Hi guys,
Just had to replace my high pressure steering hose on my 2006 3/4 ton Mega cab. I've bled the system by running the engine, adding fluid and turning the steering lock to lock a few times.

Everything steers great, no leaks, but when I'm NOT turning the wheel there is a "whinning noise" coming from the gear. Almost sounds like the noise you'd get when your at full lock. Pretty sure its not the pump because when i use the stethescope the noise is much louder at the steering gear. It also seems louder when listening to the high pressure hose vs. the low pressure hose.

When I turn the steering wheel the noise is gone, but comes back as soon as I take the pressure off the wheel the noise returns. At fist I thought it was air in the system, but after a few hours of driving I'd expect it to be bled out. Fluid level is perfect.

This one has me stumped. Guessing it has something to do with a check valve or recirculating valve, but don't know enough about the internals of the gear/pump to make an educated guess.

Can anyone help me out?
Thanks in advance.

 

2006 and your High pressure hose broke? WHY? did it break from excessive pressure? It sounds like you might have some sort of restriction going on??
Does the fluid have tons of tiny little air bubbles in it or is it solid red? There shouldn't be any bubbles while looking in..Mome at all.

 

hey ddog thanks.
yes, small leak where the rubber and steel hose meet. wasn't much of a leak, but I was doing a lot of low speed driving around our camp area and probably put a lot of stress on the power steering and it let loose where it was weak.

i don't see any bubbles, but the fluid may have very tiny bubbles in it because it has a slight milky appearance inside the reservior. Very difficult to see for sure. Certainly nothing obvious. I did drain/flush as much of the old fluid before replacing the hose and refilling.

The fact that it only makes the noise when you aren't turning the wheel I find odd. Makes me think something is vibrating when no power assist is required... something like a recirc valve? Something must balance the pressure when your not turning the wheel? Sound definitley is loudest down near the gear vs. at the pump.

Sound isn't a squeal, more like the sound of high pressure water running in a pipe...

 

read a few other possibilities:

I've read about plastic liners inside the high pressure hoses coming loose and making this noise when the wheel is not turned... guess it vibrates when the line isn't under pressure?

Also read about some sort of valve on the pump where the high pressure line connects that could be the cause?

Anyone know anything more?

 

try using a bottle of the Lucas powerstearing fluid, its a bit thicker and seems to quiet things down in worn pumps.

 

thanks Dodgeboy,
if i can't get to the bottom of this i will try Lucas as i've had some success with it in the past on older trucks. in this case i'm skeptical its a worn pump because it doesn't make any noise under pressure and there doesn't seem to be any loss of performance.

something to add to the mix is i've noticed that if the truck sits for a long period 4-6 hours when i first start the truck the sound isn't there. it takes about 3-4 minutes of running before the noise slowly comes back. Makes me suspect i'm drawing a small amount of air in the system some how? No sign of any leaks on the high pressure side at all and the low pressure side looks perfect (and i never touched that side).

At this point I think it is one of three possibilities:
1. Because the noise is coming from the high pressure side when the hose isn't under pressure I suspect the hose could be faulty or a faulty valve in the bottom of the pump where the high pressure hose connects. As soon as the slightest amount of pressure is sent into the high pressure hose the noise is gone. Stands to reason something is vibrating when not under pressure.

2. Air is somehow being pulled into the system on the low pressure side. Not sure how or why it would only cause noise when not turning the wheel... I would think air in the system would more effect steering performance while turning the wheel and less when static.

3. I need to drive down the road swerving from lane to lane like a drunken fool so I don't have to hear this noise.

Last call on ideas before i tear into this??

 

Just to update this in case anyone else runs across a similar problem. What I've learned is this EXCESSIVE "Hiss" or Turbalance sound coming from my steering gear and high pressure power steering line is the normal sound of the turbulance of the fluid around the rotary valve inside the steering gear.

Normally the sound is not excessive.

The fact that the noise is excessive in with the steering wheel in the neutral position (straight ahead) indicates that I may have one of two problems:

1. Faulty rotary valve inside the steering gear (could be some restriction or minor misalignment or ???) Note that the steering performance is unaffected and there is absolutely no noise when I turn the wheel/steering gear.

2. Faulty high pressure steering line transmitting excessive amount of noise or creating excessive fluid turbulance when not under pressure.

Note that this fluid turbulance is always present inside the gear, so the fact that the noise ONLY is excessive when the valve is in the neutral position leads me to believe that it is the change in the gear position, ie rotary vavle, that is the cause. If it was the high pressure line I'd expect it to be more of a problem when under pressure.This logic (or lack of logic) may prove to be faulty though.

I'll update this thread once I determine what in fact the problem was in case someone else runs into the same problem.

If anyone has ideas please feel free to resond.
Thanks

 

If the sound was not there before the hose replacement, and the fluid has any thing other than dark red (NO milky color) than I would say air is still in the system. There is a TSB from Dodge to use only ATF+4 in the system and to use a vacuum pump to purge it of air. Have had to use a similar procedure to cure a GM of power steering noise at idle. There is also a screen in the bottom of the reservoir that can clog with hose inner liner material and starve the pump of volume.

 

Thanks VTWin,
I was unaware of the TSB regarding using a vac line to bleed the system. I have and continue to only use ATF4.

I've bled the system a few times now using the SM procedures... front end on lift, turn wheel stop to stop mulitple time with no engine running. Followed by running engine and normal bleed out.

At this point I see absolutely no air bubbles. My research into this suggests that air in the system would cause more noise when turning the wheel/gear? My noise is exclusive to when the wheel/gear is in a neutral position or under no demand. As soon as you turn the gear the slightest bit the noise goes away (sounds exactly like the sound turning off a running hose).

Also, I've also learned the reason the noise/hiss isn't there after I let the truck sit for 5-6 hours is the fluid is cool. It takes a minute or two for the fluid to heat up enough to cause the "turbulance" or hissing noise.

I'm 100% positive that it is either a faulty gear or HP hose. Hose was aftermarket but looks decent quality. If nothing else presents itself I will probably replace the gear as it seems to be the logical cause... It'll really FRY ME if it turns out to be the new HP hose, but even if I end up replacing both myself it is cheaper than having one replaced at the dealer.

Out of other options that I can find.

 

Sorry, forgot to add that I did check the fluid screen at the bottom of the resevior and it is perfectly clean. I'll see if I can find the TSB on Vac line procedure... is it possible that was more for 1500 with Power steering rack and not the 2500/3500 steering gears?

Thanks again.