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Unread 01-24-2014, 04:02 PM   #1
RoldGold
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1996 ZJ 
 
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Location: Philadelphia, PA
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Why is speed proportional steering a bad thing

Over the past couple weeks I've noticed quite a few forum posts that say to avoid the 96 PS pumps that have the proportional steering. I've got it, and this being my first car, I don't know what's bad about it. Why should I avoid it/should've avoided it?

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Unread 01-24-2014, 05:01 PM   #2
shaban
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Nothing's wrong with it. Speed proportional steering uses a different spool valve in the steering box and a different pump, so they are not not interchangeable with regular pumps/boxes, only as a set.

So if you've got a speed proportional steering, you can only swap in SP pump and SP steering box.
If you've got a regular steering, you can only swap in regular pump and regular box.

I've put a non-SP box from an XJ into my ZJ when mine blew (it was a SP box) and it worked fine, however there's something in the FSM that says "steering response may be affected if doing so".
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Unread 01-24-2014, 06:20 PM   #3
KJK
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The "bad" part is the components are more expensive when it comes time to replace them. Other than that, it's fine.
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Unread 01-24-2014, 06:36 PM   #4
Purcell69
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When combined with a five speed MT, it can be annoying. There is nothing worse than turning to pull in to a parking space in a crowded lot, pushing in the clutch to coast in and having the engine drop to idle and at the same time, the PS feels like a manual steering box all of the sudden. Usually I "blip" the throttle while holding the clutch. After 21 years with this Jeep, I am used to it, but it still surprises me from time to time.

-Joe
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Unread 01-24-2014, 11:24 PM   #5
KJK
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Quote:
Originally Posted by Purcell69
When combined with a five speed MT, it can be annoying. There is nothing worse than turning to pull in to a parking space in a crowded lot, pushing in the clutch to coast in and having the engine drop to idle and at the same time, the PS feels like a manual steering box all of the sudden. Usually I "blip" the throttle while holding the clutch. After 21 years with this Jeep, I am used to it, but it still surprises me from time to time. -Joe
It should have the most assist at idle and less as the rpm increases.
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Unread 01-25-2014, 01:32 AM   #6
5-90
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I don't like it because I expect consistent behaviour from my vehicle's systems, I don't like it when they change for whatever reason.

I don't like ABS for the same reason - and it gets all screwy when I "feather" the brakes to slow down, as I was trained to do.

I definitely don't like any system that I can function without, don't want to pay for, but am forced to have anyhow (ABS, for starters.) I don't like "safety devices" that allow a driver to abdicate responsibility - since I was trained to take responsibility for anything that happens as a result of my maintenance or operation of a vehicle. I don't like the trend toward "smart" cars that allow stupid drivers.

"Feature creep" in creature features is bad enough - but when it's mandated as a "safety push," I draw the line. Your #1 safety device is that mushy 1800cc or so between your ears - if you can't use that properly, then nothing else will be of any help to you (if you can use it properly, you don't need anything else.)
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Unread 01-25-2014, 09:58 AM   #7
Technohead
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Exactly, the more complicated it is the more that can go wrong.
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Unread 01-25-2014, 10:15 AM   #8
dusterdude
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Not sure about stupid drivers,but lazy sure fits the bill
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Unread 01-25-2014, 02:53 PM   #9
Purcell69
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Quote:
Originally Posted by KJK View Post
It should have the most assist at idle and less as the rpm increases.
That's funny. At idle the PS has a 50/50 chance at being normal or sluggish and has always been that way since day 1 (new). Above idle, the PS feels normal. I just figured it was proportional steering, as was told by the dealer about 20 years ago. It's been annoying, but if it ain't broke....

Now you've given me a reason to try and fix it. Damn.

-Joe
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Unread 01-25-2014, 04:13 PM   #10
shaban
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As far as I know, PS just reduces the amount of assist at 40+ speeds, full assist at idle or slow speeds.
Mine's working fine at idle by the way, and I've got a speed proportional.
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