Steering Gear Adjustment

[leathermaneod]

Hey guys, 

Most of you know that I recently did A LOT of work on my power steering system, including attempting to rebuild the gear box, which failed forcing me to replace it with a reman. Anyway my trucks steering has never been what I would call very bad, but it's always had the usual 10-2 dead spot. The new box and shaft and even Rock Solid Ram Steering Fix bushing did nothing to help that, though the bushing did get rid of the clunking. I am also guilty of sanding the bushing a little too much to prevent binding in cold weather and so I still have a little movement in the shaft. Anyway I got tired of the dead spot and read up on the "over center adjustment". I tightened the screw about 1/8-1/4 turn max. It helped some but I still had a dead spot. After some more research I found quite a bit of emphasis on performing the bearing preload adjustment BEFORE the over center adjustment. Anyway I ordered a spanner wrench and finally performed the bearing preload adjustment after returning the over center to the way it was. Now I was able to turn the nut about 1/4 turn max before it got tight. So I backed it off about 1/8 turn to halve the total movement. It definitely reduced the dead zone and the steering still feels fine. My question is, do I tighten up on the preload more even though there's only about 1/8 turn left? Or do I now adjust the over center? 

[Wild and Free]

You still have the OEM intermediate steer shaft between the steer column and gear box? If so there is some flex in the coupler in the stock shaft.

Also you Do have a 3rd gen trac bar with poly bushings? If not there is another spot that will cause play.

Edited July 27, 2016 by Wild and Free

[leathermaneod]

I replaced it, but it is a stock one from rock auto. I know what you mean about the play though, this new one has it already. Very disappointed with it.

[leathermaneod]

Anymore input on this guys?

[TFaoro]

If we could find a book that would help. I'm sure the pre-load is supposed to be a set torque.

[leathermaneod]

You are correct, it is supposed to be torque set, that can be found in the FSM. However, I don't have a torque wrench adapter for a spanner wrench. Plus the plug has way to much resistance to be torqued accurately. 

[TFaoro]

Sounds like it's time to guess.... I wouldn't crank it down, but I would make sure it's snug, then adjust the OTC until it gets stiff, then back it off until it steers properly.

[leathermaneod]

Sounds like a plan! That's kinda what I was thinking after feeling it out, but I wanted a second opinion. Thanks!

[Mopar1973Man]

Most play is in the over-center adjustment. The bearing pre-load typically isn't the source of the loose steering. Don't get me work it can but very rare. 

[leathermaneod]

What's the most you would turn the over the center adjuster? Ive also come to the conclusion that my track bar is on it's way out as I can move the upper joint some by hand. 

[Mopar1973Man]

Like my last adjustment, I bottomed it out then backed off 1 full turn. To get bottom you might have to jack front axle up and and rock the steering a bit. The adjust again. Once bottom is found then you got to set in some slack. One member said 1.5 turn back mine is goodf at 1 full turn back. So start with 1 full turn back and might have to go 2 full turns back at the most. I did try the fully bottom out adjustment its stiff and won't center very well. 

[leathermaneod]

Thanks for the great info! Everything I read so far, including the tsb, said not to tighten it more than a 1/2 turn total so I was kinda scared to go to much. I assume by bottoming it out you mean to tighten it as far as it will go correct?

[Mopar1973Man]

That's at least what I did. I would seat the pitman gear fully in the rack by tighten the adjustment as far as it would go easy. Then back the adjustment off set number of turns. Kind of like doing band adjustment on the 47RE transmission you torque the adjustment screw to 72 inch pounds then back off a set number of turns. This will provide the needed slack for the gear to move properly. Like I found out by setting it tight its very stiff and doesn't self center at all. What happen is the pitman arm gear binds up in the straight travel. 

 

As you can see in this picture that is exactly how the gear mesh. The "sector adjustment" as label in this picture is how much its pushing the gear into the "power piston" or the rack. 

 

As for the bearing pre-load that is how much force is applied from the input cap pushing against the bearing on the worm gear. 

Edited July 29, 2016 by Mopar1973Man

[leathermaneod]

Thanks for the detailed info! Here's another question, I'm starting to think my return to center isn't as good as it was before. If the wheel is pointed as far as about 10 or 2 it doesn't select center. It will come back to about 10 or 2, but not the rest of the way and I don't think it was like that before. Could I have caused that by tightening the bearing preload too much? I'm thinking maybe the preload was good but the over center needed more that what I tried? Could the preload being too tight cause weak return to center?

[Mopar1973Man]

Something is most likely too tight now. I would re-check what you have done then maybe back off just a bit. 

[leathermaneod]

Ok. Guess I'll try the over center first since that's easier. Then the preload if it doesn't help

[leathermaneod]

Alright so I've been fooling with this thing some more and I encountered something that seems odd to me. I set the preload back to approximately where it was and re adjuster the over center by tightening it till it wouldn't go anymore, then backing off half a turn since from newnit was backed off about 1 full turn. Well that was way too tight. Didn't return to center very well when it got close. So now I set it to 3/4 of a turn out from all the way in. Haven't driven it yet but when I tried to adjust it, I attempted to back it off more than a full turn and it would not go. It got just as tight loosening as it did tightening with only 1 full turn or so in between. Is that normal? Is it maybe because I did. It have the front end off the ground to remove the chance of binding?

[leathermaneod]

Another annoying thing I noticed now after driving my truck, I still have very poor return to center. Makes it really hard to go straight down the road. Every correction has to be re corrected the other way. I don't know if the preload is too tight still or what. Kinda confused :-/ Any advice is appreciated 

[Wild and Free]

Give Ryan @ Bluetop gears a call and he can walk you through it, His cell # is 701-301-1256. I will not touch steering gears anymore knowing more about what is inside and doing it correctly from visiting with him a few times about them, best left to the experts with the knowledge of doing it the proper way.

[leathermaneod]

I appreciate you giving me his number. I've got to get this figured out somehow lol. 

I appreciate you giving me his number. I've got to get this figured out somehow lol.