Steering Box Adjustment

[Peter C. King]

I’ve seen a couple of threads that commented on sloppy steering, but nothing on adjusting the steering box.

How much freeplay do you have in your steering wheel? That’s how far the steering wheel moves from side to side before the wheels move. It feels like a dead spot. If it’s big enough, i.e. more than one inch, you wind up chasing the front end, particularly at speed. 

Nowadays you can’t even find what passes for a steering box on modern cars. Back in the day it was a box of gears that translated the rotational motion of the steering column into left-right motion at the wheels.

It’s easy to find. Follow the steering column toward the front of the car until you find a box. On top of the box is a large stop nut surrounding a set screw with a slot in it. Above that on the box cover is a 4 sided bolt. Take out the bolt. The box should be full of 90 wt gear oil. If it isn’t, fill it up. Install the bolt.

Next, Swing the wheel from side to side until you have a feel for the dead space. One inch? You’re good. Congrats on lubing the steering box. Three inches? Keep reading. Back off the nut. It’s there to hold the set screw in place and maintain constant gear lash, just as the stop nut on a valve adjuster holds it in place to maintain valve lash. Tighten the set screw the width of the slot and swing the steering wheel again. Is the dead spot smaller? Repeat until the dead spot is almost gone. An inch will do. Hold the set screw in position with the screwdriver while you tighten the jamb nut. Did the dead spot grow just a bit? The jamb nut does that to valve adjusters too.

Do not crank the set screw down until it stops. The gears will gall and fail if there is no freeplay between them. Road test the car and see how the steering feels. It should be smooth with a little freeplay. The gears are too tight if the steering has a lumpy feel. Back up the set screw in that case.

What if you screw the set screw in as far as it will go and there is still too much free play? You need an internal shim adjustment. The dealer was the only source for that fix once upon a time. I doubt that today’s VW shop would even know what you were talking about. You need a new steering box. Or, you could take the box apart and play with different thickness shims. You’re trashing the box anyway.  

You will be amazed at how much better your TD drives with tighter steering. It goes where you point it. Four wheel drifts become commonplace, even if they are only in your mind. Goggles and a leather driving helmet will appear on your Christmas list.

Sweet.

Then there’s the story you tell when someone is bragging about his big block tire melter. Anybody can bolt on a set of headers. But when’s the last time you adjusted your steering lash?

Priceless.

PMOSSBERG40711.5258101852

[Paul Mossberg]

BDriver,

Thanks! This is a great article!

Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica Roadster

If you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)

[newkitman]

Here’s a link from a VW site that explains how to adjust the steering box. In fact, there are a number of good procedures there.

www.vw-resource.com/steering_box_adjustment.html

Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The Shack

[Dennis Brock]

Wonderfully written and explained.  When I started, I had almost 1/4 turn of slop.  Adjusted the steering box and took most of it out, but still had too much.  Don’t forget the steering coupler!  That’s how I got most of the rest out of it.  If there is wear, tearing, or loose fasteners, it can be real sloppy, not to mention dangerous.  Less than $10 and available in stock or urethane.  If you need a new steering box, try hard to find a German one. IMHO a rebuilt German is better than a new Brazilian, and definately better than a Mexican box.

[edward ericson]

Word on the steering couplers is that the pretty red urethane ones fail; stick with rubber.

[Paul Mossberg]

I agree.

Those German engineers used rubber.
That should be good enough for us!

Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica Roadster

If you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)

[Author]

Posts