When I bought my coupe over 17 years ago I knew the right front strut was from a different BMW. It has a 48mm gland nut and the bracket to hold the brake hoses was on the wrong side of the strut. It also had 8mm safety bolts holding steering arm to bottom of strut and they should be m10. I replaced it over a year ago with a used strut with the correct bracket and m10 safety bolts but with a 50mm gland. I didn’t realize it at the time but it is an inch shorter from bottom of perch to bottom of strut housing, this caused tire wear on inside edge of tire.
Today I swapped in a known e9 m50 strut of the correct length (I compared it to Paul’s original 74) and it took only 90 minutes. I have done it enough times that I have learned what to remove and what not to remove. I now have the correct ride height on both sides but the biggest difference is spring perch lip to tip of spindle which is ~15.” The one I just removed was ~14.”
With our recent discussion on differences in struts, I just had to look in the e9 and e3 Orange books. My findings:
- All use m50 gland nuts, m48 used on e12/24
- Very early 2800CS, very early 2500/2800 used m8 safety bolts
- All e9, Bav 2.8 used m10 safety bolts
- All MY 74 Bav 3.0, S and Si also m10 but strut part number changes with new longer control arms which changes geometry.
The moral is there are many different strut housing and you need to measure spring perch lip to to tip of spindle which is 15.” The e9 used three different struts, the e3 used five different struts with only the very earliest being shared with very early 2800CS. This all means the strut cartridges were different as well.
On left the one that came on my coupe but 48mm gland nut, on the right correct 50mm gland nut but 1” too short, although total tube height is very similar.
Today I swapped in a known e9 m50 strut of the correct length (I compared it to Paul’s original 74) and it took only 90 minutes. I have done it enough times that I have learned what to remove and what not to remove. I now have the correct ride height on both sides but the biggest difference is spring perch lip to tip of spindle which is ~15.” The one I just removed was ~14.”
With our recent discussion on differences in struts, I just had to look in the e9 and e3 Orange books. My findings:
- All use m50 gland nuts, m48 used on e12/24
- Very early 2800CS, very early 2500/2800 used m8 safety bolts
- All e9, Bav 2.8 used m10 safety bolts
- All MY 74 Bav 3.0, S and Si also m10 but strut part number changes with new longer control arms which changes geometry.
The moral is there are many different strut housing and you need to measure spring perch lip to to tip of spindle which is 15.” The e9 used three different struts, the e3 used five different struts with only the very earliest being shared with very early 2800CS. This all means the strut cartridges were different as well.
On left the one that came on my coupe but 48mm gland nut, on the right correct 50mm gland nut but 1” too short, although total tube height is very similar.
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