Its pretty exposed there. Water/ dirt/ grit are all bad for compressor, as are rock impacts lol.

 

Try to mount it upright if at all possible. Everything has a weight associated with it, and since you can't overcome gravity... one side of the piston will wear out faster than the non-weight-biased side.

Also remember that the head of a compressor looks like a heat sink why? -Because it dissipates heat. It becomes far less effective when on its side (or upside down... - a definite no-no).

 

Not if you relocate your air filter. I always recommend that people plumb it into their air intake box... with the filter attached. Its doubly filtered and will never take in water or debris.

Just make sure that whatever compressor you're using, is sealed!

 

In a V6 4runner space is definitely an issue - especially if you already have a functioning AC unit and don't want it inside for the noise factor. Several people around here run twin self leveling suspension pumps out of a Caddy. I think those might be next on my list since I can't cram my york under the hood.

 

If you can find 'em, 4Runner's came with rear bags in their 4th generation on certain suspension packages. Be nice to keep it all Toyota . I had one that I pulled out at the dealership due to a faulty vent solenoid (built in). I made it into a portable toy filler for air mattresses, balls, etc w/a cigarette plug. Good volume output, fairly quiet, and built to be frame mounted.