Qashquai Wheel Alignment

[Smitea]

To all Technical Forum Members

Note this post has been transferred from the "Off Topic" section after realising that there is a "Chassis, Wheels & Tyres Section on this Forum.

For clarity sake I repeat the history so far

After purchasing a new 2023 Nissan Qashqai Acenta Xtronic CVT, I noticed that the caster angles on both front wheels are not within the specified tolerances as per Nissan's Wheel Alignment Specifications. As these angles are fixed during the manufacturing process and not adjustable like camber and toe, I have contacted Nissan South Africa in this regard.
It was recommended that the vehicle is driven for 5 000 to 10 000Km in order for the suspension to settle.

Needless to say, I am not at all satisfied with this solution. I have never heard of "driving a car to get it into specification"

According to the Nissan factory specifications, caster angles should be between +7 degrees 25 minutes and + 5 degrees 55 minutes (ideal 6 degrees 40 minutes) however, the current readings are as follows:
Left front = + 5 degrees 23 minutes
Right front = + 5 degrees 25 minutes
The current caster angles are therefore less positive than the minimum tolerance of 5 degrees 55 minutes.

As it is well known that caster angles play a critical role in the steering geometry of a car, I have the following question:

Is this vehicle suitable to drive with respect to:
a) safety
b) road holding and stability
c) abnormal tyre and suspension wear
d) any other related matters affected by caster angles, not mentioned above

Your urgent response, opinion and advice will be highly appreciated.

Eben Smit

[lewisbryant]

Where are you retrieving your OEM specifications from? Nissan themselves? Or another company?

[Smitea]

Hi Lewisbryant

Thank you for your question.

The Nissan Dealer where the new vehicle was bought has it's own wheel alignment machine and made use of specifications provided by Nissan South Africa.

[lewisbryant]

According to the workshop manual for j12 2022 onwards
Front caster should be:

Minimum 4 degrees 45 minutes
Nominal 5 degrees 30 minutes
Maximum 6 degrees 15 minutes

[Aspire23]

Are these dimensions to be calibrated with any load in the vehicle? Totally agree driving to get within spec is pointless and only achievable if you hit deep potholes, ruts and humps. Potentially, do the dealers technicians know how to use their wheel alignment equipment? From my experience usually the answer is not very well. Was the steering held firmly in the straight ahead position. Were the tyre pressures set correctly. Were any loads in the boot taken out/into consideration. Were the top suspensions mount checked for correct strut to top hat fixing. Any tyre wear issues noted. Were the alignment gauges fitted to the vehicle correctly. Many variables but if the front tracking is out all other readings can be affected.

[roadster]

As I said in your first post the manufacturer I worked for ( in the UK) specified this geometry in a loaded condition which will change ( usually increase) the caster angle because the lower wishbone usually pivots to move the lower ball joint perpendicularly. In any case other joints such as roll bar or tie bar generally have flexible bushes. If you want to pursue this further I suggest repeating the measurements with a different load for example with four passengers. Suspension does also tend to settle after a car has clocked up some miles so its not unreasonable to suggest that the relatively insignificant 1/2 a degree error will disappear.

Regarding tyre wear it has to be accepted that modern suspension is a compromise on cost and comfort rather than the perfect geometry you would expect in a racing car. It also has to be satisfactory over a wide range of load conditions and accommodate different wheel and tyre sizes over a range of variants. When you add variations of driving styles and speeds it is unusual to find tyres which wear in a perfectly even way and this is why most manufacturers still recommend diagonal wheel changes.