and then follow up with a dry MF towel. Gently rubbing the area no more than a couple of times.
IMO this will reduce your chances of scratches. This is my technique and this is what I have done successfully. Some may disagree or think I am full of it. If so, so be it.
I would ask that you try this technique 1st and give me your feedback.
:buffing:
I respectfully disagree with some (a lot) of this. I'm a black car owner as well - and my car stays defect free. First, foam gun/cannon is fun - but does little to nothing to prevent swirls. IMHO, the key is taking your time to pressure wash the vehicle prior to touching it using a pressure washer (not a hose) to get the dirt off.
Wether or not you "foam" it first - doesn't really matter much IME. It should take 10-15 mins to pressure wash a vehicle like a Yukon sufficiently so the paint is safe to wash. You should slowly go over the paint with the pressure washer in a criss cross buffing like pattern for 3-4 passes or so. You should be concentrating more time on the lower / dirtier panels.
It seems a lot of people make the car wet, hose style, but don't spend the time to pressure wash the dirt off. Buying a pressure washer and doing that is the single biggest thing you can do to prevent scratches IMHO. If you don't believe me, find a dirty wheel and hose it off. Then pressure wash it - and see how much cleaner it is.
I don't see how drying technique matters at all. Assuming -
1. Your car has been washed properly
2. Your towels are clean and of good quality.
How does one scratch a perfectly clean car using towels that don't mar? If the car isn't perfectly clean - that's a washing issue; not a drying issue. If your towels suck - that's an equipment issue. A Metro helps, and I use the Sidekick much more than the Master Blaster, but - it's neither here nor there if the car is still dirty or the towels are dirty or crappy.
Onto the boar's hair brush. The BHB AG sells does not scratch paint if used as directed. In fact, it's gentler on paint than most wash mitts. How do I know this? Because I've tested it on my paint, I use it extensively, I reviewed it here (too lazy to link), and I've CD tested it. It just doesn't scratch. I'm sure you can find a way to make it scratch - but that is not using it as directed.
Waterless washes (the process - not the product) and in between wash "wipedowns" are likely the OPs issue IMHO. QD a dirty car is the fastest was to mar the paint. It's just a horrible idea. Waterless washes are better, but most people use far too little product to clean anything dirty safely IMHO.
Cobra waffle weave towels don't scratch black cars or any other cars if they are clean. Like a zillion and one AG'ers have been using these WW towels for years (including myself) without issue. The Cobra WWs are of high quality - I don't care if they come from Korea, China, or North Jersey. Microfiber Madness towels are of high quality (and you pay for it); but so are MicroFiber Tech's towels (cheap). You don't need a magic towel to dry your car. None of these towels will scratch it the technique is correct and they are clean and the car is clean. I've used/use all these towels + others without issue.
I agree AquaWax is great - but don't see how using it (or any other spray wax) would matter to prevent swirls if your drying a clean car using high quality towels. Aquawax is mostly water / alcohol / some surfactants & some polymers. The car is already wet (water); I just don't see how adding more water plus some trace ingredients make a difference on a clean car using clean towels of know quality and good technique. This is my experience as well.
I've dried my black car using spay waxes and not using spray waxes. Ive dried it using a Master Blaster or just using towels. Ive used DI water and I've used tap water. I've used quality towels from all sorts of vendors and countries of origin. I've used a boar's brush (Montana), a noodle mitt from AG, Griot's wash pad, BMWs sheep skin mitt, AG's old sheepskin wash pad, Dodo's Wookies Fist, fluffy MF towels, etc... to wash. I've used almost every brand of rinseless wash and almost every brand of conventional wash AG stocks - plus others. I've used Grit Guards and not used Grit Guards. I've used a foam cannon and not used a foam cannon. None of these things mattered or caused marring for me. I usually just grab whatever I grab or use whatever I feel like using.
Only thing I consistently do is use good technique, wipe as little as possible, make sure the car is CLEAN before I dry it, and make sure the car is extensively pressure washed before I touch it (regardless of I'm using "rinseless" or conventional wash solution). I'm convinced this is key and no brand of product or special type of product is required to get a good wash that is scratch free.
