2nd Gen Non-Engine/Transmission Burped Power Steering Fluid Out of Reservoir Cap?

[DieselDave]

It’s time for my annual cry for guidance from you guys “the Dodge Ram experts”!

After returning home from a recent snowmobiling trip (~325 miles) with my truck/trailer all systems were functioning just great. I unloaded the truck, took it for a wash and then parked it in the garage - again all was good. 1 week later I looked under the truck only to find a pool of oil about 2 feet in diameter. It was definitely power steering fluid. All of the hoses and hose connections look to be in good condition and are clean and dry. No apparent leaking where the pump mounts to the reservoir housing either. It appears to me that the oil came out of the top of the reservoir at the cap!



Before this trip I checked the PS fluid level and found it to be just a hair above the full/cold mark where I like to maintain it. Oddly enough, after the burp the level in the PS reservoir is almost at the top! I had switched out the OEM PS fluid in 2007 @ 233K miles w/ Valvoline SynPower because the brake booster lines were pulsating (Brake Booster Hoses from PS Pump are Pulsating & Noisy ).



At this point I am thinking that I will suck out all of the oil I can from the reservoir and then add Redline Synthetic PS Fluid #30404 which seems to be the popular option from what I can tell and then see what happens. Could I be developing an issue with the brake booster system? What would cause the oil in the PS reservoir to burp out? Is there anything else I should be looking for?



I haven’t run the truck since I returned from that trip a few weeks ago and I probably won’t have time to dig into it for a few weeks but I first wanted to consult with you guys for a diagnosis & repair strategy.



Thanks in advance for your guidance & direction.

 

[RustyJC]

That's a classic symptom of the hydroboost accumulator (the cylinder on the master cylinder brake booster) losing its nitrogen charge. You can check the accumulator by running the truck for a minute or two, then shut it off. Do you have brake assist for one or two applications? If not, the accumulator has puked its nitrogen into the hydroboost system and blown PS fluid out as you describe.



Rusty

 

[DieselDave]

Thanks for your insight here Rusty! I assume that the accumulator is the annodized blue cylinder on the booster housing - right? Can the accumulator be recharged with nitrogen somehow or does it need to be replaced? If replaced - can only it be replaced or does it come as part of a larger system of parts? Is a Dodge dealer my only option for repair or are there better sources? Is this something that I could do myself in my garage or is specialized experience and tools necessary to replace the accumulator? Any feel for cost? Thanks much and sorry for so many questions.

 

[RustyJC]

Yep, the accumulator is the blue anodized cylinder on the hydroboost booster assembly. If you find that the accumuator is the problem, the accumulator itself is not serviceable as far as I know - I believe it takes a nitrogen charge of ~1250 PSIG. You can, however, purchase the hydroboost booster assembly either from Dodge or from the aftermarket - see HERE (note - I'm not recommending this source. I'm just showing what a Google search for Dodge Ram hydroboost booster turned up. )



Rusty

 

[Fireman Dave]

For what it's worth, I had this happen a few years ago. I had to take my daughter to school that day with no PS. Fun! I refilled the PS reservoir after I got home, and I have never had a problem with it again since then. I don't know why it puked that one time, but it's been fine ever since.



Dave

 

[RustyJC]

The power steering and brake boost will function even if the accumulator is blown - as long as the engine is running. Do you have any residual brake boost with the engine off? If not, you're running with a bad accumulator.



Rusty

 

[DieselDave]

So today I finally had time to drain most of the old PS fluid from the reservoir and then refill it with Red Line Synthetic PS fluid. I jacked up the front end of the truck to the point where the front wheels were off of the ground and then started the engine. I turned the steering wheel rack-to-rack about ten times, shut down the engine, refilled the reservoir again and then went rack-to-rack another ten times.



Initially when I started working the steering wheel there was no steering assist but after going just once rack-to-rack it was there again like old times.



I then drove the truck a little and the brake pedal felt a little soft and the steering was a bit noisy. I suspect that this was due to having some air in the system as there were visible air bubbles in the oil at the top of the reservoir. As I drove the truck longer everything became normal once again - the brake pedal was solid and the steering quiet and smooth. Once everything cools overnight I will final adjust the oil level in the reservoir and then keep an eye on it for the coming months.



I still have residual brake boost after shutting off the engine so we are good there. So far so good and hopefully the new oil stays in the reservoir where it belongs now!



Thanks much to Rusty JC & Fireman Dave for sharing their insight & experience with me!

 

[Fireman Dave]

Sounds good Dave!

 

[Hammer]

What you had happen is also a symptom of PS fluid that has gotten moisture into it.



Mine did the same thing a couple of years ago and a switch to a good synthetic and it never happened again... ... ... Andy

 

[GCroyle]

I think a TDR article is due on this topic of the hydro boost, pump, steering gear, the whole system. Expensive parts, IMHO diagnostics are sketchy. This is the first I have ever heard of a nitrogen cylinder.



If it's been done can anyone advise which issue?



How about it TDR?

 

[LandShark]

I have this same burping 'feature' and don't have a hydroboost system. It has happened several times over the years. It has only happened when I was turning the wheels with the engine off (usually with the front end jacked up). I use only synthetic PS fluid.