undercarriage wash question

[Sumrtime]

I realize this may be a dumb question but I'm gonna ask it anyway.  Is it safe to use an undercarriage attachment for a pressure washer under these trucks?  Not gonna blast away at 5,000psi. just want to give it a thorough rinse after being at the beach for a week. Curious about any risk to any of the sensors etc. in the DPF exhaust system. Or anywhere else for that matter. 

[gemarsh]

Nope. I would recommend to let truck to cool down some before blasting it with cold water.

[Another JR]

The vent for the rear differential opens in the area of the fuel filler neck. The vents for the transmission, transfer case, and front differential all are routed to high points but I don’t know where. It would be good to know where they are and not spray there. 

[Pryme]

Anyone who has driven down the freeway during torrential rain knows the undercarriage gets hammered for as many miles as you’re driving. Probably not gonna have an issue. People don’t let their car cool down before going through a car wash that sprays the underside of the vehicle. 
 

I only wash my vehicles by hand for one because I enjoy it and two I’m way too cheap to spend 10 bucks on a car was. Especially here in the Midwest it’s dirty in a few days anyway. 

[gemarsh]

1 hour ago, Pryme said:

Anyone who has driven down the freeway during torrential rain knows the undercarriage gets hammered for as many miles as you’re driving. Probably not gonna have an issue. People don’t let their car cool down before going through a car wash that sprays the underside of the vehicle. 
 

I only wash my vehicles by hand for one because I enjoy it and two I’m way too cheap to spend 10 bucks on a car was. Especially here in the Midwest it’s dirty in a few days anyway. 

Usually they keep the engine running while going thru car wash. Keeping things hot.

 

But then again, us in the midwest will have a at temp vehicle and blow thru a snow bank. That is extreme. So maybe I am over thinking letting the cat cool down before dowsing it with cold water.

[KARNUT]

My car wash does underneath. In beach areas underneath rinse is common. 

[Pryme]

8 hours ago, gemarsh said:

Usually they keep the engine running while going thru car wash. Keeping things hot.

 

But then again, us in the midwest will have a at temp vehicle and blow thru a snow bank. That is extreme. So maybe I am over thinking letting the cat cool down before dowsing it with cold water.

No I get what you’re saying and it probably is best to let things cool. I mean I sometimes spray off the lawnmower after a really messy or dusty cut but I always let it sit before I do. Just cheap insurance 

[gemarsh]

In the old school dayz, it was a known fact, if'n one was to take freshly installed glasspacks and hot rod for a few miles to where they were cooking, stop and shove a garden hose in the end quickly, you'd "break" them in quicker!