Does anybody have any advise or best practices on cleaning up the grime and build up from oil leaks under the engine and transmission? I'm talking about the thick buildup.

 

Take your ramps and lots and lots of change as well as a bottle of Krud Cutter to the DIY carwash.
Run the front wheels up onto the ramps, spray the underside with your Krud Cutter and let it soak for 15 min.
Then use their degreaser and hot water to wash the junk away.
If you do this in your driveway then all of the grease and oil will get into the ground water and your driveway/yard will become a Super Fund site.
The carwash has oil-water separators and it will be properly disposed of.

 

unless you plan on or have already fixed the leaks I would recommend you leave it, it acts as a sponge and seal for small leaks, if you clean it small leaks may become bigger leaks.

 

It all depends, a thick layer of gunk and grime holds the heat in the block a lot longer as well.

I spray simple green or a similar dollar store degreaser on it straight several times, then do what Spike says minus the ramps. The car washes around here don't want you tying up their boothes waiting unless you are pumping quarters in the machine, so I spray it heavily before I get there.

You need to be careful about getting the ECU wet, it will barely run if you get the electronics wet, I find out the hard way myself.

 

If it's REALLY thick, then I'd run it up on ramps in your driveway and clean the big stuff with a putty scraper. Then some morning, I'd spray with Gunk Engine Degreaser and let soak for hours. Then spray again several hours later. After a couple hrs, take it to the car wash and do as Spike indicated. It'll be as clean as a whistle.

 

Cool, whats guys, I appreciate all the great advice, I will definitely look into doing that on a day that I'm off, and the putty knife gunk scraper is also a great idea. I just want to get it all cleaned up and see if I have any leaks that I can attend to.

 

I wouldn't use any cleaner on it. Simple green at the most. High pressure spray works wonders..

Also be careful around the ecu (by the washer bottle)