Re: Hard steering with and M-37

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: : I have an M-37 (53 Canadian version) with hard steering. : : It has lock out hubs and non-directional tires...basically : : what I have on my civilian PW that steers fine. I have : : tried adjusting the steering box, but slight adjustments : : in or out don't seem to make any difference. How much do : : you have to turn these to see a difference, and does : : turning it clockwise as viewed from engine tighten the : : clearance? : There are several places that can contribute to hard steering, including the steering gearbox. One note about adjusting the gearbox: The worm gear tends to develop more wear in a narrow central area (vehicle pointed straight ahead). If you tighten it too much at the most worn point, it may bind when the sector moves slightly to either side of that point. The geometry of many gear assemblies often creates more clearance as the follower moves off the center, but you can still experience binding immediately to either side of the worn area if it is tightened too much. Essentially, you want it as snug as possible without producing any binding along the full travel of the steering, lock to lock. The steering gearbox also needs good lubricant, proper bearing preload, good bushings, etc. If there is any significant wear in the bearings or bushings, or if the preload is set wrong, you won't be able to adjust the play out of the steering gear box. A badly worn worm/sector can considerably increase effort through the box. : If possible, isolate the sources of binding and friction by disconnecting the drag link from the pitman arm and checking the gearbox without a load attached. Of course, it will act somewhat different when not under load, but you'll get an idea, at least, as to whether the box is contributing more than it's share of friction to the steering. : With the linkage disconnected from the pitman arm, jack up the front axle and manually turn the wheels back and forth, watching for looseness and feeling for any binding or roughness. Again, try to isolate each glitch and nail it down. : Another hint: Even though you may see grease ooze out of a joint when you lube it, it doesn't necessarily mean that the grease is getting everywhere it should. It may simply be following a narrow "path of least resistance" through the joint and leaving much of it dry. For permanently assembled ball joints, there isn't always a lot you can do, although sometimes it helps to warm up the joint a little and pump the grease through it with as much velocity as you can muster, then wiggle the joint around and repeat the process. Pumping solvent through it might be a possibility, but you are taking chances on damaging the seals. For joints that can be disassembled, no problem, just clean them, pack them with grease, adjust, and reassemble. : The steering knuckle is a common source of resistance, especially the lower tapered roller bearing, which tends to take a beating from both weight and any water in the knuckle. Proper shimming of the upper and lower bearings is also important. Newer trucks have ball joints at the steering knuckle that face the same direction and can thus split the load between them when the adjusting sleeve is torqued properly, but the M37 knuckle is set up so that the lower bearing has to carry the vehicle's weight. The upper one still has to handle the shock of stopping any upward action of the wheel, plus its stabilizing duty, but the lower one takes the brunt of it. If there is any stiffness in the tapered roller bearings, it will be magnified under load. : Even with a factory-perfect steering system, it still requires a fair amount of effort to turn these things. I'd suggest using full synthetic lubricants to try to reduce friction as much as possible. They also tend to be a little more tenacious in terms of sticking to the metal mating surfaces. : Regards, : Alan

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