I would like to clean the undercarriage of my '04 RX330, especially around the gas tank and rear shock area. Can anyone recommend a good cleaning product for this?

 

P21S Total Auto Wash with a foaming sprayer. Its paint safe too in case you hit the car with it. If you want something cheaper I think Optimum Power Clean with a foaming sprayer works well too. Both can be purchased from any of our Detailing sponsors. Of course, if you have a Harley Davidson shop by you, "S100" is the P21S brand relabeled. Its cheaper than P21S by a bit iirc

 

I would use a power washer, with diluted de-greaser 50-50. I have always wanted to do this. Get it up on stands and go for it.

Would have been nice if you had a lift....!

 

I use my pressure washer with APC. Works very well with a right angle tip.

 

That's pretty much the way I do it on my RX300.