Leaking Hydrobooster in my new 3500 HOHO

[SteelToeStilettos]

Good morning, Fellas,

Well, as luck would have it, the Big Daddy Longhorn I bought for C. Carpenter to drive--2022 3500 HOHO--made a pee spot on the driveway 1 week after we picked her up. Dealer says she has a leaking hydrobooster, and apparently this is becoming a known problem for Star Fleet Stellantis. There was evidence of the red fluid running along the frame and various spots in the engine compartment, reservoir for power steering fluid was very low, and the steering felt quite stiff compared to FH's new 3500 HOHO Limited that was built and delivered at the same time. They tell me the hydrobooster is involved with both the brakes and power steering. I would like to understand all of this better. Your input is always appreciated.

 

[SteelToeStilettos]

it seems that on the 6.7 Cummins, the brake system gets a boost in pressure from the power steering by way of the hydroboost...am I on the right track?

 

[lpennock]

Unlike a gas engine that has throttle plates in the intake that create a restriction that causes intake vacuum, a diesel runs a wide open intake and as such does not pull a vacuum. Brake boosters on gas vehicles use the vacuum on a large diaphragm to reduce the brake pedal pressure. There is two ways to accomplish the same thing on a diesel engine, run a vacuum pump and use the same type large diaphragm as a gas engine or use a hydraulic booster that does the same thing. In our truck they went with a hydraulic booster so a separate pump wasn't required. They just use the power steering pump to provide the fluid pressure to the booster diaphragm.

 

[SteelToeStilettos]

really good explanation. Thank you!

 

[Turbo Terry]

Seems like they have been using hydroboost since 1997. A seal in the unit leaks out power steering fluid. Dealer should make a easy repair under warranty. Many videos of repair on line to watch

 

[gsbrockman]

A friend of mine purchased a new 2022 RAM 3500 DRW Longhorn in November 2021.

Just today he mentioned of lightbseepage that had made it down to the frame rail. His truck is at about 12k miles now.

 

[Cummins12V98]

A friend of mine purchased a new 2022 RAM 3500 DRW Longhorn in November 2021.

Just today he mentioned of lightbseepage that had made it down to the frame rail. His truck is at about 12k miles now.

If it happens to one it happens to many!

 

[Turbo Terry]

Yes I will check mine when I get home. I’m lucky I get to park on a clean garage floor so I can see drips and leaks but in alaska soon will begin the big spring off and on melt so rain and melted snow and slop will be the new normal on the garage floor. Migh be hard to see a leak