Rear trailing arms
Posted: Dec 02, 2006 2:30 AM
Sorry, this is long and annoying
I need to replace the right trailing arm, so I decided to replace both of them, with the late ("braced") model - fitted on car built after sep. 1986.
The late model is p/n 33321133393 (left) and 33321133394 (right) and it was used on post 09/1986 E28 535i, then on E34 535i, 530i, 540i, also on E32 735i, 730i, 740i.
All have the same bearing: p/n 33411134549 (42x80x42 mm).
Two big surprises, on my quest for trailing arms:
1. E34 M5 and E32 750i use different trailing arms (p/n 33321137837 and 33321137838). Same bearing, though. The only major difference from the other E34 and E32 models is the self leveling system.
For example, the p/n for the E28 M5 trailing arm is also different from the p/n of E28 535i arm, but I never heard of E28 M5 guys that they need to replace the trailing arms, when they drop the self leveling system for the conventional E28 rear suspension. Or do they?
Question 1: Do E34 M4 and E32 750i trailing arms fit E28 535i?
2. Low models of E28 (post 09/1986) and E34: 520i, 525i, 528i, etc, also use a different trailing arm: p/n 33322225949 (left) 33322225950 (right). Even more strange, they have a smaller bearing: p/n 33411123415 (37x74x45 mm). I suppose that this trailing arm has the same geometry, but it's cut internally to accommodate the smaller bearing.
Question 2: What would be the technical reason for BMW, to use a smaller bearing for low power models, with the expense of tackling the logistics of more parts?
I need to replace the right trailing arm, so I decided to replace both of them, with the late ("braced") model - fitted on car built after sep. 1986.
The late model is p/n 33321133393 (left) and 33321133394 (right) and it was used on post 09/1986 E28 535i, then on E34 535i, 530i, 540i, also on E32 735i, 730i, 740i.
All have the same bearing: p/n 33411134549 (42x80x42 mm).
Two big surprises, on my quest for trailing arms:
1. E34 M5 and E32 750i use different trailing arms (p/n 33321137837 and 33321137838). Same bearing, though. The only major difference from the other E34 and E32 models is the self leveling system.
For example, the p/n for the E28 M5 trailing arm is also different from the p/n of E28 535i arm, but I never heard of E28 M5 guys that they need to replace the trailing arms, when they drop the self leveling system for the conventional E28 rear suspension. Or do they?
Question 1: Do E34 M4 and E32 750i trailing arms fit E28 535i?
2. Low models of E28 (post 09/1986) and E34: 520i, 525i, 528i, etc, also use a different trailing arm: p/n 33322225949 (left) 33322225950 (right). Even more strange, they have a smaller bearing: p/n 33411123415 (37x74x45 mm). I suppose that this trailing arm has the same geometry, but it's cut internally to accommodate the smaller bearing.
Question 2: What would be the technical reason for BMW, to use a smaller bearing for low power models, with the expense of tackling the logistics of more parts?