Loss of Power Steering Due to Leaking Steering Rack on Mercedes-Benz ML350

It is not uncommon for the power steering rack to develop a fluid leak requiring replacement of the rack assembly. Loss of power steering fluid may also cause an abnormal noise and damage to the power steering pump.

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Average mileage: 89,028 (31,500–200,000)
7 model years affected: 2003, 2004, 2005, 2009, more2010, 2011, 2013
76 people reported this problem
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problem details
Had to replace the power steering at 59000 miles. Just learned that there was a recall. I was never notified of this by the dealer since I did not own the vehicle when I they sent out notices. So aggravated and seeking recourse.
2004 Mercedes-Benz ML350 78,422 mi,
ML350 made winding sound when putting vehicle in motion. Sound would go away as vehicle sped up, but would return when slowing down at lights or to make turns. Discovered small leak of power steering fluid. First look it appears from the hose and not reservoir.
Noticed leakage on garage floor. Placed drip pan underneath and determined that leakage was power steering fluid. Took to dealer (7th MB, always take to dealer-better results). Dealer said probably steering rack. Options: 1) replace rack, ~$3,000 or 2) install "seal replacement kit", ~1,500. Plan to keep vehicle as has been bulletproof till now. Mech found leak where P/S fluid reservoir attaches to pump and resealed it. Brought home, cleaned garage floor and parked truck. Next day noticed more leakage. Back to dealer. Now mech finds leak at the input shaft on the steering rack, same options. Upon questioning mech says the dealer (small dealership) has done this replacement (option 2) several times and has had no come-back on it so I went with that. Job is labor intensive in that to remove steering rack, the front differential and a support member have to be removed and replaced. Obvious MB knows of this issue but haven't been able to find any MB tech bulletin on it. Update: Vehicle now has 173,000 miles on it. I had the seals replaced in the steering rack. About $30.00 worth of parts but seriously labor intensive-have to remove front differential and other big stuff. Total bill, including 4-wheel realignment was $1,738. Have had no further problem with that in last 43K miles. Did have big issue with torque converter not locking up when it should. Dealer replaced it and flushed transmission about 20K miles ago and no further problem. That burned up $3000.00. Still love the vehicle. Bought new Porsche Cayenne diesel for long road trips, but the ML-350 just keeps on chugging.
2004 Mercedes-Benz ML350 200,000 mi,
My car has been leaking power steering fluid since about 110,000 miles. I now constantly replace the fluid on a regular basis rather than paying the $1500 repair cost.
Just learned that my steering rack is leaking and needs to be replaced. $1500 for the parts plus $600 labor. Called Mercedes, they told me there is no recall on that.
When It moves slow the steering becomes very difficult to steer.
2003 Mercedes-Benz ML350 120,000 mi,
Power steering leak replaced the unit holding fluid starting to leak 50,000 miles later or 2 years.
2009 Mercedes-Benz ML350 71,000 mi,
power steering fluid leak
The steering rack is leaking.
2005 Mercedes-Benz ML350 110,000 mi,
Fluid Leaking, High Pitched noise, poor steering performance.
2009 Mercedes-Benz ML350 77,000 mi,
power steering rack and pinion was replaced 2 year later having the same problem.
2009 Mercedes-Benz ML350 82,000 mi,
steering rack has small leak and requires replacement.
2003 Mercedes-Benz ML350 70,000 mi,
Previous owner had replaced the power steering cooler hose and then 6 months later the power steering pump reservoir at 63k kms. Now at 120k kms the ML350 just dumped the power steering fluid all over the carport when I went to start it. At least I know where to look...
2003 Mercedes-Benz ML350 73,000 mi,
Bought a used Mercedes 2003 E320 and when we took it in for its first checkup at 73,000 miles we were told it had a steering rack leak that would cost over $1,000 to repair/replace.
2009 Mercedes-Benz ML350 122,000 mi,
Power steering leak
2004 Mercedes-Benz ML350 90,000 mi,
The P/L fluid level is low and noice.
2009 Mercedes-Benz ML350 66,700 mi,
Steering completely out at slow speed. VERY hard to steer. Power steering pump and hose replaced. $1600
Replaced pump, still making noise. Now replacing rack because of leak.
2010 Mercedes-Benz ML350 47,000 mi,
Steering became really "stiff". When turning the steering wheel either way, it was hard to steer as if power steering went out. Took it to a mechanic - Rack and pump replacement - $3500! OUCH!!!
2009 Mercedes-Benz ML350 78,000 mi,
Leak on power steering wheel.