08 H3 Alpha Power Steering Reservoir:

[Best4x4]

Does anyone know the size of the O-Ring that goes between the reservoir and pump? My H3 developed a leak on Christmas Day, and I thought I had found the issue, but after a flush of the system along with several days of driving the leak is back. This time I'm 99% sure the leak is between the reservoir and pump. I tried finding the part online, but in the end I found a better deal on the OEM complete pump, reservoir, and cap vs just buying another reservoir.

Besides the leak between the reservoir and pump nothing is wrong with my old unit. I've got to tear into it either way to fix it so that's why I'm just going to replace the entire assembly while I'm at it. I would like to repair the old unit and make it a good working trail spare. If no one knows about the O-Ring size I'll take it apart, match it, and report back.

My P/S needed attention anyways as it was dark with a slight burnt smell. I flushed it good and used some Royal Purple fluid/conditioner so after the leak is fixed I should be good to go.

I've got another question while I'm at it. I've seen those Rack & Pinion aluminum braces for our H3's. Do you have to completely remove the rack to install just the new aluminum bracket? I looked at my bushings and they're in great shape.

 

[Bigunit]

Don't know the size of the PS pump/reservoir O-ring for the H3 Alpha but it's GM part #10388957.

 

[Best4x4]

Sweet thanks! I'll just swing by my local GM dealer and either pick one up or order it.

 

[Bigunit]

If you need the parts diagram for the PS pump/reservoir assemble just Google the GM part number and then click on the Nalley GMC link. Would post the link here but having technical issues with Explorer right now.

 

[Best4x4]

All the part diagrams I found just showed the pump/reservoir as one unit. Then the auto stores were completely clueless. If my wife hadn't been working at the hospital today I would have torn down the Power Steering system, and gone O-Ring shopping lol. It's just a low pressure drip vs a high pressure leak so no big deal until I get the new one in on Tuesday.

I'm having a Magnaflow muffler installed tomorrow (previous owner cut the OEM one off and ran a straight pipe). Local muffler shop is going to install it in place of the resonator, so after that I'll run by my local Chevy/GMC dealer and grab that seal. Thanks again for all the help!