Tom in Austin

Recently Sean replaced the leaky steering rack in my car (afaik, the original one). He and Roger went to some considerable lengths to try to locate a true MY 90+ rebuilt rack, but as I expected no one really differentiates these from the outwardly-identical S4 type.

The question was whether going with an S4 rack would make any change in the steering effort & feel since a different spool valve was used starting in 90.

Well, after several weeks of driving, I can honestly say I haven't felt any difference at all. The MY 90 change actually had three parts ... a higher pressure pump, a different restrictor in the high-pressure line and the spool valve in the rack. So with the first two still in place, it appears they must have made most of the difference rather than the rack.

Just a little trivia for anyone who's ever wondered about changing the rack on their 90+ car.

Mark Anderson

Good data point but I think Nicole had a different experience. I wonder why

Bilal928S4

When I replaced my steering rack on my 90 S4, I got one from Mark and it worked fine. I did not know that there was a difference in the racks.

GregBBRD

I've had customers that noticed a huge difference. However, the wider and stickier the tires are, the less noticeable the difference. I've had such huge problems with clocking and steering effort, that I now rebuild all the "low effort" racks, in house....personally doing this.

I believe that most of the rebuilders have no clue about which rack is which, or what is the difference. Hell, if you are taking the rack apart (and re-assembling) with a punch and a hammer....how good could you possibly be?

Could I borrow your axe? I'm going to work on my Porsche.....

Since the "lower effort" parts are circulating around, pure random chance would say that some people are going to get racks with the lower effort and not know they were getting them.

Who knows what they really get, in exchange?

Bill Ball

We had a contrary experience with Nicole's 91. A common rebuilt replacement rack increased the steering effort, primarily in slow parking maneuvers. Nicole managed to locate a true MY91+ rack, I think directly from ZF, although the documentation regarding the source has been lost. After installing that, lower steering effort in slow maneuvers was restored. Personally, I don't think this is enough of an issue to try to hunt down the elusive and some say non-existent MY91+ rack. People who usually drive American cars do comment on how much steering effort is required when driving my 89, again, particularly in slow maneuvers. When pointed out, I do notice it. Maybe there's more effort at speed as well, but I'm OK with it. Nicole was not. The Service Tech Info book for 91 mentions the higher pressure pump, but as to the rack itself it only calls out new "friction optimized seals", whatever those are, but does not mention a different spool valve.

It's good to see Greg is on top of this and can rebuild MY91+ racks correctly.

Bill Ball

There is no difference. The new rack started in MY91.

Randy V

Huge improvement when GB got me a GTS rack that he rebuilt .

Seems the PO had a rebuilt S4 rack installed at some point.

LarryM

I noticed a difference when I replaced the one on my 95. The replacement had more effort than the stock one. It had a bad leak. Also the replacement had the U joint 180 off. That was a fun fix.

I kept my original one hoping that I could have it rebuilt or fix it myself. Is there a service that mine can be rebuilt and have it returned? Sounds like there are a few expensive tools to do it right yourself.

LM

BC

Greg - do you get your seals from Transgo?

GregBBRD

I hand rebuild 928 steering racks, on an individual basis.....no exchange. I don't take them apart and put them back together with a hammer and a punch. As a matter of fact, I will not re-rebuild any rack that has been "attacked" like this....it is terrible workmanship and ruins the rack, as far as I'm concerned.

They come back "clocked" exactly like the way they arrive here. The racks cost $695 for me to rebuild....which is significantly less than the "rebuilt exchanges" that other venders offer.

"When they compete with my quality, I will compete with their price"....there is a difference from one mechanic/rebuilder of pieces to another mechanic/rebuilder of pieces.

Nicole

Bill and I first installed a ZF rebuilt rack, which had two issues:

a. The steering wheel was not centered when the rack was centered
b. The steering effort was significantly higher than before the replacement

Susan from DEVEK got me a later style rack through Porsche, which

a. centered properly
b. restored the higher level power assist I was used to (and which was a big reason why I chose to own a 91 model 928)

I wonder, how many of the 91 and later models still have the proper steering rack. My guess is that most of the racks that have been replaced in these later models are not the correct ones.

Nicole

Some day, your orignal rack will be worth its weight in gold...

Is it possible for someone who has the wrong type to have you convert it to the later style rack?

GregBBRD

Yes, amazingly simple to do.

I'm working on having the necessary pieces made....they will be made, right after the torque tube shafts I'm working on.

Not only that, but I will be making pieces that increase the amount of assist even more.....for people that have installed wider tires and wheels.

The pieces required are really simple. The "safety part" of it is what is difficult to engineer and then test....it steers the car.

SeanR

Just so it is known, we saved the rack from Toms car just in case he was not happy with the rebuild. Guess where it is right now Rebuilt and in stock. Damn core charges suck so I'm glad another was on hand to be sent in. I'm going to start collecting these things like I do some of the other bits.

GregBBRD

BTW....Just before I bit the bullet and started rebuilding these, myself (I really don't want to rebuild everything....I do it only out of necessity), I got so tired of taking generic rebuilds apart and re-clocking them, I ordered a rebuilt GTS rack, from Porsche. Rebuilt by ZF and not clocked correctly.....

I really believe that the little "details" about the 928's are slowly getting "lost".....and in another 10 years....all the rebuilt racks will be exactly the same part number.....and luck will determine if you have one that steers easy or hard.