GM IFS AXLE BEEF
QI wrote to you before and greatly appreciate your advice. I recently stuffed 315/70R17 tires under my ’11 Chevy 1500. My question lies with my front centersection. I’m thinking about building a custom IFS front axle based off a Ford Dana 44 TTB centersection. I’ve got everything figured out for the build, but I have concerns about my Autotrac transfer case and the frontend spinning all the time with the deletion of the axle disconnect. I would also be adding a Detroit Truetrac limited-slip differential to the mix. I do moderate wheeling and I am not a rockcrawler or hard core. Do you think this would open a giant can of worms and should I just keep the front stock with the exception of new gears and upgraded axleshafts? I’ve got some other upgrades like steering lined up as well.
MICHAEL SIDORICK VIA FACEBOOK.COM/JOHNCAPPA4X4
AThe IFS GM front axles and steering have never taken a liking to larger tires and aggressive off-road use. The steering link failure is generally the biggest concern on the GM IFS 4x4s. Companies such as EMF (emfrodends. com) and JD Fabrication (jdfabrication.com) offer heavy-duty tie rods and ends that can cure that ailment.
It will certainly require some significant fabrication skills, but your TTB Dana 44 differential idea is a sound one. I wouldn’t worry too much about not having the axle disconnect. Although, you’ll likely want to use Cv-style joints for smoothness, rather than U-jointed axleshafts. The Eaton (eaton.com) Detroit Truetrac is a great limited-slip differential for mild offroad use. The gear-driven design means that there are no clutches to wear out and there is no need for special additives in the oil. However, I think it could potentially cause unusual steering input on the road in some situations, such as when cornering, even in two-wheel drive. You might be better off with an open differential, ARB (arbusa.com) Air Locker, or some other selectable locker with an open differential setting.
Ultimately, this kind of modification requires a lot of planning, measuring, time, and money. If you’re not currently blowing up the IFS axle and CV axleshafts, maybe stick with what you have. JD Fabrication offers 930-style CV axleshafts with adapters and RCV (rcvperformance.com) offers extra heavy-duty axleshaft replacements if the ’shafts are an issue in your application. With JD Fabrication or RCV axleshafts and heavy-duty steering links, you have covered the biggest issues with the GM IFS front ends. Maybe hold off on the TTB Dana 44 project until you start cracking the GM aluminum IFS axlehousing.