Front Springs

When I bought my truck, the front end was sagging pretty bad. The right front spring tips curved down! I searched for some springs and got some advice from a couple of local places. Now that I have collected a list of vendors from coast to coast, I think I could have done better. Below is a description of my first spring solution. Following that is a description of my second solution, which is still in testing. I'll add some more text when I have a better informed opinion.

1st Solution

I replaced some missing clips within a month or two of getting the truck, and at that time I noticed that the right front spring actually had an inverted arch. The ends were lower than the middle. The left front was almost flat.

When I got it, the truck had some old bias-ply retread tires on the original 16x5 rims. I drove on them for over a year, but eventually they started to throw tread. Since the rims were in bad shape, they needed to be replaced too. In May of '97, I got 31x10.50's on 15x8 rims. The tires hit the edge of the fender when going over rough, axle twisting bumps and dips. I knew I needed to fix the front springs.

I could have the springs rebuilt for $150 to $200, depending on how much had to be done. This would include re-arching, replacement of damaged leaves, new bushings, etc. The spring shop wouldn't know exactly what was needed until they took them apart. Another spring shop said they would "level" it for about $100. This would probably involve re-arching or adding a leaf to the lower side.

I checked on new springs and found some confusing recommendations. One shop said I could use the same front springs and CJ's. When I called the technical line at Rancho, they said the pickup trucks used a heavier spring than the CJ. They had one that would give a 2 1/2" lift. Since my tires were rubbing the fenders, this seemed like a good choice. I called other 4WD specialty shops that used other spring manufactures, like SuperLift, SkyJacker, etc. but it seems that Rancho is the only one that makes springs for these old Willys trucks. I guess they were the first in this business, and back when they started, these trucks were a significant market for them in the early years.

I learned that leaf springs are specified by

  1. number of leaves;
  2. width of leaves;
  3. length eye-to-eye straight;
  4. free arch (unloaded);
  5. arch (don't know for sure but this may be stationary with curb weight on flat surface); &
  6. pounds per inch of deflection.
The Rancho 16243 is a 4 leaf, 1 3/4" in width, 36.7" in length, 4.xx" free arch, and 3.6" mounted arch, and takes 711 lbs. per inch of deflection. For contrast a similar spring for a CJ has deflection of 353 lbs. / inch.

Rancho had no springs for the rear of a Willys Truck. My rear springs (stock?) are 2" wide and 60" long. When I worked on the rear axle, I got a new main leaf, new bronze bushings, new pivot bolts, and one new shackle.

I finally decided to buy the Rancho springs, almost a year after my first research. My local 4WD shop had them in stock so I picked them up. I bought a steering stabilizer a few days before, but I didn't buy the shocks at that time. I wanted to put the springs onto the vehicle and measure them before I bought shocks. The sales clerk said the book showed no shackle recommendations, so we assumed the springs would connect to the stock shackles. I didn't get to install the springs that weekend, because I was working on my other vehicle.

In this picture, you can see the difference between the arch of the old and new springs.

After waiting about two weeks, I finally started to pull things apart on Friday afternoon about 3:30. I had false hope of riding the next day.

I have some deep sockets and a 20" breaker bar, so the U-bolts really gave me very little problem. I soaked them with Liquid Wrench and then twisted them off. Well, the nuts on 3 U-bolts came off OK, and I just twisted the ends off the other U-bolt. I had to buy a new U-bolt, but one cost about $10 and I could get a set of 4 for about $20. so I got four new U-bolts.

Since I had the axle essentially free of the frame, I pulled the steering linkage, dropped the front drive shaft, disconnected the brake lines, and carried the axle into the garage from the driveway. Man that thing was heavy! My back still hurts thinking about it.

I opened up the differential to see how it was inside. This may seem unnecessary, but last month I blew a bearing in the rear diff and I figured as long as I had it this far, I might as well find out the condition of all the hidden parts. The pinion and diff bearings were fine. I took apart the knuckles and found the kingpin bearings were shot.(more on the knuckles)

My Jeep had "C" shackles on front, and the Rancho book didn't say anything about needing shackles with these springs, so I didn't buy any originally. But the new springs could not be mounted on the "C" shackles. The eyes were too small. I got new shackles and new pivot bolts for the spring mounts.

It took several hours to clean all the "grease soaked manure" off the front axle. (This was a farm truck for over 40 years.) I had worked for about 5 hours on Friday, quitting at about 11 pm, and about 8 hours on Saturday, from 6 am until 2 pm. Then I ran to the parts store for the new U-bolts and shackles. I had other commitments the rest of the day and Sunday. Monday I went to work late, after looking for kingpin bearings at several parts stores. My son and I spent about 3 hours Monday night, 2 hrs each evening Tuesday, Wednesday, and Thursday. By the end of the evening Thursday, the axle was back under the truck, but not bolted on. The new U-bolts were larger diameter than the old bolts and our 1/2" drill bit was too dull to drill out the plates and shock mounts (which bolt on beneath the plates). Finally I took Friday off from work to finish this thing. I got a new bit, drilled out the holes, put the new bolts on, attached the new steering stabilizer, attached the drive shaft, attached the break lines and bled the brakes.

I didn't buy shocks at the time I got the springs, because I wanted to measure the travel first. I'm glad I did it that way because the maximum length of the recommended shocks was 18+". With my truck sitting on flat pavement, I measured 18 1/4" between the center of the upper and lower shock mount. I got some longer shocks and put them on. By the time we finished it was after dark, so we took it for a test drive on the pavement, and played a game of racquetball as relief from a long week of mechanic work.

In the morning, we sanded and primed over a couple of rust spots and took it for a ride in the mud pits. I'm in southern Arizona and it doesn't rain between April and July, so the mud pits are powder dry. But we stirred up a lot of dust, and climbed every hill except one where someone had made a big wheel hole. Since I don't have lockers, I lost traction when my right front tire dropped into the whole, and my left rear tire came up as the vehicle rocked, so all my torque was going into the air. I successfully went through several big wheel dug holes and crossed a deep washout in one track. I crossed it at an angle and as the left front wheel dropped into the gully, the right rear wheel raised over a foot into the air. For all that, I couldn't twist the front axle far enough to rub the 31x10.50's on the fenders. This old truck is awesome!

The springs were supposed to give 2 1/2" of lift, the left front clearance between axle and bump stop went from 3" to 6", and the right went from 2" to 6". Obviously my old right front spring was shot. I knew that by the inverted arch. But my old left front must have sagged 1/2" too. With the new springs, it rides quite stiff, even with the new Rancho 5000 shocks. I think the springs are heavier than the stock springs. It rides like an off-road truck, and it goes like one in the dirt too.

I spent a total of over 30 hours, but more than half of that was on the axle. Not messing with the axle, I would guess that you'd be lucky to get the new springs on in a single day. Especially if you have to run back to the store twice for more parts like I did. I figure the suspension was about $325 in parts.

I'm ready for the mountains of AZ!

Rick 6/24/97

2nd Solution

There were two problems with the Rancho springs.

  1. They were Stiff.
  2. They were only available for the front.

As I said, the Rancho springs were very stiff. Some people say that the stiff springs are better for vehicles with a heavy engine, like a big V-8. Paul Barry of Willys America said he had seen Willys vehicles with Rancho springs and cracked frames that he attributed to the springs stiffness. My rear springs were as probably as stiff as the Rancho springs but with a lower arch.

Since Rancho doesn't make a spring for the rear of a Willys Truck, the front of my truck sat a couple of inches higher than the rear. I thought of getting some custom springs made to match, but that would cost more than the Rancho springs did. I thought it might be throwing good money after bad.

I found that I could get new springs made to the original specifications from Walck's (and probably other places too). My holdup was those fat tires.

Radial tires ride much better than bias-ply. They don't get flat spots when they sit, and they don't follow every minor ripple in the pavement. You can air them down for better traction on sand. They take less energy to roll (as measured by my legs push-starting the truck in exactly the same place several times with radial and bias-ply -- don't ask!). But the 31x10.50 tires on 15x8 rims stuck out past the fenders almost two inches. It was great fun to throw mud on those rare occasions when we have mud here in the desert, but throwing mud makes a mess of the windshield and hood and mirrors and steps and bed and roof. Man! That mud was everywhere! So I decided to go back to narrower rims and tires. I bought a set of 15x6 rims from a mid-seventies Jeep at the junk yard. They fit on OK, and I mounted a 31x10.50 on one as a spare. Before I got around to buying new tires for the rest of the 15x6 rims, I found a guy who wanted to get rid of some 16x5 rims. He wanted wide rims. I wanted narrow rims. We swapped.

The 2 1/2" of lift was necessary for the wide tires. Without the wide tires, I didn't need the lift anymore. So I could get rid of the stiff springs. I put on springs from Walck's. They are 10 leaves instead of 9 like my original spring.

I haven't driven on them with new tires to judge how well I'm doing with my second solution. I'll update this page soon.

Rick 11/3/98

© Richard B. Grover 1997 to 2006. Last updated: Friday, November 6, 1998