1977 XJ6-C. I need to rebuild or replace my steering rack. I believe I read here that the hot setup is to replace my current rack with a remanufactured one from a Series 3 XJ6. Is this good information? What years might be best? Do I worry about tall or short tower? Will I be able to use my current hoses? Then I read this: The long tower were used in Series 1 & 2 cars with 6cyl. The Series 3 XJ, all V12's XJ and XJ-S always got short tower rack. The Series 3 does have a slightly quicker ratio. The hot setup is the ZF rack found in the 1992 and later XJ-S and Aston Martin DB7. This rack offers better feel, smoother operation and better seals and improved mounting. It's also aluminium and much lighter than the earlier racks. I did the upgrade and the difference is slight but noticeable. The ZF rack is a bolt in upgrade. The fluid lines are in a slightly different location but the same hoses and fitting can still be used. So; should I start looking for a 92 rack??

Thanks all
geneo

 

I don't know about any of the others you mention, but I can tell you from my own experience, I wish I had rebuilt my S2 rack instead of installing the S3 rack.

They talk about "better feel" This is subjective. My old Series 2 high tower OEM rack gave me One Finger Steering such as I have in my work truck. I found it smooth and as responsive as I needed it to be. It would still be in the car except I was told by those in a position to know, that no one rebuilds high tower racks anymore, and mine seriously needed it. If I had known at the time what I know now I would have attempted rebuilding it myself.

The replacement S3 short tower rack is Much harder to operate. GONE is my beloved One Finger Steering. In fact, I have to wear driving gloves to have the same confidence driving the car in town; there's that much difference in "feel." To say I was disappointed is a Massive Understatement! But there's no going back now.

I'm not even going to get into the modifications required to mount it in the car, some of which were considerable. I wrote up a post about that adventure, I'll see if I can find it for you.

EDIT: https://www.jaguarforums.com/forum/x...0/#post1226209
/EDIT
(';')

 

The Later ZF racks are great and are less prone to leaks. Almost a bolt in. The pressure side needs to be tweaked a bit for the hose to line up properly. Quite easy on a Inline 6 but on a V12 I'd source a later power steering pressure hose and and then adapt the pump side. ZF did an amazing job reverse engineering the Adwest Powr-rack. The feel is nearly the same just more precise, especially on center.

I've had the good fortune to experience many racks over the years, and the ones that have had no work done always feel more natural. For example, I recently put a rebuilt rack into an XJS and it feels OK but not as good as an original un-rebuilt unit. Perhaps with some miles it will brake in. I also have cars with virgin racks... one from a DB7 with under 6k and one from an late XJS with 40k. Both were never apart and feel more much natural.

I'd take a chance on a 2 or 3 salvages racks and hope for the best before having a rebuilt. Later racks seldom fail unless abused so chances are favorable.

As far as ratio's go, I believe the early Series 1 & 2 "school bus" tall racks were 3.0 turns lock to lock, the later XJS/Series 3 racks were 2.7 turns lock to lock and the DB7 / XJS sport pack racks were 2.5 turns lock to lock.

The 2.7 XJS ZF rack is the one to have for Day to Day driving. The DB7 and XJS sport pack 2.5 rack are somewhat notchy on center becasue the rack, pinion and body are somewhat small to be precise at the 2.5 ratio.

LnrB, there is probably something wrong with that rebuilt S3 rack or the pressure hose has a restriction. S3 racks were just as over boosted as Series 2 racks. Ive experienced many rebuilt racks over the years and they never feel original and each one differs. One of them leaked right out of the box. Ive also seen it where some one has the pressure hose made or repaired and the chap at the hydrolic shop over crimped the hose so much it crushed the tube to the point where flow became restricted. Pressure side flow restrictions will offer up a dull and heavy feel.

 

I think I wrote that. Anyway...if you go with a short tower rack you will need the longer intermediate shaft from a Series 3 XJ or any XJS. When I converted a series 2 I was able to bend the pressure hose to fit a Series 2 by hand. I made no other modification besides the longer intermediate shaft when fitting the later ZF rack.

If you do source a late rack don't try to change the bushings, unless you have a proper press. It will be extremely difficult to change the bushings otherwise. Early racks are much easier. If the bushings are in good shape you can tighten up the rack feel by cutting up eurathane washers and using the outer edge as a more solid spacer to keep the rack from moving side to side, If properly trimmed, the eurthane bush will fit over the existing bushing making this upgrade quite easy.

 

And that, Folks, is what is great about the Forum. True experts willing to share their knowledge.

Don't know if this helps but I have two series IIIs. My 79 which has a SBC and steers like Eleanor said - handles like a sports car and steers with one finger. The other one is an 87 and it's steering is much heavier - more like a modern car.

Jeff

 

I replaced the rack in my '84 because it was leaking, got it from a company in Atlanta back in 1995 or 96. The first replacement was a leaker too.

I called them and they sent another one which is still dry today, BUT, just like Elinor and icsamerica say, it is a harder rack to steer particularly at
slow speed.

However, I do not recall the old one ever being one-finger easy. Maybe the Series 3 racks are just harder for more "feedback"?
Also I replaced the original school bus steering wheel with a smaller 15", I replaced the tires with fat ones, and I replaced the rubber rack bushings with polyurethane, so I don't know if it is a result of the smaller steering wheel, fat tires, and poly bushes.

 

I question as to whether the "touch" issue is in the rack or the PS pump and the valves. AKA boost PSI's. Andrew Weinberg's Jaguar=Specialties addresses this,

My Lump uses a later version of the GM Saginaw pump and the original Jaguar SIII rack. Perhaps not quite finger steer, but close. Little effort needed even at almost no forward or rear motion. In my "Three bears logic", Just right.

Carl

 

When I converted a series 2 I was able to bend the pressure hose to fit a Series 2 by hand.

From my experience, the tall tower racks had the hoses wrap around the tower and come in from the rear, whereas the short tower hoses went in straight from the front. For this reason, I used the S3 hoses. Are you saying that it's possible to bend the metal ends of the hoses to work?

I definately prefer the S3 rack for its quicker ratio. My S1 with huge wheel and slow rack was cumbersome. With a S3 rack, smaller steering wheel, and new rack mounts and it felt great.

That's interesting about the later ZF rack; I'd never heard of that swap.

Rob

 

Sorry, the first line of the above post was a quote from icsamerica.

Rob

 

Here is ZF rack swap I did on a 77 coupe a few years back.