4 Wheel & Off Road - - CONTENTS - John Cappa BY ED­I­[email protected] PHO­TOG­RA­PHY JOHN CAPPA

Level stance, more wheel travel, and bet­ter shock damp­ing for 2011-up GM 2500 and 3500 trucks.

ONE OF THE BIG­GEST AD­VAN­tages that the GM 2500 and 3500 HD trucks have over the other heavy-duty trucks in the cat­e­gory is the smoother and more pre­cise-han­dling in­de­pen­dent front sus­pen­sion. Of course, the solid front axle found on the Ford and Ram coun­ter­parts is a more bombproof de­sign, but if you’re look­ing for a good ride over a rough sur­face on a dai­ly­driven 4x4, then IFS is usu­ally the way to go. Un­for­tu­nately, mod­i­fy­ing an IFS sus­pen­sion for big­ger tires is quite a bit more com­pli­cated than lift­ing a solid-axle 4x4.

With all of this knowl­edge in hand, JD Fabri­ca­tion set out to level the stance of the 2011 to cur­rent GM HD trucks while im­prov-

ing the ride with 2 inches more wheel travel up front and tun­able 21⁄2 -inch King free-bleed by­pass reser­voir shocks at all four cor­ners. The lift is de­signed to al­low fit­ment of true 35x12.50 tires on the stock alu­minum GM 18-inch wheels with only mi­nor trim­ming. In­stal­la­tion re­quires slightly more than your com­mon hand­tools, but no weld­ing is re­quired and you can do it in your drive­way, fol­lowed up by a trip to the lo­cal align­ment rack.

11The JD Fabri­ca­tion mid-travel kit for2011-to-cur­rent GM HD front sus­pen­sion starts with fab­ri­cated up­per A-arms made from laser-cut, MIG-welded mild steel. The de­sign of the arms al­lows for 2 inches of lift via cranked or keyed tor­sion bars and 2 inches of ad­di­tional sus­pen­sion down­travel.

44 The 21⁄2-inch King shocks in­cluded with the kit fea­ture JD Fabri­ca­tion–spec valv­ing and spe­cial off­set lower mounts to clear the CV 4x4 axle­shafts. The free-bleed by­pass tube al­lows for po­si­tion-sen­si­tive ad­just­ment that you can tune to your lik­ing. Turn­ing the by­pass screw firms up the sus­pen­sion com­pres­sion and re­bound; loos­en­ing the screw soft­ens the com­pres­sion and re­bound.

33OE-style rub­ber bush­ings are uti­lized on the frame end of the JD Fabri­ca­tion A-arms. This re­duces the amount of noise and harsh­ness trans­mit­ted through the sus­pen­sion and frame into the cab. These bush­ings are de­signed to last 100,000 miles or more and don’t squeak, rat­tle, or re­quire any main­te­nance like some af­ter­mar­ket al­ter­na­tives out there.

22 In­stead of a tra­di­tional ball joint, the JD Fabri­ca­tion A-arms fea­ture cus­tom high­misalign­ment EMF uni­balls. They are com­pletely re­build­able, and no drilling is re­quired for A-arm in­stal­la­tion. The ta­pered shank matches the ta­pered hole in the fac­tory GM knuckle.

Newspapers in English

Newspapers from USA

© PressReader. All rights reserved.