We have just purchased a used Ford, E450, BigFoot, 2002, Class C, motor home with the Ford V 10 engine. It has the Banks Power Pack intake/ headers package and while I was servicing the K&N intake filter I looked down through the small opening at front of the engine intake manifold that’s sits above the engine “Y” area where there is a large space under the manafold and much to my dismay found a large rat/ desert pack rat nest. The motorhome came from Los Vegas and I purchased it in Northern Cali. That large straw filled nest has been in there for a questionable amount of time and it is a wonder that the engine heat driving up from Vegas did not start a fire.
I had to take off the back engine dog house cover and use an electric leaf blower and a stick to probe the nest from the front and back of the engine to blow all of that straw/poop out of there,….what a mess.
Take a look at yours as you might have a surprise.

 

rats are a pain around here I always make sure they don't get any of our trucks. If your truck is rarely used keep the hood opened under a canopy or something they are scared of light. Also if you don't have a canopy if you really care for your van/truck then put a light in thier you just take out when ever you drive it. If you drive it reguarly they usually won't hurt your truck.
Trav

 

I had a TON of lady bugs or Asian beetles in that same area on my truck. No damage, and they were well cooked, which made cleanup easy, but its definitely an area to keep an eye on. My truck is driven almost daily, it doesn't take long for something to take up residence.

 

I was there when a buddy installed a blower on his Marauder. He had a nest in that area. I would assume since vehicals that sit for a good period of time would be the most likely to get critters up in there, but not nessisarily.

I'd suggest also looking in them large drain holes at the rockers. Especially with running boards. I had birds make a nest up in there. Well it collected moisture and eventually rotted out a cab corner. I never seen it because the steps covered it pretty well.

 

I actually had about 30 acorns in my air cleaner box from a chipmunk i assume, man what a tight spot.