steering box E28

paulvdree · 21st July 2004, 02:05

I have not yet read about the subject of worn steering boxes here.
Some thoughts:

I have owned a few E28's. Although the steering box gear end play is adjustable (screw and lock nut), this doens't get good result because the sector and "rack" are always worn locally (not evenly), so the play can never be eliminated thoughout the entire range of motion. New steering boxes are very expensive and used ones all have the same problem.

I was pleased to find that the manual from Schiff European covers steering box overhaul in detail, making the job much easier. I also have the required knowlegde, experience and contacts to have the sector and rack reground and hardened, which would get them into "as new" condition. However, this is very expensive for just one set of gears, so I would like to do 5 or 10 sets at least. This might result in a realistic overall price.

Would anyone be interested, or any other ideas or leads?

p.s. I drive a euro E28 M5. According to the ETK this is the only E28 model with a different steering box (same as M635Csi). Does anyone know what the difference is? It looks the same as any other. Fast ratio gears maybe?

Regards, Paul

de Witt · 21st July 2004, 06:12

Hi,

The steering ratio is 15.1:1. Cant really compare much to any other E28 model as I havent driven any other than the M5.

I cannot comment on rebuilding the steering box. When that time comes I have plans for a rebuild with a fellow in town who discussed the E24 M6 box and said his was loose and needed a rebuild.

I have a massive steel dowel that was CNC'ed for me when the steering box breaks off of the subframe. Eventually this will happen, not in the next 50k miles I dont suppose. I will mount the dowel through the subframe and through the steeringbox. I can snap a few pics of this if you would like.

paulvdree · 22nd July 2004, 02:06

I will try to find out what the ratio is for the regular BMW's.

A sloppy steering box can ofcourse be caused by other factors than gear end play, like worn or misadjusted bearings, but I'd say that in any old steering box 80% of the play will be caused by the "gears". So when you have it rebuilt, make sure that the "gears" are remachined or replaced. By the way, to my knowledge BMW does not deliver steering box parts seperately. The steering box must also be adjusted properly. Too tight or too loose will both result in accelerated wear and bad performance.

I'd really like to see a picture of this steel dowel. How is the steering box supposed to break off the subframe? Rust? Fatigue? Or is this something that is only needed when the car is raced?

Greetings, Paul