[Mmusicman]

Well... I FINALLY found my problem!!!

If you've been following me for the past 1/2 year or better... then you know I have been fighting a very serious "over-steering" issue with my 92. On the highway, if I didn't hold the wheel perfectly straight, I would easily get a pretty bad "wobble" going down the road. But the bigger problem was on gentle left turns where it would suddenly and pretty violently over-steer on me, as if the front end was suddenly shifting strong left from under me. Right turns were fine. It felt like the front end had a mind of it's own! This over-steer issue was bad on slow left turns too, like at intersections, where you could still feel it over-steer to the left.

Over time, I have inadvertently replaced almost all of my entire front suspension... with some of them hoping to cure my problem.

Here's a list of all the parts I've replaced:

* New front Moog progressive coil springs
* New upper and lower ball-joints
* New upper control arm (including upper ball joint)
* New upper control arm bushings (included with control arm)
* New lower control arm bushings
* New sway-bar bushings and links
* New idler arms
* New tie-rod ends
* New steering arm drag link

NONE of these parts solved my trouble... but did cure the "highway wobble".

I discovered my body bushings were shot, and the front right size was broke.
I was almost sure this MUST finally be it!
Temporarily "fixing" this did not change anything.

I spent a lot of time doing alignment adjustments as well, trying different things, with no effect.
With my final alignment, I was able to get perfect tracking on the highway.
But none of this solved my serious left-turning over-steer issue.

In addition to almost every part listed (that could be suspect)... along with suggestions of possible alignment issues... it was also suggested my issues could be tires, could be the "rake" (angle my van sits at)... could be the extra interior weight or unbalanced load, or could be maybe just the need for a good rear sway-bar. Of course, most of that wouldn't explain the problem with left turns only.

I started in a fairly logical order (based on fairly logical assumptions). The upper control arm bushing on the PS looked like it "might" be messed up, with some visually separated rubber. When that didn't solve the issue, I figured maybe it could be the lower control arm bushings too, which had never been touched. The ball-joints were sloppy.. sway-bar bushings were falling apart, and the tie-rods and drag link as well as most everything else were all 25 year old factory original parts with almost 300K on them, so it seemed like a good idea to replace them regardless. The springs were replaced (unrelated)... to accommodate the V8. I even had the PS upper control-arm support re-welded to frame in one spot where it looked like it might have been cracked.

Here are some photos of the final and most recent steering parts, the tie-rod ends and steering drag-link.
(most of the other suspension stuff I've already posted)

New tie-rod ends...

New steering drag link...

I finally concluded I had NOTHING ELSE LEFT to replace except the steering gear-box itself! I had previously made "adjustments" to it which didn't seem to help or change anything, which may be in part why I didn't originally consider the gearbox to be the culprit. I also replaced all the other things in order of logic, importance, and least amount of work and cost... so the gearbox was going to be last anyway.

So, I FINALLY changed the gearbox!

I was down to deciding between an ACDelco reman box for about $120 (from Rock Auto) plus shipping, plus shipping the core back... or buying a Cardone reman unit locally from Advance Auto for $100 (after 30% discount) dealing locally with no shipping charges, and no core shipping charges either. If I had a problem with the unit, it wouldn't be a problem to exchange. So I opted for the Cardone unit from my local Advance Auto parts store.

It came in a generic box, with NO Cardone brand markings anywhere on the box or unit.
(I've read that many off-brands are possibly re-manufactured at the same plant in Mexico)

The old unit wasn't hard to remove... had it out in less than 1/2 hour. I did not have any issue separating the drag-ling from the pitman arm (was only about a week old).. the steering shaft removed easily, the pressure lines removed easily, and the main bolts came out easily without removing the tire. Things that made the job easier to get to was loosening the DS idler arm, and eventually removing the battery (should have done that from the start).

I put the old gearbox in the vice to remove the pitman arm (came off easily too with correct tool.. no heat necessary)

My "work-shop" rain or shine: (my garage)

My little helper: (he thinks I put that pad down for him!)

Here are photos of the old gear box gears (showing a lot of wear)...

Note the arrow points to a seriously worn gear spot (positioned in the left turn)
(click photo to really zoom in)

Looking up... It's in! (very easy access)

Looking down... New return line after cross-threading the old one:

New M16x1.5 fitting came with 2' hose (I cut pipe short to fit nicely, see above photo)...

I flushed the system using some very old fluid I had kicking around that I would never use otherwise.
I have never heard of this brand and NO idea how vintage it is! LOL

The idea was to flush the existing "clear" PS fluid, when I see red I know it's fully flushed...
then keep adding new PS fluid until clear again.
It's been several decades since I punctured a can and poured one!!!

Catching the fluid was easy enough (but a little messy when I first separated the line),
using the return line to discharge the old fluid, turning the wheels back and forth,
and cranking the engine a few times too, all while adding new fluid.

Here's my catch setup the first draining and flush...
(the 2nd time I used a large clear jug)

The highway "test drive" was AMAZING!!!
It feels like a NEW van!!
No wobble, no slop, no drifting...
It feels like all new front steering components should... tight and accurate!
I go down the road straight as an arrow and best of all...
The "over-steer" issue is GONE!!!

Here's a video showing the old gearbox.
Note the clunking noise when I turn the steering wheel left, but no clunk straight.
Then you can "see" the play while in the vise:

(I have another minor issue to deal with now and explain, which I will do in the next post)

 

[Leeann_93]

OEM is the brand. They make all kinds of things and make people believe they're vehicle manufacturer parts.

 

[TurnNburn]

Thanks for the helpful and descriptive thread MM.

Extra credit for taking it apart and finding out what went wrong. That is some pretty scary wear in there. No wonder you were struggling to keep that thing on the road.

How many miles on that box?

 

[Mmusicman]

How many miles on that box?

Steering box was original, with about 300K on it.

Extra credit for taking it apart and finding out what went wrong. That is some pretty scary wear in there. No wonder you were struggling to keep that thing on the road.

That was pretty shocking to see how much of the gear was worn down and missing!

 

[1lowcab]

WOW! its a wonder you could steer at all, thats a lot a wear!

 

[Mmusicman]

OK... SO HERE IS MY NEXT ISSUE:

After my 1st highway test drive, I did run into a pump issue... serious at first, then not so much each following run.

Apparently, my first fill DID have some air trapped in the system, even though I did extensive lock to lock purging. I guess I didn't get it all. I hadn't done a "constant fluid" flush yet the first time around (other than blowing the system out), after emptying the system and installing the new gearbox. The new power-steering system worked perfectly and was quiet while cold the first time out, but got noisy and jerky after a 20 minute highway drive. It even locked up on me when doing some left-right testing turns while it was very noisy and hot. After sitting for a short time, it was good again. The return trip home was quieter and better. I even debated on whether the new gearbox could be at fault, but it works flawlessly when the system cools... and I'm fairly sure the noise would have to be coming from the pump itself.

A few days later, I fully flushed the system of the current fluid, and my next highway drive was now much better, but still starting to whine when hot, and causing issues turning while idling and stationary. Again, after sitting for a short time, it was fine again.

I think the problem is I may be over-heating the fluid after a long highway drive, possibly causing cavitation or something like that, from what I've been reading. I'm certain I no longer have air in the system, yet the problem persists... and it's very quiet cold, even hard turning.

To complicate things...I also may have created or increased this problem myself, when I replaced the power-steering pump last year. I did a valve mod (on the reman unit) that increases pressure and flow, and now believe that mod may be causing the system to run hotter than normal. It's only a small increase in pressure, but that could potentially be enough to cause a problem.

Apparently however, the "noisy pump after heating up" issue is a fairly common problem too.. I found much talk on the web about it, even under normal conditions.

There is also a lot of debate on which PS fluids are better for addressing this issue... ATF vs PS fluid vs Synthetics.
Seems most have gone to synthetics with varying degrees of success with regard to this issue.
Of course, the old schoolers just say put in whatever the manufacturer calls for.
Ironically, some manufacturers call for outdated ATF Type-F over PS fluid... but it's hard to get a definitive answer as to why.
That was also a long time ago!

Most people in general suggest however, the addition of a PS cooler...
claiming even a small one should be mostly helpful.

Here are the 3 things I plan to do next:
* I will be adding a new PS cooler (already purchased)
* I will be changing to synthetic fluid
* I will attempt to change my pump mod back to original

I hope to do this when I get home tonight.

I have a couple quarts of "Royal Purple Synthetic PS fluid" I acquired a few years back.. I will try this.
The PS cooler I picked up is a typical single pass tube/fin type.
The valve mod was just the removal of a shim to increase pressure which I can put back in.

I won't know which of these 3 changes will hopefully "fix" my problem... as minor is it is.
But hopefully these changes will work!
We'll soon see...

 

[AstroWill]

Glad you got it fixed. That is a LOT of wear, did you ever have someone adjust it, maybe they over adjusted it.

 

[Mmusicman]

Glad you got it fixed. That is a LOT of wear, did you ever have someone adjust it, maybe they over adjusted it.

That's a GREAT question! (I've even asked myself that)

It was never adjusted from the original factory setting for several decades... until sometime last year when I attempted to make a re-adjustment. I had replaced a leaking steering shaft seal at the time... and figured I would see if I could make any further improvements. My attempt did not help anything... but I suspect it possibly did make things worse, even though I returned it back to it's near original position. I just couldn't adjust the play out of the turn, but straight away was no problem. All the other worn steering components may have added to the problem as well.

I am aware that these gearboxes can be damaged fairly easily if adjusted incorrectly, but I was careful to stay within setting procedures. None the less, the damage was probably already there, and I probably may have made it worse. It's hard to say if the specific previous gear wear was already there.

 

[TurnNburn]

All of the astros I have driven all have pretty noisy power steering pumps. Mine is pretty loud. When I swapped out all of my fluids I put the bulk atf in it that we have at work. It is a synthetic atf made by valvoline. For what its worth, it didn't change the noise at all.

Also, just thinking out loud, could that ancient atf you put in there be at fault as well? Have you tried swapping in some known good fluid?

 

[Mmusicman]

Also, just thinking out loud, could that ancient atf you put in there be at fault as well? Have you tried swapping in some known good fluid?

Funny... I thought about that too! :shock:

I thought I was being clever wasting fluid I would never use.
But that ancient fluid was pushed out by new PS fluid when I continued the flush... so it should be long gone... well hopefully MOST of it! lol

My issue DID improve afterward... just not completely. What's in there now is still just temporary.

But I am planning to change the fluid out completely (again) when I install the PS cooler, adjust down the pump pressure valve, and switch to the Royal Purple Synthetic. The vintage fluid should be doubly long gone by then! At least I don't have to look at the can sitting on the shelf anymore!

I'm not convinced the synthetic will make much difference either, but I'm guessing it can't hurt. That along with the other changes...

PS: I do have some vintage Valvoline ATF in a can too... I'm saving that for the next special project! Doh!

 

[WoodButcher]

I finally concluded I had NOTHING ELSE LEFT to replace except the steering gear-box itself!

:rofl:
What took you so long? lol.
I'm in the same boat but far from sinking, 150,000 miles I still have a bit left. When I did the motor swap I checked the gearbox while the steering was apart and found more play than I liked but funds were tight so I let it go. It's still way down my list to do.
Sounds like your on the right track chasing the gremlins, keep us posted, thanks!

 

[timothy47130]

As funny as it sounds I have found some power steering pumps operate quieter on power steering fluid and others operate quieter on atf. I flushed mine out with power steering fluid and it took about 5 quarts to finally get it clean. You wouldn't believe how nasty and burnt that stuff was At 120,000 miles.

 

[Mmusicman]

UPDATE: Ok... hung out with my little buddy Sylvester again today on Father's Day. Flushed and changed the power-steering system with synthetic, changed the ps pump pressure valve back to stock, and installed a power steering cooler.

Here is the new cooler. It is quite small, easy enough to install and tuck anywhere,
came with a lot of hose, and after discount cost me a whopping $14 total from Advance Auto.

Simple mounting.. I intentionally kept it away from everything else:

Mounted in open area between grill and bumper:

Here is the easy and simple hose routing:

There was a little more of that "vintage ATF" still in the system than I expected. This time, all was completely drained when I removed the high-pressure hose and valve from the back of the PS pump. The system was thoroughly flushed with numerous quarts of clear PS fluid... then I continued flushing through while I added a couple quarts of Royal Purple Synthetic to complete the job.

Performed numerous lock to lock procedures to purge the system of any trapped air while flushing the system. Performed numerous additional lock to locks after system was closed up.

The other part of my project was to undo the pressure mod I did to the PS pump.

Here is a photo of the valve mod on the PS pump:

The left valve is stock (note the washer shims) ... the right valve has the shims removed to increase pressure. The difference is supposed to be from about 1100-1200 (stock) to about 1350-1450 (with mod). I put the system back to stock.

Here is a photo of the other mod I'm undoing, where slightly enlarging this hole increases flow. This, along with the pressure mod can really give the PS system a boost... but apparently it may have a side-effect of increased heat as well.

These mods just aren't necessary on a street machine. I originally tried it because I was having issues with the power steering not working well after it warmed up. This mod wasn't really necessary.. the trouble was probably just with the old gearbox.

It is uncertain if this mod was causing any of my current issues or not with the new gearbox, but I decided putting the system back to stock should be more than adequate. It should be noted however I did the same pressure mod on my 2000 AWD's new ACDelco pump, and it performs flawlessly... the hydro-boost brakes love it and work much better too.

Well, that's about it for now. The test drive around the neighborhood was completely quiet and perfectly smooth as expected. Unfortunately, I won't be taking a highway drive until next weekend to see the final results.

I'll post the results then.

 

[WoodButcher]

Brought this over here-

MM, didn't your van start life w/ a PS cooler? the naked tube stretched across behind the front bumper?

NO... NEVER had a cooler.

Reason I ask is both mine have a cooler of sorts, just a 3/8" steel line bent to a "U" and shaped to fit in front of the lower core support. Not much but maybe enough.

DSCF3426

• WoodButcher
• Jun 19, 2017

I'm pretty sure my '97 has it too, could be why the pressure mod worked on your gen II and not the '92?
Pressure = heat = cavitation?
Does your '92 have the brake booster? Both mine do but the gen II stinks, when braking into a hard turn at low speed, low idle, it falls on its face. Did this happen in your gen II before the pressure mod?

 

[Rinny]

MM this is a great thread. When I bleed my system out if I run into any problems I will know where to look. I scanned it over rather quickly but when I have more time it will be a great read. Thanks for taking the time to do the write up.

 

[Mmusicman]

MM this is a great thread.....Thanks for taking the time to do the write up.

You are welcome... thanks for the reply! I almost deleted some of it. I was starting to think I might just be "over-rambling" about non-sense... but hey if I'm having issues, then maybe someone else is having the same. If this helps one person, or even just steers them in the right direction, then all the posting and effort was worth it. Good luck.

 

[Mmusicman]

Reason I ask is both mine have a cooler of sorts, just a 3/8" steel line bent to a "U" and shaped to fit in front of the lower core support. Not much but maybe enough.

Yes, I actually saw that about the u-shaped cooler pipe! In fact, it was very confusing to me at first, because all the return lines I kept finding indicated they were connected to a cooler which mine didn't have. I couldn't find a return line that matched mine.

Since I installed the aftermarket fins/pipe cooler, I wondered how they compare with the stock "factory" cooler. I expect that the aftermarket unit, as tiny as it is, should be somewhat better at least, since it is in direct airflow with cooling fins.

Here's a photo (not mine) of my factory return line (which has been discontinued and no longer available). They want like $50 for this exact GM part. The short rubber line (not shown) connects directly between it to the PS pump return. Even repro does not even remotely match this shape. You can buy a simple 90 degree fitting (for $5) and use a slightly longer rubber hose. I bought the $15 part with more pipe angles, and wound up cutting them off anyway.. lol

I can NOT actually find a factory "cooler line" for a 92.
The one in this photo is for 95-05:
(maybe it would fit?)

Pressure = heat = cavitation?

Yes.. that is exactly why I think I was currently having issues with my 92 and the new gearbox, and is the reason I undid my modification. Remember, it was initially an attempt to fix a steering issue after it got hot with the old gearbox.. and it probably just made things worse anyway. But I didn't have cavitation with the old gearbox... just the new. Perhaps tighter tolerances in the new gearbox raised the pressure enough to cause my new issues.

Does your '92 have the brake booster? Both mine do but the gen II stinks, when braking into a hard turn at low speed, low idle, it falls on its face. Did this happen in your gen II before the pressure mod?

My 92 has a vacuum booster, which doesn't do very well with a heavily cammed hot-rod engine at low speeds. My wife drove it and it freaked her out (but she told me she sure liked the looks she was getting). I'm strongly considering my need for an aftermarket "vacuum reservoir" for the brakes. The brakes are fine on the highway.

My 2000 has hydoboost, and the brakes were kind of weak. The pump was very noisy from the day we bought the van, and no amount of flushing and purging would help.. I suspect the pump was damaged. When I installed a brand new pump, I did the pressure mod, even though I have no idea if it would have been fine stock. Regardless, it works GREAT! The steering is powerful yet quiet, I have no cavitation or heating issues, and the hydroboost never worked better! Again, I can't say if the pressure mod actually helped, or if it just works great because the pump is new.

 

[Mmusicman]

UPDATE:
Well, the final operation was 100% SUCCESSFUL!!!

After installing the little PS cooler, flushing and filling with synthetic, and restoring PS pump pressure valve back to stock... I now have 100% smooth and quiet operation! There is no change after coming off highway either.. I now have full smooth operation when the system is warmed up too.

Steering with new gearbox is a dream! It's tight with NO play.. and goes exactly where I point it. No wobble on the highway, no more over-steer in corners. With all the new steering and suspension components along with a meticulous alignment.. it drives like a new van again! Woo-hoo! :mrgreen:

Driving home last night was great however... UNTIL I blew ALL my forward drive (while shifting) after coming off the highway. I coasted into a neighborhood close to home, and called the wife with my other van and a chain for a tow home. Ironically, I still had reverse, which let me maneuver into a good spot to wait. The tow home went smooth... I backed it into the garage and called it a night!

Looks like today I will be pulling the busted 700R4. I knew this day was coming. I'm also looking into using a spare trans in the meantime while I rebuild the 700r4, an almost like new TH350 (with shift kit and new stall converter) I have sitting around.

At least I'm done with the steering!!! :shock:

 

[WoodButcher]

Lol, it's funny but it sucks.
I sometimes wish I could be happy with a new car that I could start up and go every time but it just isn't me. I got the wife a '13 Subi forester and we both love it for much different reasons. I like it because all I need to do is basic maintenance and I can turn my back.
Given the choice between that subi and your broken van? I'd take the '92 any day... :rockon:

 

[Leeann_93]

Yes on the PS! :driving:

Sorry about the tranny, though