Project Vehicross Part 8: Pinion Angle 101

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The one thing I4X does not account for is the parking brake cable. You will remember it was the first thing we removed when we started installing the new links. Because the I4X links are turnbuckled, any bracket welded to the links will move as you make adjustments. Bolting down these lines isn’t necessary (the parking brake will still work as the cable is hard mounted in other locations), but the cable will chafe on the links as you drive. Fortunately, a solution is just a hardware store trip away. We simply picked up a 2” round clamp to wrap around the lower link. We then bolted the original cable bracket to it and zip tied the cable in place. Using the clamp allows us to move the position of the cable when we adjust the length of the links. While maybe not the most elegant solution in the world, it’s worked for a year and a half!
 
Time to address the pinion angle itself. When setting pinion angle, it is very important that the weight of the vehicle is sitting on the axle. Luckily for us, the VX is tall enough to where we can work underneath of it with the wheels on the ground! We started off by finding a flat surface to measure the angle of the transfer case. We found a strengthening rib that was parallel to the output shaft and measured and angle of 4 degrees. If we were really anal, we would have removed the driveshaft and directly measured it off the output shaft flange. Note the hand needed to hold up the angle gauge since the VehiCross’s transfer case is made of aluminum.
 
On the axle side, we adjusted the length of the new lower links until we measured 4 degrees again. We actually got damn close just eyeballing it, but then used our angle gauge to ensure our eyeballs were calibrated properly. We used a tape measure to ensure we were setting both links to the same length so the truck didn’t have any weird tracking issues.
 
Along with the pinion and transfer case angles, it is important that the driveshaft itself has some angle to it (i.e. non-zero), otherwise more u-joint problems will occur. Clearly, this isn’t a problem on the VehiCross. But, if you’re setting up a very low car, it is something to keep in mind when setting up the suspension.

These lower links made a big difference with our driveshaft. After 10,000 miles of driving, we noticed that most of our driveshaft noises disappeared! However, once the truck got up to temperature, we did notice some familiar sounds again. We think that the lift is starting to overextend the driveshaft, and we do not have enough engagement in the slip yoke. It is also possible we need a re-balance since we have had the driveshaft apart for new u-joints. But, the I4X links have definitely been a major improvement and look awesome below our truck.

However, before we keep playing around with the driveshaft even more, we need to address the brakes! The brake pedal started getting very spongy and inconsistent and we ended up parking the poor VX for around 6 months. We aren’t sure if it’s the master cylinder or the booster that has quit, but they’re both getting replaced! While we’re in there, we’ve got a few other brake parts that need replacing, so we’re going for a near total overhaul! And, we promise this will take less than a year to write it all up too!

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