The weakest link (new draglink)

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.

Steering box and rubber steering coupling as seen under the bus.

Steering box and rubber steering coupling as seen under the bus.

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.

'68-'72 steering box. Peg shaft is located on the right side in the above image. Drop arm is attached to peg shaft.

A spare ’68-’72 steering box I picked up in a junkyard in case Moby’s turned out to be kaput. Peg shaft is located on the right side. Drop arm is attached to peg shaft.

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.

Drop arm connected with the drag link.

Drop arm connected with the drag link (with a fair amount of paint overspray). The drag link pictured moved about 0.25 inches horizontally away from the drop arm before moving toward the rear of the bus – not a good thing!

Drag link connecting to the relay lever.

Drag link connected to the relay lever.  In addition to the extra movement at the drop arm, the drag link moved up (vertically) about 0.25 inches before the relay lever moved.  This extra movement amplified the free play at the drop arm.

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.

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Before removing any part of the steering system, park the bus with the front wheels pointed straight ahead. This is fairly simple as you just drive the bus in a straight line and park it on a level surface. Then straighten the little cotter pin nestled in the castellated nut (see picture above).

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The cotter pin was too small for the tip of needle-nose pliers so I used an awl to pry it out. After removing the front cotter pin, remove the back one located at the drag link/relay lever junction.

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Now remove the castellated nut using a 19 mm socket/box wrench. Surprisingly simple as these nuts are only torqued to 22 ft lbs (3.0 mkg). Don’t forget to do the rear.

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There are many types of pullers out there and most seem to be adequate for this job. Check your FLAPS.

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Ironically, the idea here is to push the drag link out by centering the puller screw shaft on the drag link bolt and positioning the puller to grab the drop arm. Before I attached the puller, I put the castellated nut back on the drag link bolt so the bolt was just a few threads shy of becoming even with the top of the nut. This will prevent (hopefully) any parts from flying around when the link pops out of place.  You may also want to wrap the puller in a towel in case it lets go of the drop arm; your forehead will thank you.

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After researching a bit, I expected to need my breaker bar to apply enough torque to pop Moby’s 40 year-old drag link.  A friend recommended applying a fair amount of torque on the puller screw shaft and then hitting the link with a hammer to get it to let go.   Using only the socket wrench, I got it pretty snug.  Figuring I’d go one more turn before getting the breaker bar and really baring down on the puller, I was very surprised when the link popped after 1/4 of a turn.  It really didn’t require that much effort after all, and the castellated nut kept everything in good order.

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Drag link popped from the drop arm with only the castellated nut holding it in place.

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After removing the nut, the link came out easily.

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The rubber seal around the joint boot also came out easily (FYI: removal of this seal is not necessary and was completely unintentional).

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Next came the rear joint. Again, I screwed the castellated nut so it was not quite even with the drag link bolt and then attached the puller.

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No need for the breaker bar here either.

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The new drag link. Several brands have a good reputation, including this one which came from a respected, local parts dealer. Everyone always makes such a big deal about parts made in Germany as being some of the best, and rightly so, but I had to chuckle because while the box had “Germany” all over it, the tiny sticker on one end said “made in Turkey”.

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Old link (top) and new one (bottom)

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The two differences I noticed immediately between old and new were the longer joint bolts and simplified nut which locks the length adjustment.

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The old joints were very easy to work while the new were very stiff. In fact, the new joints held their position after I let go but the old ones…

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…did not.

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Before I installed the new link, I wanted to double check if the steering box was truly centered. Why? Because it is easiest to do when the drag link is off and a non-centered box wears prematurely. I picked this method up from Desertbusman on The Samba; it is posted on just about every drag link thread I saw, but the Bentley manual goes through the centering process as well.  To start, turn the steering wheel so the bar is parallel with the front of the bus. Stick some tape to the dash at 12 o’clock and run it straight back so it intersects the wheel at 12 o’clock as well.  If you own a bus with a steering wheel lock, insert your key or you will have a lot of trouble turning the wheel (seriously, there is an entire forum thread out there trying to resolve an immobile steering wheel post drag link replacement.  Turned out the guy forgot about the steering wheel lock).

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Cut the tape between the dash and steering wheel. Now you can keep track of the wheel’s position through the centering process.

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Slowly turn the wheel around to one side and then the other. Somewhere, hopefully where the wheel tape aligns with the dash tape, there will be a spot with slight resistance for, perhaps, 2 or 3 inches worth of turning. Once you encounter the resistance, keep turning the wheel back on forth through the spot to get an idea of its size. When the steering wheel is in the middle of the resistance, the steering box is centered. Do not pay attention to the steering wheel bar! If it is no longer parallel with the front of the bus, it is OK for now. In the above photo, the steering wheel has just met resistance when turning to the left. The tape almost lined up perfectly when the wheel went through the the middle portion of drag, so I did not make any changes to the steering box.  If the spot is not found, adjustments can be made easily to the steering box to bring it back or lessen the resistance if too high; check the Bentley manual.  After centering the steering box, tape a new 12 o’clock position (remove the old tape) on the steering wheel.  Now gently turn it all the way to the left until it stops.  The tape mark should be around  8 o’clock.  Now turn the wheel all the way to the right until it stops.  The tape mark should be at 4 o’clock.  Return the wheel so the tape is back at 12 o’clock and aligns with the dash tape; tape or tie off the steering wheel so it does not move.  If the center bar is no longer parallel with the front of the bus, the steering wheel needs to be removed and put back so the bar is correctly oriented.  Do this AFTER replacing any/all steering components and AFTER having a front-end alignment done.  Popping the steering wheel off is pretty straightforward but be VERY careful not to crack the steering wheel plastic.

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Time to adjust the length of the drag link. Simply turn the joint on the threaded end (right in the photo above) to lengthen or shorten the link. I made mine the same length as the old one as a start and then hand tightened the nut to keep the length from inadvertently changing during installation. Place the the rear end (left above) in the relay lever, and the front (right above) in the drop arm. The length may need further adjusting to get the bolt in the drop arm (mine needed another turn to increase length).  Then tighten the length control nut enough so that it doesn’t come loose (it doesn’t have to be ultra tight as the length can’t change after installation).

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New drag links come with nylock nuts instead of castellated ones.  The new link bolts do not have holes for the cotter pins.

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The nylock nuts can pose problems during installation as the increased resistance of the nylon bushing may cause the drag link bolts to turn within the joint before they can seat themselves in the drop arm/relay lever. While the castellated nuts cannot be reused for the final installation, I did find them handy in getting the bolts seated in the drop arm/relay lever sockets. Once partially seated, the bolts no longer turn and the nylock nuts may be used for final torquing.

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The original specifications call for 22 ft lbs (3.0 mkg) of torque on the link nuts however, the nylock nuts are a tad different.  The torque values change because the nut has a higher turning resistance due the nylon bushing.  The torque required to turn these nuts should be added to the original torque value.  In this case, I found it took approximately 5 ft lbs to turn the nylock nuts (before it came into contact with the drop arm), so I used a final torque of 27 ft lbs.  I have no idea if it makes a difference, but what the heck.

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After the drop arm comes the relay lever (I have no idea if it matters which is done first). This bolt proved more difficult as it turned even with the old nut, which of course kept the nut from tightening. I had to reach up with one hand, and pull down on the drag link while at the same time turning the socket wrench with the other hand to tighten the nut. The weight of my body was enough to just seat the bolt in the relay lever and keep it from turning; the castellated nut did the rest, and the nylock nut went on without a hitch.

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She sure is purty! A turn of the steering wheel indicated that the steering was much improved, and I knew as soon as I backed Moby out of the garage that it was correct. After a quick test drive, I buttoned up the pedal pan and went back to work on the interior.

 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!

3 thoughts on “The weakest link (new draglink)

    • Glad it helped Jesse! The switch should be a fairly simple project as long as the old drag link isn’t rusted in place. Before you take out the old, make sure there isn’t any play in the rest of the system. If there is, it’s a big time saver to replace all the worn components at once. Good luck with your project and thanks for taking the time to leave a comment.

  1. Pingback: New Front Axle, Part II | Campervan Crazy

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