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Fixing the Silverado HD’s Weak Link

PPE Diesel Extreme-Duty forged steering system.

Apr 10, 2020

GM's late-model pickup steering system is a notorious weak link. While sufficient for stock highway use, as soon as any larger tire is added, any off-roading is done, or the power output is increased at all, failure becomes imminent. On Sierra and Silverado 2500HD and 3500HD trucks, as with our Silverado 2500HD, there are a few common failure points. The undersized tie rods are the most common culprit. Also prone to premature wear are the pitman and idler arms. And under the most extreme use, the center link can become bent. Fortunately, there are a lot of options for upgrading the steering on GM pickups, including the incredibly robust Extreme-Duty forged steering system from PPE Diesel.

Designed to fit 2001-2010 Chevy Silverado and GMC Sierra 2500HD and 3500HD pickups, the kit from PPE diesel features massive 1.5-inch forged steel tie rods, 1.5-inch forged center link, and forged pitman and idler arms. Selecting the kit also gets you a pitman arm puller. However, if you prefer to upgrade as you go, all of these parts are also available individually, though you do save about $100 buying the kit. The "Stage 3" forged tie rods can be used with all factory components; however, the forged pitman and idler arms utilize a larger 7/8-inch bolt and require either drilling of the factory center link or replacement with PPE's forged center link. If you don't want to mess with the pitman or idler arms, PPE offers the forged center link drilled for the tapered factory joints. Also available as an add-on to the kit is the company's forged idler support.

Photo 2/24   |   When we started our 2002 Chevy Silverado 2500HD project we knew that the end goal was to have a fair bit of power and 37-inch tall tires. We also knew that the factory steering ultimately needed to go. With this in mind we hit up the experts at PPE Diesel and opted for one of the company's forged steering kits.

While all trucks will need these parts replaced at some point, whether through simple wear and tear or from failure, we decided to get ahead of the curve with our 2002 Silverado 2500HD. With a modest 700 rear-wheel horsepower and 37-inch tires, we wanted the stoutest steering we could find. Along with replacing the steering box, we were able to install PPE's Extreme Duty forged steering system in our driveway in about half a day. Our truck is rust-free, and we cut a few corners by removing the tie rods and center link as a unit, instead of individually, so your experience may vary based on age an experience. The only specialty tools needed are a pitman arm puller (if you're not replacing the steering box), and a very large adjustable wrench (we used an 18-inch wrench).

Because the PPE steering parts retain the factory geometry, we've noticed no detriment to our truck's drivability. The truck tracks straight as an arrow and the steering feel is nice and firm with very little of the wander that's all too common with this generation of pickup. We did have to shorten the tie rods just a touch, but that was due to the BDS steering knuckle that was installed on the truck, factory trucks won't require this step.

Photo 3/24   |   Our 2002 Silverado 2500HD test subject already had tie rod sleeves installed, as seen here. However, as you can also see even with the sleeves the tie rods are still woefully undersized.
Photo 4/24   |   To start the PPE forged steering install we first removed the truck's tires and supported the front end on jack stands. We then popped the tie rod ends off of the truck's steering knuckles. If for some reason you're reusing the tie rod ends, a brisk whack to the knuckle with a hammer will free the joint. If you're not reusing the joint, it's easier to just give the joint a quick tap on the threads to break it free. Also, because we were planning to replace the center link as well, we left the tie rods on and dropped the whole unit. If you're just doing tie rods, it takes a very large wrench and a lot of pressure to break the inner tie rod joint free of the center link.
Photo 5/24   |   As part of our steering system refresh, we also needed to replace the steering gear box. To remove the steering box, the high-pressure oil lines need to first be removed from the top of the box. Seen here, the hose fittings are accessed by removing the inner fender liner and reaching above the frame with a box wrench.
Photo 6/24   |   Three bolts on the outside of the driver side frame rail attach the steering box. These bolts thread into the steering box, so a wrench (or preferably and impact wrench) is needed only on the outside.
Photo 7/24   |   Once the three bolts are loosened, and with the fluid lines and center link removed, the steering box can be lowered out the front of the truck. While it's a tight fit, it will wiggle itself past the sway bar so there's no need to remove it. Because we were replacing the pitman arm with a PPE forged unit, we left it on the box. If you need to reuse the pitman arm, it's easiest to remove it from the box out of the vehicle. If you're just replacing the pitman arm and not the steering box, you should still remove the steering box, as it's incredibly difficult, if not impossible, to remove it in the truck.
Photo 8/24   |   We opted to replace our worn-out steering box with a new AC Delco unit from RockAuto.com (right). RockAuto.com got us the box quickly, and the price was hard to beat. We're confident that for our usage, and with the forged PPE parts, the new AC Delco box will last for many years.
Photo 9/24   |   The PPE Extreme-Duty forged pitman arm is perfect for those looking for the ultimate in strength. It's designed to take the abuse of big tires, big horsepower, and those wicked boosted launches at the track.
Photo 10/24   |   Part of the magic of the PPE Extreme-Duty forged pitman arm lies in its dual, replaceable, spherical bearings.
Photo 11/24   |   The PPE Extreme-Duty forged pitman arm also uses a larger 7/8-inch bolt for increased strength in attaching to the center link. This means that the factory center link either needs to be drilled out to fit the new bolts, or PPE's forged center link needs to be used.
Photo 12/24   |   If you look closely at the pitman arm splines, you'll see there are three that are larger than the others. These three splines work to locate the pitman arm on the steering shaft, so there's no way it can be installed incorrectly.
Photo 13/24   |   For ease of installation, we bolted the new pitman arm to the steering box prior to installing it in the truck. The new steering box installs in exactly the reverse order of removal.
Photo 14/24   |   Along with the pitman arm, we also replaced the idler arm. The idler arm and idler arm support bracket are another common weak link in the steering system. The easiest way to remove the idler arm is to remove the entire assembly, which is held in place with two bolts.
Photo 15/24   |   To compliment the Extreme-Duty forged pitman arm, PPE also offers an Extreme-Duty forged idler arm (lower). These too feature replaceable spherical bearings and a 7/8-inch bolt. PPE also offers a forged idler pivot assembly (the part the idler arm attaches to), however, it is so new that it wasn't available at the time we did this install.
Photo 16/24   |   Unlike the pitman arm, the idler arm isn't splined but is rather a press fit (because direction of installation doesn't matter). To get the idler onto the pivot assembly, it requires holding the center shaft with an Allan wrench while tightening the retaining nut with a box wrench until it bottoms out. While this can be done in the truck, it's tons easier with the pivot out.
Photo 17/24   |   With the new forged pitman and idler arms in place it is then time to install the center link. We opted to go the fully forged route and install PPE's forged center link. Because the name of the game is options, PPE offers a forged center link for trucks with factory pitman and idler arms, and one with 7/8-inch holes for trucks with the company's forged pitman and idler arms. The PPE forged setup is seen below the factory parts.
Photo 18/24   |   The PPE forged center link (bottom) is a massive 1.5 inches in diameter. The center link also features grease zirks for easy servicing of the outer tie rod ends and follows the same shape of the factory center link so there's none of the downsides of swapping to say a straight (race style) center link.
Photo 19/24   |   PPE offers three different levels, or "stages" of tie rods from sleeved stock up to these Stage 3 forged tie rods. These tie rods are a massive 1.5 inches in diameter, feature 2 1/3-inch ball joints at the knuckle, and a massively upsized inner joint. Along with those upgrades, the outer joint also uses a spring-loaded gusher bearing to maintain constant pressure. These tie rods are the ultimate in overkill, but we'll never have to worry about them again.
Photo 20/24   |   While working through the steering component installation, we made sure to coat the bolts that connect the pitman and idler arms to the center link with a copious amount of anti-seize lubricant. We also used thread locker on all the nuts and the inner tie rod threads. The last thing you need is a steering component either seizing up or falling off.
Photo 21/24   |   Remember that big wrench we mentioned earlier? We used an 18-inch adjustable wrench to tighten the new PPE forged tie rods to the center link. This is the same wrench we would have used to remove the factory tie rods should we have needed to. Aside from a pitman arm puller (if you're not replacing the steering box as we did) this is the only special tool needed.
Photo 22/24   |   While we were working on the steering, we also replaced the factory damper as well. There are several options for this, with the high-end being this Bilstein unit. Some people complain that the Bilstein damper is a bit too aggressive, tending to push the steering to the left. However, with how large of a tire we're running we haven't noticed this to be the case. On a truck with smaller tires a factory replacement would work just as well.
Photo 23/24   |   While the parts can be purchased from PPE individually, it's more economical to buy the whole setup as a kit. The only part not included from PPE is the replacement damper, which can be sourced from a local shop or RockAuto.com.
Photo 24/24   |   The finished product looks as burly as it is, though the only parts that are visible are the tie rods. Having everything in the steering system be new and forged adds a peace of mind that not even new trucks can offer. We're confident this is the last time we'll be replacing steering parts.


PPE Diesel

Rock Auto