Originally Posted by vinniechin
It took my shop 3 hours to do the diff bushings and he didn't have the tool. He used a "disposable" tool clamped on the end of the bushing and tapped/hammered the old one out.
If you are doing the subframe bushings at the same time he can drop the subframe and do the diff bushings out of the car I believe and the total job in and out would take probably 7-8 hours.
My shop did not use/make a jig to replace subframe or have the tool to remove the stock subframe bushing (used a drill/air hammer).
Malek has said that you must use a jig or frame machine to ensure that the subframe goes back in straight. He said there is enough play to put it together "off" center. I didn't do it this way and wonder if I have any issues.
My shop did say that it probably wasn't necessary since when putting the subframe back in place if you don't put it in straight the pins would push the bushings back out.
However, with that said, I tend to trust Malek more since he has more experience working on the car. I don't know if I have any ill effects from the install but the car seems to track and drive straight. I wonder if Malek could comment if I have anything to worry about due to the way it was installed. Thanks.
To drop the sub-frame out and do the job that way, it will take approximately 12 hours total as the car has to be aligned again as well.
It's definitely recommended that the frame go in indexed properly with respect to the front axle and laterally. However, if match marks are used before the frame is removed from the car (BMW does ensure the frame is perfectly positioned at the factory) then you can use this technique to get it back into the same position as before.
When my sub-frame, differential and mounts broke at 3,xxx miles, the dealer replaced the sub-frame, diff and miscellaneous components, however they attempted to align the car 3 times and failed each and every time. Not to my surprise, the frame was not indexed correctly and I had to end up doing it and all was well from then on out.