Notices
Wheels & Tires 350Z Rollers and Rubbers

Steering

Thread Tools
 
Search this Thread
 
Old May 7, 2011 | 04:59 PM
  #1  
Loomis's Avatar
Loomis
Thread Starter
Registered User
 
Joined: Mar 2011
Posts: 17
Likes: 0
From: Western Kentucky
Default Steering

What is the purpose of the speed sensitive steering? I test drove a 03 today with 50,000 mi.. It was very hard to steer at low (parking lot) speeds. It had new front tires but not rears. Seemed to drift to the right at highway speeds also. I'm concerned the alignment might be off and they replaced the tires to cover the tracks. What actually controls the steering? Could something be screwed up in the computer to cause this? Other than that the cat is in great shape.
Reply
Old May 7, 2011 | 05:05 PM
  #2  
NISMO_558's Avatar
NISMO_558
Registered User
iTrader: (1)
 
Joined: Dec 2006
Posts: 4,003
Likes: 4
From: Minnesota
Default

Originally Posted by Loomis
What is the purpose of the speed sensitive steering? I test drove a 03 today with 50,000 mi.. It was very hard to steer at low (parking lot) speeds. It had new front tires but not rears. Seemed to drift to the right at highway speeds also. I'm concerned the alignment might be off and they replaced the tires to cover the tracks. What actually controls the steering? Could something be screwed up in the computer to cause this? Other than that the cat is in great shape.
Um, the steering wheel and the driver
Reply
Old May 7, 2011 | 05:31 PM
  #3  
Loomis's Avatar
Loomis
Thread Starter
Registered User
 
Joined: Mar 2011
Posts: 17
Likes: 0
From: Western Kentucky
Default

Um, I believe if you were to check, the driver's brain controls his (her) appendages which in turn contol the steering wheel which in turn controls the steering shaft which in turn controls the hydraulic valve in the steering unit while at the same time controlling the pinion gear which in turn controls the rack gear which in turn controls the inner tie rod end which in turn controls the outer tie rod end via a connecting shaft. The outer tie rod end in turn controls the steering knuckle/spindle assembly which in turn controls the wheel/ tire combination. Perhaps my query wasn't stated clearly enough for some of the more seasoned mechanics on this blog. What I was wondering about was the term "speed sensitive". Is there some other device thrown into the mix of items I have listed to make this mechanism more "sensitive" to driver input at certain speeds than at other speeds? Or is this just another standard "rat and pigeon" steeriing system with some fancy name to increase sales?
Reply
Old May 7, 2011 | 05:48 PM
  #4  
NISMO_558's Avatar
NISMO_558
Registered User
iTrader: (1)
 
Joined: Dec 2006
Posts: 4,003
Likes: 4
From: Minnesota
Default

Speed Sensitive Steering

An outgrowth of power steering is speed sensitive steering, where the steering is heavily assisted at low speed and lightly assisted at high speed. The auto makers perceive that motorists might need to make large steering inputs while manoeuvering for parking, but not while traveling at high speed. The first vehicle with this feature was the Citroën SM with its Diravi layout[citation needed], although rather than altering the amount of assistance as in modern power steering systems, it altered the pressure on a centring cam which made the steering wheel try to "spring" back to the straight-ahead position. Modern speed-sensitive power steering systems reduce the mechanical or electrical assistance as the vehicle speed increases, giving a more direct feel. This feature is gradually becoming more common.
Reply
Old May 7, 2011 | 06:02 PM
  #5  
Loomis's Avatar
Loomis
Thread Starter
Registered User
 
Joined: Mar 2011
Posts: 17
Likes: 0
From: Western Kentucky
Default

Thank you NISMO for an intelligent answer. I noticed the steering wheel really tried to re-center it's position a lower speeds. None of the others (newer models) I have driven were this noticeable. Is this a quirk of the 03 model since it was the first year, or could there be a problem?
Reply
Old May 7, 2011 | 06:09 PM
  #6  
Loomis's Avatar
Loomis
Thread Starter
Registered User
 
Joined: Mar 2011
Posts: 17
Likes: 0
From: Western Kentucky
Default

A note. I just noticed on the specifications for different models of 350Z
that the steering on the 03,04, & 05 models is refered to as" Engine speed sensitive rack and pinion", while the 06 and up is referred to as "vehicle speed sensitive". I've driven 05 and 06 models and they did not have such heavy steering at low speeds. ???
Reply
Old May 8, 2011 | 09:40 AM
  #7  
harman850t5's Avatar
harman850t5
Registered User
iTrader: (8)
 
Joined: Dec 2010
Posts: 290
Likes: 1
From: Central PA
Default

i have an 03, the steering is a little heavy at lower speeds, but I don't think it's really a problem. You could always try a power steering flush or get it checked into by a mechanic if you think there is an issue.
Reply
Old May 8, 2011 | 11:48 AM
  #8  
terrasmak's Avatar
terrasmak
Super Moderator
MY350Z.COM
Premier Member
15 Year Member
Liked
Loved
Community Favorite
iTrader: (8)
 
Joined: Jan 2007
Posts: 29,114
Likes: 2,394
From: Sin City
Default

As the front end bushings wear out the low speed steering gets harder and harder.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
aarrgghh
Forced Induction
15
May 1, 2022 11:04 AM
HoBrahYouStink
Media Share
32
Jun 24, 2016 10:58 PM
Depravity
Brakes & Suspension
14
Oct 1, 2015 04:49 PM
dragon11689
Brakes & Suspension
2
Sep 7, 2015 02:47 PM




All times are GMT -8. The time now is 05:01 PM.