I haven’t been entirely happy with the steering setup on my Suzuki Samurai. It had been modified from the stock setup, but I felt it could be much better and safer.
On a stock Samurai, the top steering rod (tie rod) that connects the steering box to the right wheel is a straight piece that sits on top of the leaf springs, along with the entire front axle. When the axle was relocated to the bottom of the leaf springs (a common off-road modification, called a spring-over-axle lift) the tie rod would rub on the leaf springs. You can see the old solution that I had in place in this picture - the bent rod replaced the straight piece in order to clear the leaf spring:
While the bent piece worked, it had two drawbacks:
1. It flexed, which created a very floaty, imprecise steering feel. It was reinforced with gussets to try to prevent flex, but apparently not reinforced enough.
2. I wasn’t confident in its construction. Steering is an important feature of any automobile, and this modified tie rod was essentially butt-welded, which is not the best method for strength and longevity.
With the help of a “pickle fork” (tie-rod remover), out comes the old rod.
The solution to the spring-over steering problem can be found in old Mercedes sedans. An old trick in the Samurai community is to bolt on a steering arm from an old Merc to bring the tie rod mounting point up entirely above the leaf spring, allowing the use of a straight tie rod.
The new steering arm bolts to the brake caliper mounting point. The Mercedes steering arm bolt spacing is very close to the Samurai caliper bolt spacing, but not quite a perfect fit. It requires a little elongation of the rear bolt hole to get the spacing just right. I used my drill press and a rotary file as a poor-man’s milling machine. It’s not great for the bearings on the drill press, but it works:
With a little bit nibbled out, I can test fit it on a spare caliper:
Note the longer bolts needed to accommodate the steering arm. They are the good stuff, special ordered in high-strength steel.
This might be a good time to mention the two different types of Mercedes steering arms used on their 70s and 80s sedans. The look very similar, but as I found out after I brought my first one home, they are a distinctly different shape and the taller one is needed for a Samurai steering conversion.
Correct arm is the tall one:
Correct arm at left:
With the steering arm bolted up to the caliper and steering knuckle, the battle is only half over. It still needs to be connected to the steering box. For this, I used the adjustable Mercedes tie rods from the Mercedes donor car and a chunk of 0.75 ID DOM tube.
The tie rods fit perfectly into the tube's 0.75" ID, and one of them is reverse threaded which allows adjustment of the length of the assembly by turning it.
I angle-cut the ends of the tube to make for longer, stronger welds. Welding is not particularly strong if the welds are short and the stresses travel perpendicularly to the weld (as would be the case with a straight-cut tube). Much better to have long welds that are oriented as closely as possible with direction of the stresses - mounted in shear rather than tension/compression.
I also drilled holes in the tube so that each of the Mercedes tie rods could be rosette welded (or plug welded) in four places, making the welds even more fool-proof for an amateur like myself.
One last touch before welding was to use a file to cut some flats into the tube. This is to accommodate a wrench on the tube, so that I can turn it and adjust the rod length.
Then it was time to weld! To get the length just right, I loosely installed everything on the truck and tack welded it in place. I really like to do as much fabrication as possible with things installed on the vehicle to avoid making things that don’t fit! You can start to see here how the Mercedes arm works to locate the tie rod above the leaf spring.
It was then removed and fully welded.
…and blasted with paint, and hung to dry. Then, finally, installed!
The tie rod is now clear of the leaf spring, very close to horizontal, and much more confidence-inspiring. A quick adjustment of the length gets the steering wheel pointed straight, then it is tightened up.
I’m really pleased with how this one turned out. The steering is much more firm, and I don’t feel like my truck might suddenly veer uncontrollably into oncoming traffic at any moment. It can also flex as much as it wants without the tie rod touching the leaf spring.
With these parts installed, my truck is now a collection of parts from a Suzuki Samurai, Suzuki Sidekick, Subaru Legacy, Ford Windstar, Geo Metro, Nissan 300ZX, Chevrolet Bel-Air, Honda Civic, and now it is also part Mercedes 300 sedan. Don’t park too close to it, or it might end up absorbing parts from your car too.
Cost:
$20 - used Mercedes tie rods and steering arms (Pick N’ Pull)
$20 - ¾" ID DOM tube
==$40
On a stock Samurai, the top steering rod (tie rod) that connects the steering box to the right wheel is a straight piece that sits on top of the leaf springs, along with the entire front axle. When the axle was relocated to the bottom of the leaf springs (a common off-road modification, called a spring-over-axle lift) the tie rod would rub on the leaf springs. You can see the old solution that I had in place in this picture - the bent rod replaced the straight piece in order to clear the leaf spring:
While the bent piece worked, it had two drawbacks:
1. It flexed, which created a very floaty, imprecise steering feel. It was reinforced with gussets to try to prevent flex, but apparently not reinforced enough.
2. I wasn’t confident in its construction. Steering is an important feature of any automobile, and this modified tie rod was essentially butt-welded, which is not the best method for strength and longevity.
With the help of a “pickle fork” (tie-rod remover), out comes the old rod.
The solution to the spring-over steering problem can be found in old Mercedes sedans. An old trick in the Samurai community is to bolt on a steering arm from an old Merc to bring the tie rod mounting point up entirely above the leaf spring, allowing the use of a straight tie rod.
The new steering arm bolts to the brake caliper mounting point. The Mercedes steering arm bolt spacing is very close to the Samurai caliper bolt spacing, but not quite a perfect fit. It requires a little elongation of the rear bolt hole to get the spacing just right. I used my drill press and a rotary file as a poor-man’s milling machine. It’s not great for the bearings on the drill press, but it works:
With a little bit nibbled out, I can test fit it on a spare caliper:
Note the longer bolts needed to accommodate the steering arm. They are the good stuff, special ordered in high-strength steel.
This might be a good time to mention the two different types of Mercedes steering arms used on their 70s and 80s sedans. The look very similar, but as I found out after I brought my first one home, they are a distinctly different shape and the taller one is needed for a Samurai steering conversion.
Correct arm is the tall one:
Correct arm at left:
With the steering arm bolted up to the caliper and steering knuckle, the battle is only half over. It still needs to be connected to the steering box. For this, I used the adjustable Mercedes tie rods from the Mercedes donor car and a chunk of 0.75 ID DOM tube.
The tie rods fit perfectly into the tube's 0.75" ID, and one of them is reverse threaded which allows adjustment of the length of the assembly by turning it.
I angle-cut the ends of the tube to make for longer, stronger welds. Welding is not particularly strong if the welds are short and the stresses travel perpendicularly to the weld (as would be the case with a straight-cut tube). Much better to have long welds that are oriented as closely as possible with direction of the stresses - mounted in shear rather than tension/compression.
I also drilled holes in the tube so that each of the Mercedes tie rods could be rosette welded (or plug welded) in four places, making the welds even more fool-proof for an amateur like myself.
One last touch before welding was to use a file to cut some flats into the tube. This is to accommodate a wrench on the tube, so that I can turn it and adjust the rod length.
Then it was time to weld! To get the length just right, I loosely installed everything on the truck and tack welded it in place. I really like to do as much fabrication as possible with things installed on the vehicle to avoid making things that don’t fit! You can start to see here how the Mercedes arm works to locate the tie rod above the leaf spring.
It was then removed and fully welded.
…and blasted with paint, and hung to dry. Then, finally, installed!
The tie rod is now clear of the leaf spring, very close to horizontal, and much more confidence-inspiring. A quick adjustment of the length gets the steering wheel pointed straight, then it is tightened up.
I’m really pleased with how this one turned out. The steering is much more firm, and I don’t feel like my truck might suddenly veer uncontrollably into oncoming traffic at any moment. It can also flex as much as it wants without the tie rod touching the leaf spring.
With these parts installed, my truck is now a collection of parts from a Suzuki Samurai, Suzuki Sidekick, Subaru Legacy, Ford Windstar, Geo Metro, Nissan 300ZX, Chevrolet Bel-Air, Honda Civic, and now it is also part Mercedes 300 sedan. Don’t park too close to it, or it might end up absorbing parts from your car too.
Cost:
$20 - used Mercedes tie rods and steering arms (Pick N’ Pull)
$20 - ¾" ID DOM tube
==$40
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