Of all the woes that an E53 can bring into your life, I would consider the rear air suspension to be the least woeful. I replaced both rear bags immediately after getting mine because one blew on the transport from CO to TX. The pair cost me under $300 and took about 4 pretty easygoing hours to swap. That said I have pretty skewed view because now that I've done the timing guides on my m62 I fear not even fear itself, except maybe doing any work in the driveway in the middle of summer, I do fear that.

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Again Daily Driven SC'd 4.6iS, whats the point of having a sweet ride if you dont use it all the time.