Hey folks. Just bought my first Chevy as a work truck the other day. My crew drive it daily pulling about 6000 pounds in mowing equipment. The truck is a 2005 Chevy 2500 with the Vortec engine. It only has 28,000 miles!

Anyway, the truck was immaculate, very good shape. However, I did notice some oil buildup underneath the drivers side fender, so I popped the hood and found a few oily areas by what I think is either the power brakes or power steering module (maybe they are the same thing). There was no fresh oil, but there was some residue from dust stuck to where oil had probably been fresh within the day. Below the module, I can see where something has been dripping down to where it was showing on the outside of the fender. Can anyone help identify this and whether or not it is immediately serious? Seems like it's a really slow leak. I have posted pictures.

Photo 1 is the module that I presume the leak is coming from. It had oily residue on it but I couldn't see where any oil would be coming out of.

Photo 2 is looking down below that module, you can see where a few drips have landed and rolled down the inside of the fender.

Photos 3,4 and 5 are looking at the oil residue from the drivers side fender.

Thanks

 

I can't tell much, but, thanks for the photos !

You need to start from scratch...
Get by a Hi-Pressure Car Wash and give that area a squirt from all sides till it's completely clean.

THEN, do frequent inspections to catch the leak as it just starts to wet the area again. Keep in mind, that the Fan is going to try to migrate that oil, so watch careful, and take the air flow direction into consideration !

 

Look inside the truck under the dash where the rod to the brake pedal comes through the firewall. If it is wet there then the hydro booster is what is leaking. Very common problem, leaks under hood and under dash

 

There is a fairly common leak between the hydroboost assembly and the brake master cylinder. They used to sell rebuild kits to reseal them. But, that is no more and the only fix is a new assembly. Most of them have some residue around the "weephole" on the bottom even if they are not actively leaking. But active leaks tend to progress fairly quickly. It is usually anywhere from 6 months to a year after I notice one of these issues on one of my customers trucks until it becomes a very active leak if they haven't repaired it yet. Although some have lasted quite long with only the occasional drip. It is not difficult to change on the trucks if you are flexible enough to operate under the dash. But, I would price it and keep that number in mind. If all the fluid leaks out you loose brake assist and power steering.