Suspension arms and rear axle are attached to a box-shaped cross member, which is attached to the underbody through rubber pads.
Characteristics of rear suspension springs
From model year 1977 on BMW «525», «528» And «528i» suspensions with the following characteristics were installed.
Free length, mm: 343.
Marking: one orange + one red mark, green mark or no mark.
Spring force, kgf:
- with a red mark: 376-385;
- unmarked: 386-404;
- with a green label: 395-404.
Number of coils of spring: 9.
Number of working turns: 7.5.
From model year 1980 on all models, the rear suspension springs either have the same red color mark or no mark.
Diameter of the stabilizer bar («520i» And «528»), mm: 16.
Shock absorbers
Double-acting hydraulic telescopic shock absorbers.
Shock absorber characteristics
On some vehicles with reinforced suspension, Bilstein brand shock absorbers with different characteristics were installed instead of Water shock absorbers.
From model year 1977 on BMW «525», «528» And «528i» shock absorbers of the Vode brand were installed with the following characteristics, length «IN» which is 524.4 mm, length «WITH» - 338.3 mm.
Rear wheel alignment
For a vehicle with a full fuel tank under load, which is distributed at 68 kgf in the front seats plus 68 kgf in the rear seat plus 25 kgf in the left side of the luggage compartment, the rear wheel alignment must be as follows: (for reference):
- convergence: 0°10'±10 or 1 mm;
- negative camber: -2°±30'.
From model year 1978 rear wheel alignment for BMW «525», «528», «528i» is 0°19'±7' or 2±0.8 mm.
Rear wheel hubs
The splined rear wheel drive shaft rotates inside the suspension arm in two ball bearings.
The axial clearance of the bearings is determined by the distance sleeve and adjusting rings with a thickness of 4.80 to 5.25 mm with an interval of 0.10 mm.
Bearing brands:
- internal: 6206 SZ DIN 625;
- outdoor: 6208 SZ DIN 625.
Axial clearance of bearings, mm: 0.05-0.06 (from MY 1978: 0.05-0.10).
Lubrication quantity (Shell Darina 2 type), laid in bearings, g: 35.
Tightening torques of the main threaded connections, kgf·m
- Nut of a bolt of fastening of the suspension arm to a crossbar of a back suspension bracket: 6,7-7,5*.
- Nut of a bolt of fastening of the shock-absorber to the suspension arm: 12,0-13,0.
- Upper support nut: 2.5-2.8.
- Wheel nut: 8.0-9.0.
* For vehicle under load (see above).