Grease removal - underbody cleaning

[schwag9AWD]

I have some grease/dirt caked under my car between the drip edge and frame rail area from my door almost back to the rear wheel on both sides of the car. I'm not sure exacltly what it is because its been there since I bought the car....

So far I have tried using some cheap Engine Degreaser....letting it soak, then spraying it off....this didn't help much until I used a wire brush where I sprayed, but it still didn't fully come off
Next I tried a high pressure washer at a car wash, but it only removed some of the grease, and took a long time.

What other products, or ways should I try to get this off, I've heard GUNK works really good on engine bays, but this stuff is caked on pretty bad.

 

[Defiant]

Is it grease, or undercoating?

 

[schwag9AWD]

It looks like grease to me, also the last owner lived on a dirt road, so maybe it's mud built up too. I can rub it and some will come off on my finger. ?

 

[biddybengbeng]

wd40 works wonders

 

[TurboBlue]

even if it is undercoating, just get a nice heavy duty scraper, not like a putty knife but a nice Mac Scraper, and just scrape it all off. then either re-undercoat it, or buy some Por-15, awesome stuff, its a black paint that just does wonderous things, protects like undercoating without the texture, just wear gloves, the only way to get it off, is to let the skin just fall off over time...

 

[schwag9AWD]

Thanks for the info, I'm gonna try it this weekend