Project Pathfinder Part 12, Fixing the Wobbly Steering for Good
We had just gone through the front suspension of Project Pathfinder a year ago in the hope that our mods at the time would tighten up its pathetically loose and wandering steering. Although our mods made a huge difference, after about 12,000 miles, a couple of off road excursions and a bunch of towing it became apparent that our front suspension would again need attention.
The stress of our big wheels and tires with a much more positive offset, was causing parts of our 130,000-mile old suspension to wear faster. Clunking noises came from the front end and the steering was getting loose. One drive of a newer ‘07 Pathfinder revealed that Nissan has come a long way in suspension design as well. Compared to the newer Nissan, Project Pathfinder felt nervous at highway speeds especially over bumps and cracks often found in the carpool lane on Southern California’s freeways. Bump steer was causing the truck to wander under these conditions – not fun when going 80 mph right next to the wall.
Upon inspection we found that our ball joints and tie rods were worn out, also our wheel bearings were wearing as well. Much to our surprise we also discovered that our brand new genuine Nissan center link and idler arm that we had reinforced with special bushings and braces in a prior installment of Project Pathfinder were worn out as well!
After researching more, it was apparent that even a mild suspension lift such as we had done and moderately larger tires such as our Project Pathfinder sported, greatly increased the strain on the stock steering linkage. Even a slight lift also greatly increases bump steer as well. Nissan off road forums are full of stories on how fragile the stock center link and idler arm are. There were many stories of failure of these parts even under mild off road conditions. Sometimes after only a few hundred yards of off road! We had underestimated what sort of steering issues we were going to have.
First we had to take care of the stuff that was simply worn. We replaced our wheel bearings with new genuine Nissan bearings and seals. That was simple enough. Our research also showed that the best ball joint and tie rod ends were not the usual genuine Nissan but NAPA Chassis parts. NAPA Chassis is NAPA’s top of the line suspension components line with a lifetime guarantee. It sounded good enough for us. On a Pathfinder the lower ball joints are a pain in the neck, requiring that the front diff be unbolted and lowered out of the way. So we took care of the ball joints, tie rod ends and bearings all at once.
To handle our steering woes, Calmini came to our rescue with their unique heavy-duty steering system. Now there are other brands of heavy duty steering systems for Nissan trucks but we felt Calmini’s system was the best for our needs because they address bump steer the best. Bump steer is caused when the suspension links and tie rod ends go through different arcs as the suspension compresses. The different travel paths cause the wheels to turn independent of the steering wheel, causing wander and instability.
The Calmini kit is a strong, well engineered piece.
Calmini relocates the tie rod pivot points to be closer in line with lines drawn vertically through the ball joints. The tie rod is also much closer to bisecting the angle between the upper and lower control arms of the suspension. What this means in layman’s terms is that the Calmini system geometrically eliminates over 50% of the bump steer by improving the suspension’s pick up points. None of the other steering systems do this; they are simply just stronger upgraded versions of the stock steering system.
Another really bad design feature of Nissans steering is the center link itself. It rocks on two tie rod ends attaching it to the Idler arm and the Pitman arm from the steering box. The other ends of the center link attach to the tie rods like a big dog bone. The center link can thus rock back and forth on the tie rod ends that connect it to the tie rods and Pitman and Idler arms. As the center link rocks like it will when traveling on bumpy roads, the toe will change over ¼ in. per side! Raising the suspension exaggerates the angularity of the center link and makes it worse. This is an amazingly bad design and it’s no wonder the Pathfinder wanders like a drunk when combined with the toe changes caused by bump steer.
The idler arm is huge including the bushings. It has over 3x the bearing area as stock.
The Pitman arm is many times stronger than stock.
The tie rods attach directly to the Pitman and Idler arm and the center link is now just a crossbar translating steering motion across the car. There is no dog bone to rock and upset the toe anymore at all. As a welcomed side effect, the steering is quickened by the Calmini system as well. Thus Calmini resolves both the bump steer and the center link rock issues with their excellent design, the only steering linkage manufacture to address this.
|Pitman Arm Installed|
Nissan steering components are known to be fragile, not Calmini! The Pitman and Idler arms are huge and beefy, cut from billet steel and over twice the size as the stock parts. The tie rod ends used are huge parts from a full size one-ton domestic application. The tie rod adjusters are stout solid steel parts, many times more beefy than stock. The center link is large in diameter and thick walled. The most impressive part is the problematic idler arm. It is a huge beefy part with huge bronze bushings three times bigger than the stock Nissan part. It is held in bulletproof double shear to the chassis by a beefy bracket. This part looks like it belongs on a F250SD more than a Pathfinder. If someone does manage to break the Calmini parts I have no doubt that the rest of the truck will be history as well.
We had to shorten our sway bar end links a little to clear the relocated tie rods to prevent contact when bottoming out the suspension. This was really no big deal. We also welded the bracket of our Rancho steering stabilizer to the center link because it was so fat the original clamps would not fit anymore. We tig welded this part and it was quite simple. Be sure and grease the idler arm and tie rod ends with an extreme pressure molly grease before driving. After the installation we took Project Pathfinder to Westend Alignment to have them work their magic on the suspension.
In driving Project Pathfinder, we were amazed at the difference. The steering is tight like a late model rack and pinion. There is a much more positive road feel and best of all, 90% of the wander is gone. The truck is secure and stable over bumps now. Cracks and bumps at high speed do not start the truck tramlining or wandering as before. Off road, nearly all of the steering kickback is eliminated as well.
The Calmini steering system has really impressed us; it is one of the coolest and feelable mods to date. In our estimation it is one of the most worthwhile mods we have done to date.
New Pathfinder? Nah….don’t think so.