After my ill fated heim jointed steering linkage, I decided I wanted to try something else. I had 2 major problems with the F150 knuckles and the heim jointed steering. The first was the F150 knuckles are 1"-2" lower than the Bronco knuckles which resulted in bending my "indestructible" tie rod. The 2nd was the way I had the drag link attached to the tie rod created some nasty steering wobbles. At the Puyallup 4x4 Swap Meet in March 2000, I found a set of Scout II Dana 44 disk brake steering knuckles that looked interesting. The steering arm comes out very high on them, providing additional clearance and they also use 2 holes in the arms, instead of just one. The picture below shows the differences between the F150 knuckle on the left, stock Bronco drum knuckle in the center and the Scout knuckle on the right.
Originally, I planned to use the 2nd hole for attaching the drag link, but on further thinking, I determined that I would have to make a longer pitman arm in order to retain the same turning radius capability. I thought about going with a Performance Unlimited type of approach to the tie rod and drag link, but with the Scout knuckles as high as they were, I couldn't stack them the way other people do with this type setup and I didn't want to mount the tie rod below/drag link above since I wouldn't be getting all the height possible from the Scout knuckles. About the time I was getting ready to start fabbing up my new steering links, talk on the list turned to the Chevy Blazer tie rod and drag link setup. This setup had been mentioned before, but at the time, I was still happy with my heim jointed stuff and didn't pay much attention to it. But the more I mulled it over, the more sense it made. I get easily replaced Chevy components, parts that are designed to be used in a steering system, the opportunity to make strong tie rod and drag link tubes and best of all, I didn't have to make a longer pitman arm to make it work.
I was reluctant to put the Scout knuckles in service at first. After several inquiries to the lists, there were only a couple people who were using them. And the ones that were using them kept the Scout outer stuff (calipers, rotors, hubs, external locking hubs). All I had was the Scout knuckles and I didn't really want to track down the rest of the Scout stuff, so I decided to see if I could use my existing F150 brake stuff. Unfortunately, the Scout knuckles use the smaller spindle hole, not the big F150 type hole. They also use an 8 hole mounting pattern instead of the Chevy style 6 hole pattern. It then occured to me that I could do the Chevy type disk brake conversion instead of the F150 style. All that I would have to do would be to redrill the 8 hole pattern to a 6 hole pattern (2 of the holes already line up) and get the Chevy spindle, backing plates and calipers.
Before I fully comitted to the conversion, I decided to see what the tie rod would look like it its new position. The pictures below show where the tie rod would be with it mounted below the F150 knuckles, above the F150 knuckles and above the Scout knuckles (mocked up with washers here).
That's more like
it!!!
Tie rod height at full spring compression. I raised
my bump stops 3" to solve this problem.
It looked possible to me so I headed out into uncharted waters (at least I thought I was being original at the time). Essentially, there is nothing that fancy about the swap other than the Scout knuckles. It is the standard Chevy disk brake conversion that many people have documented. The Chevy parts are mid 70's Blazer stuff including spindles, backing plates, calipers and flexible brake lines. The Ford stuff is 76-80 Bronco/F150 hubs, rotors, bearings and seals. I didn't do anything fancy with the axle shafts. They're just the same early Bronco heavy duty shafts that I've had for a few years. The picture below shows the height of the tie rod relative to the differential housing.
Of course, there were a couple obstacles to overcome. By putting the tie rod on top of the Scout knuckles, my drag link became almost flat. The angle difference between my drag link and track bar was very pronounced. I decided I would need to raise the track bar mount on the axle housing to reduce the amount of bump steer that I may get. I also determined that I needed to raise my bump stops 3". This raise in the bump stops does not effect up travel since my coils get to full compression about the same time anyway. I raised the track bar mount 4.5" which was taking advantage of the raised bump stops. The angles are a lot closer now, but the drag link is still flatter. One thing to note on the Chevy drag link is that it will end up about 6" longer than stock which tends to flatten it out too.
The steering linkages are made using 1985 Chevy Blazer tie rod and drag link ends. The drag link ends are neat because they have about double the amount of travel of the standard tie rod end. I bought mine through Autozone.com which had really good prices.
Autozone Online Prices:
ES2233L $25.99 (draglinks)
ES2234R
$24.99
ES2027L $24.99 (tie rod ends)
ES2026R $24.99
For the tubing, I used 1.5" OD x 1/4" wall DOM and then bored it out to accept some threaded rod end adapters. I only did this since I had the adapters and tubing already purchased. If I had to do it again, I would go with either 1.25" OD x .281 wall DOM or 1.5" OD x 0.344" wall (11/32nds). This way you can run the tap directly into the tubing and won't need any threaded adapters. The Chevy stuff does require some special tooling. You need a 7 degree tapered reamer and 7/8"x18 right and left hand taps. I split the cost with a few other guys to help on this one. They were kind of expensive but of course since I bought them, some new sources came up which would have been a lot cheaper.