Dropping and replacing subframe

Might as well start a build thread for this work. Will be spotty at first, as I have zero experience posting information like this, but this may prove useful for others who will be doing some of the work that this involves. I'll be primarily replacing the subframe because of rust issues, however I'll also be recovering/repainting a lot of the parts associated with the suspension, as well as doing an overall engine dressup (painting plastic bits) as well as replacing the fuel pump internals. Lol, wish me luck.

Picture of the initial suspension, rear LCA and spindle on the drivers side, with some of the subframe in the back. I'll have to put in a pic of the area of the sub that's the major concern, think it's the LCA attachment on one side or the other. The caliper bracket and coil supports have been soaking in metal restorer for two days, then hit with steel wool, 80 grit sandpaper and a wire wheel on my drill. I'm going to apply some Corroseal to these parts and allow that to hopefully neutralize whatever rust is left, then paint all these parts. That's the plan for all the parts of the suspension that I pull off as well as the brakes. If you look close at the separated ball joint, you'll be able to tell that I should have waited for my ball joint kit to arrive before attempting to get that one off. I'm assuming that part is threaded ahead of the boot, so all I'll have to replace is the front bit.

Looking for some recommendations on paint for the suspension parts and brakes, anything anyone has used that has proved both durable and provided an easy surface to clean would be appreciated.

 

POR15 is good for suspension rust removal and coating. I have seen that used before.

 

I read a thread on someone's 3 who had used the Corroseal to arrest the rust, even worked on the rust under the paint, so I ordered that product for the rust inhibitor. Haven't decided on what paint to use yet, figure for the suspension parts it doesn't have to be high temp, while the brakes will be. Like to do it all in one color, but that might not be possible if I mix the paint types.

 

I had some parts sand blasted and then I did por15. It worked really well but it is no UV safe so don't put it on parts that see the sun. It is a decent amount of work to apply as well.
https://mazdaspeeds.org/index.php?t...-build-maximum-carnage.7025/page-9#post-69616

 

Back on topic, since I haven't pulled the LCA's yet, what's the life expectancy on those? Watched that 1A auto vid on the base 6 and the ones they pulled off were pretty shot, but they didn't give the mileage on the car. Thinking that the noise in the front end of my 2010 might be coming from those, as it has 105k on it now.

 

Corroseal came in today, this is the after pic of the caliper bracket and strut supports. According to their website, this is exactly how they are supposed to look if done correctly (all black, no streaks or imperfections). The reaction was almost instantaneous, and this is a primer so when it’s cured I can simply paint overtop of it. This product gets a thumbs up for ease of use, let’s see how well it holds up in a year.

This is what is behind my wheel well liners. I wasn’t sure what I was going to do here, but I’m sure that a quick wire brush followed by a Cooroseal treatment will get these areas ready to paint.

 

The undercoating is peeling off and there is a good deal of rust most likely underneath what you can't see. Get a solid rust remover chemical and let it saturate the area. Then hit with a wire brush, then protection coating then paint/undercoating.

 

Should I try to get that undercoating off?

 

Started removing the undercoat on the drivers side to see what the metal underneath was like. First pic is back by the door, looks like surface rust without any places eaten through. Same with the strut tower, front of the fender and up by the bumper. Lots of rust, but manageable. Going to pull the spindles this weekend, which will make this job much easier.

 

Awesome stuff dude! Glad it isn't horrible rust but you'll be properly preventing future issues.

 

Shout out to you for drawing this to my attention, I would never have thought to strip the undercoating off the car. Going to be a tedious process, but well worth the effort. I've been reading up on that POR 15, that does really seem to be the stuff to use up in these wheel wells. Expensive, but again probably worth the price for the benefit. I'll probably put it on my new sub also, can't hurt to give that some more anti corrosion properties.

 

Is there a harbor freight near you? I recommend buying they master Metric Tap/Dye kit. I have it along with this style tap socket set

Lisle 70500 Tap Socket Set

https://www.richtoolsystems.com/45-...WzMVtLjhv4KSSBs2T8IiwtgBnbkc9uhIaAtldEALw_wcB

Definitely use this to clean all your threads after coating. You'll be amazed at how easy the body panels and suspension components bolt into place afterwards. That master tap kit has sizes all the way up to axle nuts which is a bonus. Make sure you purchase the metric one as the SAE and metric sets have identical containers

 

I'm praying I won't need these, but good to know about them. I don't have much experience with removing rusted bolts, but I think that's about to change, lol.

 

This will be your new best friend.

https://www.homedepot.com/p/Bernzomatic-TS8000KC-Premium-Torch-Kit-336638/205683985

I use one at work all the time even with some non super rusted parts like exhaust bolts etc. A few seconds of heat and it helps them break free.

 

Lol, yep, I leave that in the garage now.

 

Driver’s side steering knuckle is out, paasenger’s side nut is off. Had a 1inch ID conduit three feet long with my craftsman 1/2” breaker bar on the passenger nut, with me bouncing on both of them. Heard a crack, thank god it was the nut braking loose. Gonna strip the driver’s side wheel well, then do passengers side.

Coming off much easier than I thought it would. Heat gun and scraper first, then wire wheel on drill.

 

So all told today I have about 1.5 hours doing this undercoat removal, and I’m 1/2 hour from being done. Physically I’m done, but I’ll have the last bit off tomorrow. I thought this job was going to be a bitch, but it was actually not that bad. Boring, but quick and easy. You can see all the rust up in the strut tower, I’ll be treating that with the POR. All the little bits of undercoat will come off when I figure out which solvent will dissolve it. If you’re going to pull the suspension off and you have rust, I would seriously consider doing this work. Again, thanks to L337 for the heads up on this.

 

Well, this sucks. Upper bolt for the fender stripped.

 

Do you have a solid set of stripped bolt sockets? I recommend these


I have used them and now have a full set of the shallow sockets which are supposed to do metric and standard (which I am pretty sure I have had zero failures of removing stuff with) and a deep well set that is only 4-5 sockets. I bought mine at the local autozone parts store but these on Amazon seem to give you 9pcs for $50 which is great!

They are somewhat pricey with 4-5 sockets being like 40 or 50 bucks but they are amazing and if I even think it is going to be an issue I just use these before a regular socket. This prevents mostly all the issues I am reading that you're having. Just use kroil penetrant ($20 a can)



and then heat after it sits a while. Then, use the special sockets before stripping with a normal socket and it will most likely bust it out man.

This the best method I have found by far! Hope these tips are helpful for you man and I know this stuff will be a bit up front but you will seriously be surprised what this stuff does compared to even other products that appear the exact same.

 

Thanks for the heads up, like I said earlier I don't have a lot of experience with rusted bolts this bad. Usually the car is gone before it gets to this point. I like tools, so this set is on the buy list, lol. Do you think the Kroil is better than PB blaster? I'm using that, not sure how much it helps, but it's always been my go to penetrant.

I did manage to pull the fender off last night, finally. 10 minute job turned into a hour of using a hacksaw blade on that bolt, ffs. I've also sent a some pictures of the interior of the wheel well to POR support to get their opinion on how much more work I need to do prepping the area, or if they think it's ready to go. I'll post them later on today with their reply.