Steering box case ruptured! Why?

[aramos3]

Hi,

Just out of no where I loose power steering, upon inspection I find a ruptured steering box. The box was replaced maybe 600 miles ago by a nearby garage. Since having the box replaced I completed a lq4/4l60 swap. What could have caused this to fail? Is there and relevance to the motor swap having an affect?

[kwmech]

I doubt it, just a box whos time was up or was defective. Who knows how many rebuilds there were before you got it

[aramos3]

Originally Posted by kwmech

I doubt it, just a box whos time was up or was defective. Who knows how many rebuilds there were before you got it

That's what I figured, i just wanted to eliminate any possibility the repair shop might come up if the try to act shady.

[toolboxchev]

Over pressure issue, what pump are you running on that engine swap?

Metal Fatigue combine with over pressure and that may be why. That would be a first in my 50 some odd years.

[El Dorado Jim]

Originally Posted by kwmech

I doubt it, just a box whos time was up or was defective. Who knows how many rebuilds there were before you got it

x2

[aramos3]

Originally Posted by toolboxchev

Over pressure issue, what pump are you running on that engine swap?

Metal Fatigue combine with over pressure and that may be why. That would be a first in my 50 some odd years.

I am running the stock pump from a 2004 Yukon Denali.

[special-K]

You'd think the seals or hoses would blow before that. I don't know how many PSI is involved, but I seriously doubt enough to blow out a cast iron case. Probably a mechanical failure, like a part came loose and went were there's no place for it

[Bigdav160]

I suspect it was cracked by someone trying to remove the snap ring on the cover. They might have jammed their pin punch in the hole and were too rough trying to remove it.

[Tom Vogel]

Sure looks to me like it was hit with something.

[mattfranklin]

x2

Originally Posted by Tom Vogel

Sure looks to me like it was hit with something.

[toolboxchev]

Originally Posted by special-K

You'd think the seals or hoses would blow before that. I don't know how many PSI is involved, but I seriously doubt enough to blow out a cast iron case. Probably a mechanical failure, like a part came loose and went were there's no place for it

The mechanical Dark Side of driving. That is a great observation.

[AussieinNC]

The main issue with this failure sounds like the LS pump is putting out too much pressure, compared to the needs of the box itself...these old boxes run somewhere around 500 psi peak...the LS pumps can put out over 2000 psi...especially the hydroboost pumps...

I would be looking at reducing the bypass pressure of the pump relief valve...maybe slowing down the pump...

The failure looks like the assist piston actually pushed the end cap out...metal fatigue due to age, plus wrong pressure...eventual failure...hope this helps...

[special-K]

I can't see duct tape or bailing twine fixing this. RTV?

[Bob B.]

I saw this happen on a Dodge van once. Casting failed, cracked right down the center. Don't think it was a Saginaw box.

I say just one of those things, I can't see how the pump could make enough pressure to do this to a good housing, and I figure the hose would go first as others have stated. Or the belt would slip.