I recommend the steam cleaning service at Deluxe Detail and Tint in Mesa. I first took my truck there almost 15 years ago prior to painting the undercarriage and went back there a few months ago for a refresh. Same owner after all those years, which I appreciate. They'll put your truck on a rack and melt that grease and oil away. I splurged for both the undercarriage and engine detail, which was $120 with website coupon. This was prior to a birfield job and a power steering pump rebuild, so it was nice to work on clean parts. Afterward I touched up the frame, axles, and wheel wells with a fresh coat of spray paint. Good for another 15 years (at least here in Arizona).
Warning - engine porn below.
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