Quick Information About Bilstein Collar Struts
Cars have been using struts for a lot of years, but trucks are starting to use them as well. Many truck owners we talk to are not familiar with strut suspensions. Here below are two examples just to give you a closer idea of what they are.
Both units use a loose spring seat. In some cases you will use the original equipment spring seat, but in these examples, you get new ones. The one on the left is machined from aluminum, the right one is a stamped steel spring seat.
Notice how the spring seats are installed, like a hat. On the aluminum one, if you were to look inside the bottom, you can see where it is machined to sit on the snap-ring. Like this:
Here below is a close up of the body on a Bilstein 5100 racing unit. This one allows you to alter the height of the vehicle. (this is not applicable to shock absorbers, only struts). By relocating the C-clip into different grooves, this moves the spring seat up on the body of the strut. Which in turn, moves the coil spring up.
Moving the coil-spring upwards moves the body of the vehicle up, thus raising it higher than stock. Simple but very effective.
Here below is a close up of the body on a regular Bilstein (Heavy-Duty or Sport) unit. Notice there is only one groove, to install the spring perch into the stock location only.
Common Questions about these type units:
1. Do the springs need to be removed?:
Yes. Normally a spring compressor tool will be needed, since the spring, boot, bump stop, and or mount may need to be removed off the old unit and installed on the new unit.
2. How sturdy is that snap ring?
Machining a groove and using a snap-ring for the spring seat has been used on performance and racing cars for decades.
3. The 5100 Racing units are better than the Heavy Duty's?
Not exactly. The 5100s have a valving for racing and off-road performance, while the Heavy Duty units have a valving more for street, everyday driving. The 5100s commonly allow for alternative height choices as well. Heavy Duty units are painted, 5100's are not. Both units have the same high quality parts and machining inside and out. So, which one is better depends on your needs and the kind of driving or modifications you plan on doing.