possibly with the seals swelled, there is less give in the rack, so the tie rod ends move around less, and your steering stays on track.

an analogy would be that having a solid bar in place of the rack would result in absolutely no variance in the steering direction, leading to absolutely straight tracking.

++

 

That's what I was thinking but given the forces and and dynamic actions involved I'm not sure I can quite beleive it. I've not heard anyone else mention this issue. Now it also maybe be a combination of the alignment settings and this issue. It definitely changed for the better.

But if it's true I wonder what the real problems with these racks are? This adding of a "conditioner" fluid sounds an awful lot like a $9 band aide.

 

So the PAS fluid fixed your problem? I added PAS fluid before my juddering started. Then my noise went away, then came back. Then I added Lucas Oil Stop Leak Power Steering treatment which made the noise go away. Then my judder started shortly thereafter! What gives!

Can I add PAS fluid again?

 

You appear to have a different set of issues. I don't think they've been seen on here before.

If you have an XJ8 that probably explains it - and you'd be better in the right forum

 

I think I'd stop trying too many solutions simultaneously. Maybe go back to square one and have a dealer flush refill the fluid and look into the TSBs specific to the issue and your model of car. I have no Idea what that combination of additives might be doing.

I don't even understand what's going on with mine except that two issues got better and the squeak is greatly reduced but as yet it is not gone @ 400 miles .

 

Think of it as a combination of steering rack, and a steering damper.

Dynamics yes, but anything that cuts down on random movements is bound to help tracking.

You can move a lot of fluid from one chamber to another through seepage if enough time passes. For example, if one side is toed a bit more, and wants to straigten out, the force is constant as long as the wheel is rolling.

 

Supposedly the additive is for a seal (or seals) and that doesn't strike me as at all impossible, chemically speaking. Plus, it seems to work (for most cars). If the seal then works as designed and allows the rack to work as designed, isn't that it?

Any remaining noise might be one of the other - much rarer - noises, such as the bush which I somewhat dimly recall reading is lowish on the stering column (i.e. for once the noise actually IS in the cabin).

 

I find it very hard to believe that if it's the seal on the steering column end of the rack then this is causing the noise and also causing my bad chassis tracking performance. That's a hell of a lot of dampening effect being exerted by the lip of a seal on a shaft that's maybe .75" or so in diameter.

Perhaps what's happening inside of that rack with the squeak is a bit more complicated than this? Someone in the Jaguar engineering department must have a more detailed description than - just add this stuff.

 

I don't know which seal(s). My guess would be something internal but I don't know (or, really, care LOL).

Yes jag (or ZF whose rack it is) will know but why would they say? If you really care, ask jag (not a dealer) and hope for an answer

I was referring also to a separate issue which can occur with a bush making a noise, in case that's also affecting someone.

 

The way I was interpreting the situation is that the rack was actually acting as more of a dampener because of something being tighter than intended hence the squeek. So, the car would be more likely to follow road irregularities. But honestly I'm mystified at this point.

 

are you sure the noise in comming from the rack? mine had the same noise I added the additive and it did not help much. The noise was in the wheel. Since I was replacing the steering wheel anyways I took the wheel off and checked everything out. When I put the new wheel on I made sure everything was aligned up right and the noise went away.

I think 95% of time the additive works the other 5% the noise is in the steering wheel. It's work a shot since it only take 1o mins to pull the wheel.

 

The dealer may get a second shot soon. I'm going on a long trip in 10 days and if it still squeaks after that I'll take it back in.

In the mean time I need to have the alignment re-checked so I have to dig up that long thread again and see if I'm currently too far a field of what Brutal was suggesting.

 

I posted earlier in this thread...

going to use a turkey baster to remove the fluid in my reservoir and add the additive and new fluid on friday.

I will let you guys know how i make out as well!!

 

I did this before every drive, and the last two times I did this, the judder was cured! I think I will go ahead and keep changing out the fluid until I'm out (I started with 2 fresh quarts of fluid).

 

Would it be for the same year? I found one on ebay for an '03 LS but it says it'll only fit on '00 s-types (not an '03 like mine). Considering it's half the price and I need one, I'd appreciate anyone who could confirm exactly which one I would need.

 

2003-2006 Lincoln Jaguar Power Steering Rack and Pinion | eBay

 

Not the $150 price I hoped for like some other Lincolns I saw. I guess $300 is as good as I'll find.

 

Turns out it's not fixed, but it's much better than before, I will keep flushing.

 

yeah not as good as the 150 but 300 for one with a lifetime warranty to me is a steal. From what I have seen they are pretty cake to install as well.

 

I pulled all the fluid out of the reservoir and added the power steering additive from jaguar today. Performed the lock to lock wheel rotations and drive in circles exactly as the TSB calls for and the noise has seemed to subside a tad but the shutter is actually worse!!!

Hopefully the additive continues to make its way thru the system as i drive it over the next couple of days. Other than the usage as the TSB calls for ive only put about 10 miles on the car. Im going to check the fluid level in the morning as it is dark out now, but it should be just fine. I returned the level right to the max fill line on the reservoir.

Ill post back in a few days after i put some mileage on the car with the additive and fresh fluid and let you guys know how i make out!