Has anyone ever removed the steering box from the car? I have a leak on the steering box (not coming from any of the power steering hoses). It appears to be coming from the lower joint assembly (see: RealOEM.COM * BMW E39 M5 STEER.COL.-LOWER JOINT ASSY )

the source of the leak is where the steering column's lower joint assembly connects to the steering box (see RealOEM.COM * BMW E39 M5 HYDRO STEERING BOX)

it appears to me that there's an plastic ring or cup that seals PS fluid (#7 or #4 in the first link). seems like one of those pieces are broken and would need to be replaced.

the question is...how do we replace that? do we have to take the steering column out? or can we drop the subframe to get to the steering box?

Thanks,
Ed

Ed,

Subframe gets dropped for access. Good luck finding a shop to rebuild.

I know of a shop that does some authorized OE steering rebuilds for ZF (the OE mfr for E39 M5 steering box). They occasionally have luck with one-off special OEM steering rebuilds, so they are well known by european classic car collectors. The problem is they will probably not know if the box is fixable until they tear it down and contact ZF to procure parts. The shaft seal you describe is very likely the same part as used on garden variety 540i box. The servotronic valve and hoses are very close to the input shaft seal (just under parts 4 and 7), so I question whether you could discern the leak source in that cramped spot. The primary difference between 540i and M5 box is a servotronic attachment to the input shaft for variable assist (also used on E38 7 series) and the gearset ratio. I have a used E39 M5 as-is steering box I'll sell for $400 if you want to buy it. It's strictly a potluck deal because I have no history. sorry, rick

ps: be aware that the subframe drop is a pain in the but and this exercise is done to upgrade swaybars. you should consider the opportunity to kill 2 birds.

 

rick - thanks for the response. so there's no way to simply replace the plastic-ring or cup in the lower joint assembly for a fix? I would HAVE to get a new steering box?

-Ed

 

The two parts you point out on realoem are not seals. They are external steering column parts and they are not causing the leak. The internal parts are not sold thru BMW.

Hopefully you read my reply. I offered ideas how you might try to repair or replace. I didn't mention buying a new box which costs around $2500.

 

I have the same problem as well. Want to know if the power steering gearbox is rebuildable. Any others w/ this issue/experience with a fix?

Here's a pic of the leaking area that Ed and I are having (behind the steering gearbox where the joint attaches into the gearbox):




Thx

Jeff

 

Thanks again for the very informative response. I had been discussing this issue with Jeff and didn't think it was an easy job. Do you know how much it the the ZF authorized OE steering rebuild costs?

I've check getbmw parts and they're looking for close to $1,500 for a remanufactured steering box. RealOEM.COM   BMW E39 M5 HYDRO STEERING BOX

part # 32132228854

 

Ok... Its I finally have some time to contribute. Pulling the box isn't very difficult and LSCMAN is right, the plastic is not a seal or your problem. YOu will need a new, rebuilt or used box which shouldn't be a problem as there are quite a few M5s being parted out in the for sale section and on ebay. As for the removal:

Get it lined up on the lift
Support the engine from the top
loosen the power steering lines on the steering box
Lift the car
Place two pole jacks under the sub frame
remove the 3 bolts on the steering box
Remove the 4 sub frame bolts remove the allen head on the steering connection on the box. It is keyed so do not worry.
Slowly lower the pole jacks until the sub frame is resting on the suspension
The box will be floating up there so be-careful. Just work it out of there.
Install the new box and your good...


Ryan

 

Thanks for the responses guys. I think I'm gonna go with a remanufactured unit to play it safe. Guess it's time for me to look for an aftermarket front-sway bar.

 

Oz and racer,

My wife is applying more pressure to liquidate spares lol. If you do not find an affordable rebuild option and decide to go used, to ease your mind I will offer you a 6 mo total satisfaction money back warranty on my "used M5 salvage box". As with any store bought item, the money back warranty applies to the part only, not any labor or shipping fees (either way).

Price has dropped too:

used E39 M5 box for $375
used E39 M5 P/S pump for $150

As I mentioned, it is a used part I bought as a race spare. I have no history and never tested it, but I do know the seller had a ton of used M5 parts including P/S pump etc. The car was parted out over 2 yrs ago when the E39 fleet was younger.

rick

 

Oz and racer,

My wife is applying more pressure to liquidate spares lol. If you do not find an affordable rebuild option and decide to go used, to ease your mind I will offer you a 6 mo total satisfaction money back warranty on my "used M5 salvage box". As with any store bought item, the money back warranty applies to the part only, not any labor or shipping fees (either way).

Price has dropped too:

used E39 M5 box for $375
used E39 M5 P/S pump for $150

As I mentioned, it is a used part I bought as a race spare. I have no history and never tested it, but I do know the seller had a ton of used M5 parts including P/S pump etc. The car was parted out over 2 yrs ago when the E39 fleet was younger.

rick

Lscman-
Thanks for the offer. I found another alternative or will go new/reman from the stealer. Based on what I have read on the Tis, the subframe doesn't need to be dropped. Man, I wish there is someone out there that can confirm this. Will keep everyone posted as I think I will attempt it w/o dropping the subframe per the Tis.

Jeff

 

Aftermarket swaybars (28mm front and oversize rear) are sold by Eibach and Dinan. A pr goes for around $350-$550.

Hint: the 540i Eibach bars fit M5 & folks have been installing them for 5+ yrs. They used to be painted blue and sold by ACS for about $700. The price is cheaper now because they are labeled Eibach and painted red.

http://cgi.ebay.com/ebaymotors/EIBA...m280312986539QQitemZ280312986539QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories Indonesia seller with 100% pos feedback, see high shipping fee....use caution!

http://cgi.ebay.com/ebaymotors/EIBA...QcmdZViewItemQQitemZ360087700639QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

http://www.beastpower.com/Merchant2...creen=PROD&Store_Code=BMI&Product_Code=AC-BE39-SUS-SB&Category_Code=acsswaybars

http://www.m5board.com/vbulletin/sa.../vbulletin/sale-wanted/122936-fs-e39-dinan-front-rear-sway-bars-new-so-cal.html

 

I already do confirm this.. You need to drop the subframe. If you do not drop the subframe you cannot remove the box.

 

OK, thanks. Didn't know if it made any difference re access to the bolts etc. since I don't have oem manifolds but the Supersprint.

Won't go through the trouble then and just have a shop finish up the job.

Jeff

 

I know you guys suggest swapping out the front sway bar while they are dropping the subframe. Is this mod really worth it? Makes that much of a difference? I have the complete Powerflex bushings kit but have never installed it. I take it this should be done at this time to save a little $$ on labor eventhough my bushings are not worn. BTW I have an 03' w/ 43k miles.

Thx

Jeff

 

Oversize swaybars do not make a large difference, but the handling gains are measureable with a stopwatch and real.

I would not change out to powerflex at all. That sort of modification is appropriate for a competition race car, not a street car. It will not help handling with street tires and springs. It will just increase harshness and degrade an otherwise world class car. Serious $100K sports cars with 2 seats do not have poly control arm bushings & there's a reason for that. Those bushings will not measureably improve handling over fresh OE or X5 bushings on any track.

 

Subscribe!