In modern cars, turning is almost effortless thanks to power steering, while older cars, which of course lack this little invention, require a little more oomph when cornering or maneuvering in an emergency. I think learning to drive in an old car and then using them for my first decade on the roads gave me an appreciation for expecting the unexpected, keeping the appropriate distances from other drivers, and taking one’s time. Of course, the latter probably developed more because the old car I drove was a bus which, let’s face it, doesn’t get anyone anywhere in a hurry.
In terms of maneuvering, the bus does surprisingly well and can make tighter turns than quite a few modern cars on the road, including our caravan. It’s large steering wheel compensates a bit for the lack of power steering as well as providing a nice support surface during long drives. However, buses are notorious for being difficult to keep traveling along a straight line. I think this is due to two main issues; the first and foremost of which is wind. When it comes to aerodynamics, the bus is the poster child of what happens when auto designers drink too much at lunch. It is a freaking box on wheels; a brick; mobile wall; or, as I’ve also heard so many times, a loaf (as is in bread). I have driven at 70 mph with a tailwind while getting 25 mpg, topped out at 50 mph with an incredibly low 10 mpg when traveling into a stiff headwind, and fought to stay in my lane, on the road even, to the point of physical exhaustion during insane crosswinds. Really, what was VW thinking when they decided to mass produce these incredibly beautiful, fun, amazing, useful, loveable, drivable toasters?
The second issue is worn out steering components. I think we tend to take for granted all the links in the steering system that transfer movement from the helm to the wheels of our vehicles. This system relies on many parts that act in unison, and, if a problem arises, it can trigger premature wear of associated parts and cause the apparatus to under-perform. Like a chain, the steering linkage is only as good as its most feeble segment and, for most buses, these chains have not been well attended to over the years. In some cases, failed parts are replaced but not ones that are well-worn. In other situations, nothing has been done at all. I once saw a forum thread, long lost in my memory now, in which a poster lamented the fact that some bus owners actually accept the poor performance of their buses (steering or otherwise) as a simple fact of driving a 40 year-old car. Shame on those owners for sure, and to prove the error in their thinking, all my buses have, for the most part, driven as they did during their younger days (things have broken/fallen off on occasion, certainly, but quite honestly that happens to my ’03 Jetta too).
Both Big Red and Big Blue had pretty responsive steering and aside from lubricating the front end, never needed much work (though I did replace Big Blue’s ball joints before I sold her). To my surprise, this was not the case for Moby. I say ‘surprise’ because the seller did not let me drive Moby very far or long due to the fact he had not registered or insured her. He did, however, replace the steering damper, ball joints, tie rods, and torsion arms, a huge plus in my book, but her steering was still sloppy to say the least. I could move the steering wheel about three inches from center in either direction before the front wheels did anything. This always took a few miles of driving to get used to, and I worried the police might think they were following an impaired driver until I finally got into the rhythm again. While I would not have put her on the road if I felt she was unsafe, driving Moby at times could be, well, a little white-knuckled adventure. This past winter, I resolved to root out the cause and bring her back within appropriate tolerances.
Let’s start by going through all the parts between the steering wheel and tires that could introduce free play into the system. The correct place to start diagnosing steering issues is at the steering wheel, followed by working along the linkage towards the wheels, looking and feeling for any movement that does not transfer efficiently to the next component. I emphasize using your eyes AND YOUR HANDS as some movement can be better felt than seen. Also, leave the bus on the ground for these tests with front tires straight ahead.
First, there is the steering wheel and associated column. Not much can go wrong with these, but they attach to the underlying steering box via a rubber square, aka steering coupling disc, located right under the bus floor. Have a friend turn the steering wheel, not enough to turn the wheels but just past the point where resistance is met, while you crawl under the bus to watch the rubber square. The coupling should not bend/flex when the steering wheel is turned and should not have any cracks in the rubber. If it flexes or bends with the steering wheel, is fractured, or you have doubts, replace it; they are pretty inexpensive – just research for the better manufacturers. Moby’s steering coupling is in very good shape (see photo below) as I saw and felt no movement at this junction.
Below this junction is, as previously mentioned, the steering box (see above picture). These boxes come in two versions for bay windows. ’68 through ’72 used worm and peg boxes which are NLA new and must be rebuilt if possible. After ’72, VW switched to a worm and roller box, which are supposedly not re-buildable but are available new. Moby is a ’71 so all future discussion of the steering box will refer to the former, early box. At this point, we are just looking for free play, and as your friend turns the steering wheel back and forth once more, follow the movement of the coupling and see if it translates through the box to the peg shaft (pitman shaft; see picture below). What you are looking for is any delay in the motion of the peg shaft, i.e., does the coupling move a lot before the peg shaft begins to move. It may help to put your hand on the drop arm (attached to the peg shaft) so you can feel when movement begins.
If you find play in the box, it might be time for an adjustment (see Bentley manual) or a rebuild, but before charging out and pulling the box, check the rest of the components first. Once more, I did not find anything amiss at this point in Moby’s steering.
Attached to the drop arm (also known as a pitman arm), you’ll find the drag link which transfers movement from the drop arm to the relay lever mounted on the axle beam. Check for play by watching the drag link connections as the steering wheel is moved. The drag link should move at the same time the drop arm moves and transfer the motion to the relay lever, which in turn should start moving when the drag link does. Make sure the drop arm does not move before the drag link and that the drag link does not move prior to the relay lever. All three constituents should move in unison. This was not the case for Moby as the drag link connections moved about 0.25-inches away from both the drop arm and relay lever before transferring any steering motion. I seemed to have found a problem but the rest of the workings also needed to be checked as any steering wheel play is intensified by worn or improperly installed/adjusted parts along the entire system.
Next, follow the relay lever to where it connects with the tie rods and from there look at the tie rod-torsion arm junctions; ball joints and steering knuckle making sure all the parts transferred motion efficiently down the line. After this, check the condition of the steering damper and proceed to inspect the wheel bearings, accomplished by grabbing the front wheels and pushing and pulling (perpendicular to the bus); the front wheels must be off the ground for this test. Any free play found should be noted along with the associated parts as these will need adjusting in the very least or complete replacement. In Moby’s case, the drag link was the sole culprit for my steering woes.
Replacing the drag link was a first for me, but I have heard many drag link horror stories. The link is pressed into both the drop arm and relay lever. These junctions can bind tightly leading to a lot of potential energy in the puller and the possible use of a BFH; though I hoped to avoid hitting the drag link as it can damage the connecting parts. Some recounted bloody stories of the puller slipping off and flying into one’s forehead, while others tell of a sudden release of the drag link throwing tools everywhere. Hopefully, I amassed some tips here that might help some avoid such situations. All in all, the process went a lot faster and with less fuss than expected; taking perhaps about an hour and half including centering the steering box.
Let me just add that this replacement has completely changed the experience of driving this bus. The Mother’s Day trip up and down winding mountain roads on what turned out to be a pretty windy day would have required a lot more work with the old drag link. I should have done this long ago!