Stock drive shafts frequently become problematic for Samurais with four or more inches of lift. A plain SPOA or a set of three inch lift springs with taller shackles is about the limit for their length. To avoid expensive custom drive shafts, aluminum drive shaft spacers that bolt between the stock drive shafts and the pinions-ranging in size from 0.75 to 1.5 inches-are available from several Suzuki aftermarket vendors. These are designed to prevent over-extension of the slip yokes and a separation of the two halves of the shafts.

However, there are two problems with the stock drive shafts when they are used in a suspension lift, and the spacers only address one of them: length. With drive shafts as short as the Samurai's, the angle between the axles and the transfer case quickly becomes excessive for the universal joints. Drive shaft spacers do nothing to reduce this angle because they do not lengthen the drive shafts; they lengthen the flanges. Accelerated wear, increased vibration, and even binding can occur when the U-joints are forced to soak up the extreme angle from a lift over six inches with stock-length drive shafts.

Trail Tough Suzuki Stuff in Medford, Oregon has developed an affordable, elegant solution for up to eight inches of lift without the need for custom drive shafts. Their extended slip yokes are made from modified Samurai drive shaft slip yokes, available in either one or two inch longer sizes, allowing for an increased suspension lift and lengthened wheelbase. Addressing both of the shortcomings of the stock drive shafts in a lifted Samurai-length and angle-Trail Tough has maximized the utility of the stock, inexpensive drive shafts and U-joints.

My Samurai has about eight inches of lift and a slightly lengthened wheelbase from the addition of a 4.5 inch SPOA, two inch longer springs front and rear with 1.5 inches of lift, and another one inch of lift from the Missing Link shackles. With a 1.5 inch spacer on the rear drive shaft and a pair of spacers (0.75- and 1.0-inches) on the front, I was tired of the vibrations and the need to replace universal joints every 3,000 miles. I thought I needed a pair of expensive, custom drive shafts, but when I found out about Trail Tough's solution, I decided to give it a try.

And I am glad I did!

I contacted Brent Bradshaw at Trail Tough and ordered two 2-inch slip yokes. He warned me that the two inch longer slip yokes are quite long, but with 1.5 inches of spacers in back and 1.75 inches in front, I thought I would be all right. One look at the new slip yokes and I knew they are of very high quality. Installation was no different than installing a stock slip yoke with a new U-joint. I noticed, however, that while the front slip yoke was the perfect length, the rear didn't have very much compression travel left in the splines. I compressed the suspension in the garage and it appeared as though the length of the exposed splines was sufficient.

On the road, I immediately noticed that the vibrations caused by the U-joints were very significantly reduced. It was almost like driving a stock Samurai again, in terms of smoothness! Comparing the U-joint angles with the drive shaft spacers and the extended slip yokes, I could see what a difference the longer yokes made. Every little bit of reduction in the angles helps significantly!

However, on my first trip off road I flexed my suspension on some rocks and almost immediately destroyed a rear U-joint. The bearing caps in the new slip yoke were cracked and the needle bearings destroyed because the two inch extended slip yoke in the rear shaft was too long and had been over-compressed. I made the mistake of driving back home from the trail, which wound up slightly damaging the yoke itself.

I contacted Trail Tough again and explained the problem. Even though he had warned me beforehand about the two inch slip yoke possibly being too long, he was gracious enough to exchange my slightly damaged two inch slip yoke for a brand new one inch slip yoke. Trail Tough's customer service is of the same quality as their products!

With the new slip yokes of the proper length, I have been extremely pleased with the product. Mine have taken my Samurai through trails in Oregon, California, and Arizona without any breakage, and so far my U-joints have lasted thousands of miles as a daily driver without needing replacement. Drive shaft vibrations have been significantly reduced, and I saved a ton of money over buying a pair of custom drive shafts at $300 or more apiece.

While being a great solution for mild and moderate suspension lifts, there is still a limit to the amount of lift that these extended slip yokes can handle. The design of the universal joint itself can only accommodate a certain degree of angle before it reaches its limitation. Thus, Trail Tough's slip yokes are designed to maximize the utility of the stock U-joints, not to cheat the laws of physics. At some point between eight and ten inches of lift, the stock drive shaft with these slip yokes reaches its limit. If I replaced my 1.5 inch lift springs with three inch lift springs, my u-joint angles would be enough to cause a major increase in vibration.

For mild to moderate suspension lifts (that's most of us!), Trail Tough's extended slip yokes are a great solution. But for extreme Samurais with ten or more inches of lift, Birfield or CV-type drive shafts become a necessity. Trail Tough asks only $65 each for either a one inch or two inch extended slip yoke with a core exchange of your stock slip yoke.

--Geoff Beasley