willysmjeeps.com

Any comments on this device? Walck's sent me
an eMail on it. Apparently it screws into the steering
box and tightens up the steering mechanism.

Jim in Darkest Arkansas

I saw the E-mail too. I'm suspicious of a magic bullet
to cure a worn steering box..

I saw this thread on the CJ2A forum, posted by the inventor. I'm not connected in any way with this. Just passing it along in case it might have additional information you'd find useful.

http://www.thecj2apage.com/forums/steer ... 8027777778

It fixes any wear problem between the worm and sector that causes you to set the adjuster screw on the side of the steering box so it isn't too tight. Usually is then too loose in the middle. It does not take into account bushing, ball, kingpin, bellcrank, tie rod, knuckle bearing wear, only the worm/ sector. Worked great for me, my new worm/sector had a tight spot due to crappy machineing. Huge amount of work to find the new parts bad. Easier for me to put in the Tightsteer. I really like it. It essentially spring loads the sector to ride in the worm independant of the wear in that area. John

From an engineering perspective, it makes a lot of sense. Similar concepts are used to create anti-backlash nuts for leadscrews for use in applications where you don't want any backlash ("slop") when the leadscrew changes direction of rotation.

There are two different tightsteer sector shaft tensioners made. one use's 7/16" x 20 threads and one is 1/2" x 20 thread adjuster.
Walch's says the M38 is 1/2" threads.

My steering box must not be original or the housing access plate was changed because the threads are 7/16".
Good thing I checked. If I decide to order one. I won't be ordering the one with 1/2" x20 threads.

Cacti_Ken wrote:There are two different tightsteer sector shaft tensioners made. one use's 7/16" x 20 threads and one is 1/2" x 20 thread adjuster.
Walch's says the M38 is 1/2" threads.

My steering box must not be original or the housing access plate was changed because the threads are 7/16".
Good thing I checked. If I decide to order one. I won't be ordering the one with 1/2" x20 threads.

According to the M38 ORD 9, Walck's info is wrong. The screw and nut are called out on page 267 as 7/16"-20. So, you may very well have the correct steering box.
The manufacturer's info on the CJ2A page linked above says the larger size is used in pickups (probably not interchangeable with an M38 box).

Good job Jim thanks for checking.

I don't see the point of the tightsteer. The set screw on the steering gear has very little to do with how "tight" the steering is. Its purpose is to hold the sector shaft in the proper place to engage the worm. The wear pattern on the sector shaft that causes "loose steering" is when the cheeks of the prongs start to get flats worn on the sides. Pressing the sector into the worm won't cure that! That will only cause more wear on the worm gear. In any case, problems with "loose steering" and death wobble are often associated with other worn and defective parts in the steering system, king pin bearing pre-load, etc.

Perhaps I'm misinterpreting how it works, but it appears to me that it isn't really making it "tighter" (higher force), rather it makes the parts follow each other better by ensuring they are always in contact.

Probably would've helped if I was there when Dad pulled apart the steering box instead of trying to understand his descriptions over the phone.

The set screw on the outside of the steering gear is there to position the sector shaft against the worm with the correct alignment and tension. The worm has a high point at the mid-section to provide center feel. You are supposed to tighten the set screw until a "slight drag" is felt at the mid point of travel when turning the wheel from max left to max right. The tightsteer shoves the sector into the worm throughout the range of travel - not what the engineers had in mind when they designed the gear. I think all that is going to do is to increase wear on the worm and sector pins, especially on the end of the pins. I suppose if the end of the pins is worn down one could expect that the sides or cheeks of the pins might remain in contact with the worm and thus reduce slop or free movement but that isn't going to help for very long. Eventually the sector pins and the worm will be worn from higher than designed pressure forcing them together. The big issue here is that for some jeeps (CJ2A, 3A), you can buy replacement sector shafts, I've not seen anywhere where you can buy new worms. Try out the tightsteer if you wish, I think it is a poor band-aid at best.

The worm has a high point at the mid-section to provide center feel.

Are you sure the center of the worm is greater in diameter then the ends? If that were true the sector would always want to drift to the low side of the worm (left or right). I have always noticed that when you adjust the screw too tightly you have stiff but reasonable movement in the center but very heavy or impossible movement further from center. This indicates the center of the worn is a low point relative to the sector.

TM9-1804B in "Downloads", page 160.

Turn the Pitman arm shaft clockwise until it cannot be turned any farther,
counting the complete and part revolutions of the Pitman arm shaft;
then turn it counterclockwise, half the number of turns previously
made. This will center the Pitman arm shaft. Turn the Pitman arm
shaft adjusting screw (Z) until a slight drag on the Pitman arm shaft
can be felt at this point. Tighten the Pitman arm shaft adjusting
screw lock nut (Y).

What I call the sector shaft is called a pitman arm in the M38 manual - I think I got the term sector shaft from the civvy manual for the early CJ's which also has a good section on adjusting the steering gear. The slight drag in the middle of the range is from a slightly higher area on the worm. Of course, that is for a worm that is in good condition. If the worm is severly worn in the middle, yes, it will tend to bind the sector/pitman at the extreme left and right limits of motion if the sector/pitman is too "tight" in the middle. At that point, go buy a tightsteer cause that is the only thing that will allow the sector/pitman to float in and out to counter the wear on the worm. But I wouldn't start with such a device if the steering gear is in good shape and can be adjusted to spec as it is intended to be! Forcing the parts together will only cause more wear over time. If the jeep isn't driven much, that may not matter, time is relative - even a worn steering gear can function Ok if everything else is to spec. Ask me again in a few weeks because I'm about to tear into my M38A1's steering gear for a rebuild.

"...........A shaft worm groove for pitman shaft tapered studs is cut narrow in straight ahead driving position. This design permits close adjustment for normal straight ahead driving and provides for takeup of backlash at this point after wear occurs without causing a bind elsewhere. from TM 9-8015-2, pages 229-230

The tightsteer doesn't adjust anything other than backlash within the Ross. Since it's spring loaded (with a choice of spring strengths), the spring serves to "self-adjust" the backlash as wear occurs. Whether this spring-loading causes accelerated wear in an otherwise servicable and properly lubricated Ross gear is the question de jour. My SWAG would be that over a 20K to 30K mile maximum vintage military jeep driving life, it will NOT produce noticable, incremental wear. So on a part-time driver and parade participant, how often would you need to manually adjust the backlash in order to keep the Ross steering with a "barely perceptible drag" in the straight ahead driving position?

The answer to that last question would seem to be the time and effort (performing the adjustment) that the tightsteer would eliminate. Am I wrong?

Right! Parade or incremental use won't cause much wear if the steering gear is properly lubed and mantained. But I still don't see the advantage to putting more spring force against the sector to TIGHTen the STEERing. Doesn't really tighten the contact between the sector pin cheeks and the worm if the cheeks are badly worn (oval shaped). That is what can cause excessive free play in the steering wheel movement before the jeep's wheels start to turn and I suspect that is what concerns most jeep owners who have "loose steering". Lots of other parts and adjustments come into play, of course. And of course if the sector pins are worn, like in my jeeps, the oil seals are worn and leaking and lubrication becomes a challenge which also means in a poorly maintained jeep the steering gear will be driven dry which also means more wear...and a owner buys a tightsteer to fix the problem. Rather than rebuilding the gear with new or at least not worn out parts and adjusting to spec.