Since the return of The Beast, I've noticed a slight vibration in the driveline. Not enough that it will rattle your teeth, but enough to know that something isn't right. Turns out the lift was too high and the driveshafts were at too extreme an angle. The reason for this is simple enough... the truck was level when purchased. We put in a heavier motor (the Cummins 4bt diesel) and had to replace the front stock springs with Old Man Emu 2766 Front Extra Heavy-Duty Springs (2766) to support the weight. When we replaced the diesel with the Chevy LT1 V8 350 (a lighter motor), the front end of the Defender rode higher than the rear. It was not level. So, we leveled it out with some spacers at the rear. Unfortunately, that made the rig taller, unstable and changed the driveshaft angles. The Beast had to be lowered back to where it was when the shaft angles were set, so at the recommendation of hard-working Land Rover lover Luke Miles at The Shop, who spent a couple of hours researching the proper springs for this custom conversion, I purchased Old Man Emu 2751 Front Heavy-Duty Springs (2751) from Expedition Exchange.
Tom's 4x4 in Chattanooga did the installation yesterday and had me on the road in about two hours. They replaced the front springs and removed the rear spacers, effectively lowering the rig about 1.5 inches from its overly tall and unstable previous height. It still has lift, but has lost that scary top-heavy lack of control from being too high.
The ride is MUCH improved. It doesn't try to get away from me when I brake hard, it doesn't lean out too far in corners, and it doesn't rock or sway. It's much smoother, more stable and a LOT safer (that one's for you, Mom!) :)
The only vibrations now are the rumble of the motor and the grumble of the mud tires. I'll eventually bring even that down a bit when I get around to switching the Treadwright Guard Dog M/T tires (using the Goodyear Wrangler tread) for Treadwright's Warden All-Terrains (BFG All Terrain K/O tread). FYI... Treadwright is an awesome manufacturer of retreads. Now, don't get all snobby about using retreads. They are every bit as good as the originals at half the price. And Treadwright will deliver them to the shop of your choice. Here's a little clip I did for them during our Carbon Neutral Expedition in 2010: