I TOTALLY ENJOYED the December article on steering failure and I hope that in a follow-up you can include something on the steering box. I have a ’51 Chrysler 331 that has extensive play in the steering wheel while the car is standing still with the engine off and while it’s on the road. The ball joints seem in order and the inner and outer tie rod ends have been replaced. In driving, the car tends to wander and at 50 mph a severe shimmy develops. I have “tightened up” the play in the steering box as far as I could go but little seems to have improved. Is there anything that can be done other than removing this monster and having it rebuilt?
Here’s the reply from John Armstrong, author of the article:
My first question would be is the lost motion you’re experiencing indeed in the steering box or is it somewhere else?
The excessive play in the wheel could be all in the steering box, in a loose linkage component or a combination of both. You mentioned that you’ve replaced the inner and outer tie rod ends, so that eliminates a fair amount, and the ball joints themselves wouldn’t be an issue with regard to this problem. The idler arm in your steering linkage is a good place to look for lost motion. Its function is to support and pivot with the steering linkage, and is often secured to the frame rail opposite the steering box. This type of joint should pivot, but not allow up or downward movement. If it does, this would account for some or possibly all of the play you are experiencing. If you have a shop manual it will identify the steering linkage components and whether they can be adjusted (to tighten them up), or must be replaced. A good plan of attack is to start your inspection at the steering wheel and follow movement through the steering box, the linkage and, finally, to the wheels.
The Approach I Would Take
Have a friend move the steering wheel slowly from side to side until resistance is felt, while you look under the hood. Watch the steering shaft exiting the column, and the mounting flange that connects it to the steering box. If all seems to be moving as one, and no looseness is noticed, continue the inspection on the exit side of the steering box, at the sector shaft where it’s connected to the pitman arm. At this point you will most likely need to be under the vehicle to continue the inspection. Have your assistant continue with the same steering wheel duties while you watch the sector shaft coming out of the steering box. If there is a tremendous degree of steering wheel movement before any movement is seen at the sector shaft, then you have certainly established that the steering box will require service. A maximum of two inches of back-and-forth play in the steering wheel is generally considered acceptable, but if your shop manual states otherwise, go with that.
Note: If you have power steering, you should start the engine and have it idle while making this inspection on the steering box. Be cautious; watch out for the fan and other moving parts while doing this. Also, should you need to raise the front of your vehicle, use the typical safety precautions such as properly placed jack stands and wheel chocks.
Even if you found extensive play in the steering box, continue inspecting the remainder of the linkage, as you may find additional problems. Once again, have your assistant move the steering wheel back-and-forth until you start to notice steering linkage movement. Any connecting joints should only pivot as the linkage is moved. You shouldn’t see any joints flexing side to side or any up-and-down movement. Don’t be afraid to push up or pull down on any segments of linkage as a means of inspection—they shouldn’t move. Finally, verify that the wheel bearings are properly adjusted. If, after doing this, all indications point to the steering box, verify that it is indeed adjusted properly following the shop manual procedure for your vehicle. Typically, there is an adjustment to remove both the worm shaft and sector shaft endplay.
On some earlier GM vehicles they reference using a “scale” to measure how much pull is required to move the steering wheel.This is basically a simple “fish” scale connected to the spoke of the steering wheel next to the perimeter rim. With 1960s vintage GM vehicles, they reference using a torque wrench connected to the steering wheel nut for the same test. Yours will likely be a similar test.
Regarding the Shimmy & Wandering
1. Inspect the condition of both front tires and wheels: Make sure the tires are properly inflated, and then take the car on a short drive to round them out. Return home and raise them off the ground, either one at a time or together. Once the vehicle is safely secured, rotate the tires by hand and observe. You are interested in both the radial and lateral run-out. Placing a cinder block (or something similar) close to the tire will work well as a visual guide. The maximum allowable run-out is usually considered to be .060” (or 1/16th”), although you might get away with a little more. What you will be looking for here is something that’s blatantly obvious, possibly a bent rim. If you are running radial tires, look at and feel around the tread for any abnormalities. A bulge in the tread indicates a separation, and the tire will require replacement.
2. Balance: Once you confirm that the tires and wheels are in good condition, verify that they are properly balanced. This should be a simple process what with all the high-tech equipment that is out there. Unfortunately, a lot of it isn’t calibrated as frequently as it should be (if ever). Deal with someone you know, and don’t hesitate to ask how frequently the machine is checked.
3. Toe-in adjustment: You indicated that the tie rod ends have been replaced, so it would be worth re-checking the toe adjustment. This could also be causing problems for you. I found 1/32” toe-in listed for 1950 model Chryslers, and 0- 1/16th” toe-in for 1953-55 models.
I don’t have a book that shows the specs for 1951, but judging by the measurements for the other models I think it’s safe to say 1/32” toe-in is the “desired” setting, with the acceptable range being 0- 1/16th” toe-in.