I recently purchased an 01 6 speed single cab Cummins. I’ve noticed that while driving at slow speeds and turning the steering wheel the truck makes an aggressive power steering whine type noise and vibrates the truck like it wolf off the pump was low on fluid or something. Only while driving at slower speeds, making turns in town and such. Here’s the interesting part, if I’m mid turn and it’s whining, and I press the clutch in it goes away and won’t make any noise. If the truck has either the clutch pedal depressed or if it’s not in gear at all it doesn’t make a sound while turning but If it’s in gear, it makes the noise. Doesn’t seem to matter if I am on the accelerator or not. The part I don’t get is why does it only do it while turning, that makes me think steering, but pushing the clutch in makes it go away? What could it be?

What is the condition of the power steering fluid? (Amber or black)

 

When was the last time you flush the power steering system? (Every 30k)

 

Are you using Power fluid and not ATF? (DO NOT use ATF)

 

Is the power steering fluid foamy when its whining? (Possibly low on fluid)

 

As for my comment on flushing this means removing the steering box return line from the pump and route it to a waste bucket. Plug the nipple on the reservoir to allow it to hold fluid. Now with the front axle off the floor and Engine OFF key to unlock the steering wheel. Now go from lock to lock slowly. This will pump out the system. When empty fill another 3 times and pump through till the fluid is clean. Then rehook up the return line and fill. When you start it will foam up. Shut down and wait for the foam to settle about 15 to 30 minutes tops. Then top off and you should be good. 

 

Do NOT use a turkey baster to suck out the reservoir. You only getting about 1 pint out. The entire system can hold nearly 2 quarts. Steering box allow holds about a quart to itself.

Edited September 25, 20204 yr by Mopar1973Man

I will have to check. Wanted ideas on where to start before I dug into the wrong areas. I’ll check the fluid when I get home from work and inspect the color and level. I just bought it so I’m not sure when or if it has ever been flushed. I’m guessing probably not. I will flush it if that will help my problem. Just wanted to make sure it is something power steering related. 

Typically power steering fluid is a forgotten fluid no one changes. 

 

As for the clutch part. If the clutch is playing a role in noises it could be a throw bearing or pilot bearing. Typically they make noise if you press the clutch down. Like I've got a 2006 in my shop with blown throw out bearing and pressure plate fingers are worn. Every time you touched the clutch pedal it would scrap and grind noise. Let go typically the throwout bearing is just touching the finger but not seriously loaded. 

Pilot bearing will make noise typically when you foot is on the pedal being the input shaft is not moving or moving a different speed than the engine now that bearing will make noise. Typically pilot bearing will make it hard to shift gear either up or down. 

 

The only other subsystem is the vacuum pump but that is lube by engine oil. Never heard of a vacuum pump making a whining noise. It forward of the power steering pump. 

 

Like myself I've got 421k miles on my OEM power steering pump and never replaced it yet still working as designed!

It is a stereotypical power steering pump sound. Just odd that it only does it if the truck is in a gear while turning. Pushing the clutch in isn’t the only way it stops it, just one way. If it’s not in gear at all it won’t make the noise no matter how much I turn the wheel. For some reason it seems the rpm and slow speed of the vehicle at that time must put more stress on the pump? I’m hoping it’s not failing. Hopefully some fresh fluid can elevate the problem for me  

Gotta ask do you have over sized tires on the truck bigger than 265/75 R16? Larger tires do put a huge amount of strain on the steering box. Makes it worse if you have a quick ratio steering box and over sized tires. Like Ryan at Blue Top told me if your running smaller that stock tires (265 or smaller) you can run a quick ratio box. But if your going to run over sized tires (265's and larger) you need the standard ratio box to lighten the load of the steering gears and hydraulic pump. 

 

Edited September 25, 20204 yr by Mopar1973Man