Fluid level down on power steering

[VolsFan]

Hi, posted in here a handful of times regarding my dads 03 3500 6 spd.The issue in question now is his power steering pump was groaning in these cold temps and we checked it out and it was low. Found out it took ATF+4. Took about 2/3 quart. Sounds fine now. This truck has close to 400k and is not maintained very well but has had little issues shockingly. Kinda wondering why the fluid level would drop. There are no leaks at all on this truck.
Thanks

 

[Shadrach]

If the cap is not seated correctly it can loose fluid that way. Does it still have the older yellow cap, or has it been replaced by the new p/n one which is black? I have had issues of leaking on my 03 as well. Read the other posts on here and you will find there is an updated pump and reservoir available. David

 

[VolsFan]

Hey thanks! That makes a lot of sense. Yes, it is the older yellow cap on it. The system has never been flushed or anything like that, and it probably never will be! My dad isn't much on preventative maintenance, instead don't fix what isn't broke, haha.

 

[VolsFan]

Shucks,sorry, just saw I posted this in the wrong section, should be in engine/transmission