Steering Box Removal - Tips, DIY Guide?

[racer2086]

Hey all,

Does anyone have guidance on how to remove the steering box? Is it hard? I'm going to be replacing the suspension pieces anyway, so figured now is a good time.

Now that the transmission is fixed, I'm going to completely replace the front end (mechanic said thrust bushings are bad (only 2 years old), steering box has play, center link and idler have play). I figure now is the best time to send the box out to get reman'd. I found a place in AZ from the M5 forum that rebuilds these boxes for less than a reman unit. That name supposedly was alluded to in discussions between a member and a ZF employee.

I'm going to start on this project tomorrow so any advice is appreciated.

[KinkedChrome]

Edit: I'm an idiot, the steering box can come out without the subframe dropping.

For the steering box to come out, your going to need to drop the subframe. I guess you could pull the engine instead. Best bet is too probably rig up something so you can suspend the engine from the strut towers. Unless you have a hoist that won't get in the way of dropping the subframe while supporting the engine.

[racer2086]

Oh no...I have to drop the subframe? I glanced at the BMW instructions and it didn't notice that, but I was skimming. I was hoping to find some pictures etc, so I'll know what I'm working with once I get under there.

[Trasportador]

Far easier to drop the subframe, and undo the steering joint fastener. Will also need to drop the trans bracket to get enough downward movement of the entire drivetrain.

[racer2086]

Re-read the TIS instructions. It just says to remove the steering wheel. (Why?)

Then it says remove the two hydraulic lines, remove the pitman arm, slide the steering shaft off after loosening the bolt, disconnect the servotronic, and un-bolt the 3 bolts holding the box in. That's it. Could it be that simple? If I have to drop the subframe/transmission, I'm not going to do it. And I don't want to try half way and get stuck.

[KinkedChrome]

Re-read the TIS instructions. It just says to remove the steering wheel. (Why?)

Then it says remove the two hydraulic lines, remove the pitman arm, slide the steering shaft off after loosening the bolt, disconnect the servotronic, and un-bolt the 3 bolts holding the box in. That's it. Could it be that simple? If I have to drop the subframe/transmission, I'm not going to do it. And I don't want to try half way and get stuck.

That's all you have to do to unbolt it from the subframe, but I don't see how it would be possible to remove and replace without pulling the engine or dropping the subframe. It's only 6 bolts to drop the subframe if you have the rest of the suspension already removed.

[CPHES]

yeah, there is a bit of work to get to that box. you will need to support the engine from the top, if you remove the subframe. Just doing the Center Link ( German TRW ), and tie rods ( Lemforder ) made a Huge difference / 156K on a 2000 750iL. that would also be the time to get a 22mm sport front swaybar in.

[clarkitect]

I looked at the TIS and it seemed rather generic for any BMW rather than E38 specific. I’ve never done the job but for what it’s worth the Bentley doesn’t mention dropping the subframe. Bentley isn’t always right on though. There is a special tool called out for adjusting the pitman arm.

Do you have a little play side to side when standing still?

[chris33]

I did it, took about thirty minutes. No need to drop the subframe.

[KinkedChrome]

I did it, took about thirty minutes. No need to drop the subframe.

Well know I feel like an idiot. Did you just pull it out the top and sneak it by the engine?

[racer2086]

Yes, there is notable play in the box. When the shop replaced my transmission, they test drove the car and told me the wear in the box was significant, whereas the play in the center link and idler arm was minimal in comparison. There is definitely play in the center of the steering. I can wobble the wheel back and forth like an inch going straight and the car will have minimal to no response.

The shop quoted me $1200 to replace the box with a reman, which at the time I passed on since I was tapped out from the transmission and figured I could drop it myself and deal with the box.

I have the suspension parts on order, so I'll get under it this weekend and look at the clearance. Maybe I'll just make an adjustment to the screw on the box? What would you all do? Box is not leaking or anything, I was just hoping to get it reworked and recalibrated.

[rslifkin]

I'd definitely try an adjustment to see what you can get without causing it to bind further out in the steering travel. Depending on how worn it is you might not be able to help much, but you can probably at least reduce the play a bit while you figure out replacement plans.

[CPHES]

Keep the adjustment on the light side. It also should be filled with oil. I’d do no more than 1/2 turn, test drive, etc.

[CPHES]

https://www.bimmerforums.com/forum/s...#post_16794559 - look at all of this tread

[chris33]

No, the bottom.

[racer2086]

Is it worth trying the adjustment or just let the rebuilder mess with it. They will replace all seals and bearings, but hard parts are what they are. They do machine things, so they may be able to machine certain parameters in order to be able to adjust it better.

I'm just thinking the adjustment won't get me there without causing binding and if there are bearings that are worn, it could be contributing to the slop. Whenever I go over bumps at low speed, there is a rattle from the steering box that migrates up the column. I could see that being a bearing issue that is allowing movement of a shaft that should otherwise be held firm. Thoughts?

[clarkitect]

Hell I'd try the adjustment before going through all the effort to replace it. If it's worn out and the adjustment doesn't help, you haven't spent a dime.

[rslifkin]

Hell I'd try the adjustment before going through all the effort to replace it. If it's worn out and the adjustment doesn't help, you haven't spent a dime.

My thoughts exactly.

[racer2086]

I just pulled the box. It was way easier than I thought once I pulled the pitman arm off. I wasted 30-40 minutes trying to finagle it out with the pitman arm on because I didn't have a puller that could fit in between the box and the pitman arm. But as soon as I loosened the bolt, the arm slid right off. You definitely need a combination of sockets, u-joints, and extensions to get the hydraulic lines loose and to get the most forward bolt holding the box to the subframe due to clearance.

There is next to no space to get to the adjustment screw with the box in the car. Plus, then I'm adjusting and readjusting and have no idea what is too much or too little. And I don't want to replace my suspension components with new until I'm done with the box, which means, I'm adjusting with old arms and ball joints in place.

The biggest issue I see is that the wiring for the servotronic is all cracked up right where it enters the solenoid. I either have to get creative with sealing it up or get another one. New ones are exorbitantly priced. Not sure where to get a used one other than get lucky in a junkyard.

[red740is]

Use "liquid electrical tape" on the cracked wiring.. does a great job at sealing things up while remaining flexible. I used it on my cracked headlamp wiring.. worked great.

[racer2086]

I've used that stuff before. It's great. In this case, I cut away some of the outer insulation, cleaned up the wiring, and injected E6000 glue in between the wires and all around outside, making a sealed unit out of that cracked wiring. Glue is flexible when dry, so that's nice. Just don't know how the glue will hold up (anything for that matter) with all that heat down there.

Box should be arriving at the shop tomorrow.

[rslifkin]

E6000 holds up pretty well as long as it's not in direct sun. UV will harden it and kill it, although I think there is a UV stable version out there.

[racer2086]

Well, I've been taking my time with this job for sure... Got the rebuilt box back weeks ago from Benchworks Steering in AZ. They turned it around in a little over a week. Great people to work with! It is my original unit based on the date code stamped on the plate on the box. It was cleaned and painted silver, instead of the factory black. No big deal -- looks clean!

I chatted with them on the phone after they had the box for 4-5 days. I actually spoke to the guy who was rebuilding it (you can talk to the guy working on your unit). They do not replace major hard parts inside (can't get them) other than races and bearings, seals, and the valve assembly inside. They had to order a valve assembly for mine.

I asked him about the adjustment on the box that is always referenced on this forum and if that could be used to eliminate any remaining play in the box. The way the guy explained it, that adjustment shouldn't be messed with and is like putting a "bandaid on a flesh wound." He said just replacing the bearings and races should remove 50-100% of the play in the box unless there is something severely worn.

So far, I installed the box and got the center link and tie rods back on. I performed the leveling of the pitman arm on the steering box as per BMW's TIS procedure and checked it at least 3 times. It seems like a big deal to them, considering the tolerance is +/-1.2mm: https://www.newtis.info/tisv2/a/en/e...g-unit/2hXQ1yP

Instead of the BMW tool, I used a drift set up I rigged up using my dial indicator magnetic base arms and a punch. The rod from the magnetic base was the exact size that fit in the lower control arm bolt spot on the subframe:


What is interesting, is that when I removed the pitman arm it was almost all the way up to the steering box. Previously done that way by a shop who replaced my center link about 9 years ago, and probably did not do anything to set the pitman arm height.

I cleaned the lower steering column of about 1" of grease, replaced the driver's valve cover that was slowly leaking, and cleaned the heat shield and all the other stuff under there caked in grease from 20 years of slowly leaky valve cover gaskets and power steering hoses. Also replace the return and suction power steering hoses. I have not filled the system with fluid yet, but just wiggling the wheel back and forth in the car makes it plainly evident that the box is considerably tighter. Can't wait to get everything back together.

Next on the list is to change the upper and lower arms and passenger side valve cover gasket. Also to remove the rust on the sway bar and get it painted so hopefully it doesn't rust more. After that, I'll get it back on the wheels, drive it around the block, and let it settle for a couple days before torquing the bushings down and getting an alignment.

Here are some pics...sorry I stupidly didn't take any with the box out of the car.

You can see the pitman arm level in this one and all the nice clean new parts


Another shot from underneath. The tie rod ball joint is blocking the view of the servotronic. You can see the rusty sway bar in this shot. The bushings trapped dirt, sand, and salt from the short time in CT. Hate rusty states.


This is the steering column bolted back on the box. That whole piece with the U-joint was completely black and covered in grease. I had my wife wiggle the wheel back and forth to check for play, and I noticed that the subtle clunking noise I hear in the steering is the U-joint down there, which is unfortunately ungreaseable and unserviceable. A new lower steering column that comes with the U-joint is like $500. No thanks, there is not enough play in that to care about.