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With over 30yrs experience within the realm of chassis calibration and Pro-Drive accreditation i feel qualified to offer a voice on this habitual problem some MB's have.
The pull left is "NOT" a design feature intended to save the driver from hitting the barrier in the event he falls asleep. Personally i would prefer to hit the barrier on the right than the tree on the left.
So what's the problem?
The MB has a unique chassis calibration that performs in a executive level as well as a performance level. This remarkable tuning enables the cars to perform beyond expectation but there is a flaw, not in the car but in it's environment namely the road crown.
Some rules
If you have a pull you need to remove any mechanical defects, shocks, coils (front and rear) bushings an so on.
Tyres
The most common reason for a pull is the tyres, this i can explain why in another thread maybe but for now a simple test to see if the reason is the tyres is to move the fronts side-to-side, if the pull stops or changes direction then you have your criminal.
The chassis
The MB chassis is adjustable, the reason for this is over time MB knew the positions would move so we have the opportunity to correct the angles by either adjusting the pre-installed cams or fitting MB adjuster bolts.
The problem
Assuming all the above parameters have been met but the car is still pulling then the chassis needs to be calibrated. The problem is not the actual angles, it's the difference between them? Each angle offers particular forces and it's these forces we need to use to belay the pull.
The forces
Camber: This angle is conically compressive, deforming the tyres sidewall encouraging the tyre to roll into the cars centre. note this angle has many other duties but the conical effect is the one we are interested in now.
Castor: This angle offers directional stability, steering feel, weight and return. note this angle has many other duties but directional stability is the one we are interested in now.
Solution
Having met all the mechanical, pneumatic requirements now is the time to addresses the chassis positions.
Taken from a "non-distressed" chassis the procedure would be.
Camber
NSF: Increase: not recommended
OSF: Decrease: recommended
Castor
NSF: Increase: not recommended
OSF: Decrease: recommended.
I hope this thread adds some insight to this problem for members.
Regards
Tony@ wim
The pull left is "NOT" a design feature intended to save the driver from hitting the barrier in the event he falls asleep. Personally i would prefer to hit the barrier on the right than the tree on the left.
So what's the problem?
The MB has a unique chassis calibration that performs in a executive level as well as a performance level. This remarkable tuning enables the cars to perform beyond expectation but there is a flaw, not in the car but in it's environment namely the road crown.
Some rules
If you have a pull you need to remove any mechanical defects, shocks, coils (front and rear) bushings an so on.
Tyres
The most common reason for a pull is the tyres, this i can explain why in another thread maybe but for now a simple test to see if the reason is the tyres is to move the fronts side-to-side, if the pull stops or changes direction then you have your criminal.
The chassis
The MB chassis is adjustable, the reason for this is over time MB knew the positions would move so we have the opportunity to correct the angles by either adjusting the pre-installed cams or fitting MB adjuster bolts.
The problem
Assuming all the above parameters have been met but the car is still pulling then the chassis needs to be calibrated. The problem is not the actual angles, it's the difference between them? Each angle offers particular forces and it's these forces we need to use to belay the pull.
The forces
Camber: This angle is conically compressive, deforming the tyres sidewall encouraging the tyre to roll into the cars centre. note this angle has many other duties but the conical effect is the one we are interested in now.
Castor: This angle offers directional stability, steering feel, weight and return. note this angle has many other duties but directional stability is the one we are interested in now.
Solution
Having met all the mechanical, pneumatic requirements now is the time to addresses the chassis positions.
Taken from a "non-distressed" chassis the procedure would be.
Camber
NSF: Increase: not recommended
OSF: Decrease: recommended
Castor
NSF: Increase: not recommended
OSF: Decrease: recommended.
I hope this thread adds some insight to this problem for members.
Regards
Tony@ wim