Many customers fall into the 'bigger is better' trap and shop only for the largest sway bar they can find. Sometimes this works, but many times they are compromising their vehicle's performance. If other modifications have been made - increased spring rate, lowered height, change in roll center, etc. - the best sway bar may be smaller. The vehicle is a combination of its parts and it doesn't care how massive and cool the bar may look, it only cares how the sway bar interacts with the rest of its components. This is why Hellwig produces adjustable sway bars for many applications. The adjustable sway bar allows you to tune the vehicle to your driving style and suspension components. Hellwig also manufacture more than one diameter for popular applications to allow the customer to match the right sway bar to the vehicle.
The poly block in the Pro Series is primarily to place tension between the Hellwig Pro Series and the vehicles main leaf. This accomplishes two things. One, it keeps the u-bolt and cross bar assembly tight on severe rebound to prevent noise (rattling) from lack of tension on the u-bolt. And second, it actually acts as a spring stabilizer to resist body roll in corners or high wind.
Hellwig can not change the GVWR of any vehicle with the addition of a helper spring or air kit. Brakes, tires, wheels and axle ratings along with many other factors determine any particular vehicles GVWR.
The Load Pro Series, LP 25 and LP 35s have mounting hardware sold separately. The Pro Series, LP 15, EZ 990, EZ 1000, EZ 550 include all mounting hardware.
All Hellwig Helper Springs are sold in sets, to take care of both the driver and the passenger side of the vehicle.
With only a few exceptions all Hellwig sway bar kits come with bushings. Kits that do not have bushings are designed to mount without them.