Vehicle in discussion: 2000 Excursion Limited 7.3L 4x4 (216K miles)

So I bought my Excursion around this time last year and could tell that the power steering was going to need some lovin down the road….well the time has now come and I could use a little help with where to start. When I bought the truck, I noticed that the power steering was a little weak and tended to “wander” slightly and higher speeds. I was able to drive the X without much problem (the only times I really complained about it was while backing up trailers) and the wandering wasn’t terrible, but it was there. At the time, I was dealing with the dreadful Excursion windshield leak which was dripping water down on the GEM which was causing all kinds of weird things to happen (heard the starter turn over for about half a second WHILE THE KEYS WERE IN MY POCKET!!!). Luckily, I was able to seal the windshield myself and no longer have the leak/GEM issue. After that whole ordeal, I decided to put the power steering problems on the back burner until that NEEDED addressing.

Well here recently, my front-right wheel bearing was starting to go out so last week I decided to replace both front hub assemblies with new Timken units (including new ABS sensors). So I’m in my driveway, I have the front end sitting on jack stands so I can turn the wheel back and forth in order to reach the 4 nuts holding the hub assembly to the knuckle (one of the 4 nuts wasn’t there on one of the original hubs so that was fun to find locally). Well I guess while I was turning the wheel to get to those nuts, I must have turned the wheel too fast or hit the bump stop too hard, because when I got back out of the truck to torque the nuts, I noticed dirty power steering fluid (well ATF) dripping down on the axle……great……

I did a quick lookover to see if I could notice any major leak location and noticed that the cap to the power steering pump reservoir had popped open/off and was just sitting on the reservoir opening. It didn’t look like much fluid had been lost so I twisted the cap back on and finished the job since it was almost dark outside.

Well I buttoned everything up, cranked the truck up and drove it around the neighborhood to make sure everything felt tight. Once I got moving, I noticed the brake pedal felt soft and was giving off similar “vibration” or “groaning” sound as when the ABS engaged, and my steering felt very weak. This feeling/sound was constant the entire drive and I could even hear the sound when I wasn’t touching the brake. It was getting late at this point so I decided to just get back home and park it for the night.

The next day I checked the PS fluid level and noticed it wasn’t touching the dipstick on the cap so I topped it off with ATF and took it for a drive. After adding the fluid, the weird feeling in the brakes was gone but my steering was still very weak. Turning the steering wheel was much more difficult and the “wander” at higher speeds was also much worse.
So there’s the background. Up until this point, I had little-to-no knowledge on the power steering/brake system. After doing some research, I now have a general idea of how the brakes are pulling off of the power steering pump which is why I was having the brake issues.

From what I’ve researched, I believe my brakes are fine now that I’ve added the ATF to the power steering pump. Some verification of that would be great! I guess my question now is where to go from here in order to fix my weak power steering. I’m having a hard time trying to decide whether I’m having a power steering PUMP issue, or a steering gear issue…..or both….from what I’ve read, the “wander” I’m experiencing seems to be a common steering gear problem but the “weakness” I’m feeling seems to be a pump problem? Could a worn out steering gear cause the difficult steering that I am feeling? Seems to me that if my pump was going out, I’d be having the same “weak” feeling in my brakes as well, and that doesn’t seem to be the case; my brakes feel pretty solid, I don’t have any problem slowing down or stopping suddenly.

We just had our first child in October so time and money are not as available as they used to be, obviously, so I’m really here trying to get a good plan together before I carve out time to work on this. Does this sound like more of a pump issue than a steering gear issue? Does it sound like BOTH are having problems? Any sort of guidance on starting this adventure would be much appreciated!

Thanks

 

I think you need to seperate the issues.

first, what likely occurred was you got low on ATF in the steering pump reservoir, this cause foaming and it blew the cap off, when the foaming went down overnight is when you noticed the low lever.

not likely the that the pump or gear is the cause of your wander but rather your alignment.
we can addresses that separately after you give me some measurments, need you to measure from the center of your wheel hub straight up to the bottom of the fender arch at all 4 corners and post the info.

once you ran the pump with foam in it it got air through out the system and now likely needs a proper bleeding.
read how to change the fluid by flushing and then bleed the system in the tech folder.

Check to see if your steering gear is worn out, with the key on but not running look out the window at he front tire, now turn the wheel gentely, how far in either direction can you turn before the wheel just starts to move ?

 

I agree with all that pirate stated.

I would just add that with a 7.3 diesel the brakes and power steering are connected. The power steering pump powers the brakes via hydroboost. So a issue with one will affect the other.

Weak steering with hydroboost can be traced most of the time to ball joints. If they are old and stiff then they can over power the steering pump. If new and not installed properly they will again over power pump. Check torque needed to turn wheels and fix ball joints if torque spec is exceeded.

Wander is probably due to front springs sagging and/or alignment issues. Shims tend to fix most wandering issues.

Now, there are known issues with hydroboost hose restrictions on factory hydroboost hoses. Special kits are available to address these hoses. Some people have custom hydraulic hoses made so the restrictions are eliminated on the hydroboost hoses.

 

Well the previous owner has done the X-code springs in the front and the ball joints looked to be in good condition (I believe they were replaced with ones with a grease fitting but I'll have to double check). I cannot rule out a alignment, been a while since the last one. I'll have to get those measurements tomorrow when the weather clears up

 

Yes you need to make sure ball joints are not too tight and are in spec.

X codes add a few inches, so check to make sure track bar is not pulling front end to left too much. You may need an adjustable track bar.

 

Update: Been busy with work and the little one but i managed to get a chance to take the X to get an alignment. I asked if i could walk out into the shop to take a look under the truck while they had it in the air which they had no problem with. Me and the tech pushed and pulled on the tires checking for any kind of play - everything was nice and tight as it should be. Afterwards, me and the tech were talking about the results of the alignment and it looks like whoever owned it before me must have installed an alignment bushing on the passenger side (don't know why) so we couldn't get that side's camber within spec....another thing to address lol I do not believe this has anything to do with my weak steering which is mostly what i'm focused on.

I went ahead and bought a new power steering pump which should be here today or tomorrow, as well as new pressure hoses and reservoir cap. I feel certain the current pump is on its last leg either way, it takes two hands to turn the steering wheel at a stop but doesn't feel like it's fighting the ball joints or anything; just feels like i have no power steering. The only thing that makes me question the power steering pump NOT being the problem is that my brakes seem to be working just fine. Do the brakes need full pressure from the PS pump to function properly? Or will they work just fine with minimum pressure from the pump?

 

The power steering pumps suck on these trucks. If someone would patent a solid pump upgrade they would kill it.

 

I think the pumps are fine.
On hydroboost systems the main issue is trying to turn wheels while stopped with foot on brake pedal.

I think it's a flow issue, as you look at the end connector on line going to hydroboost from pump you will see that it's barely 1/4" inside diameter where the crimp is.

Custom lines with banjo fittings have fixed alot of this issue.

Big tires, lift kits, and stiff ball joints do not help either.

 

I am very interested in this larger hydroboost line.I read about it but no one gives up any details other than how restrictive the line is acting like an orifice. Can you share some information? I am yanking my engine right now and while it’s at the machine shop I’m installing a custom fuel system so I can do some hydroboost work as well. PM me if you don’t care to share on the forum but sharing with everyone would be cool too.

 

I'm interested in the hydroboost line upgrades as well if you wouldn't mind sharing

 

This should help you with this upgrade.