Results 1 to 9 of 9

Thread: E46 Subframe Issues

  1. #1

    Default E46 Subframe Issues

    Hi,

    I'm currently looking at a clean M3 for sale, but worried about subframe issues. Are they common on a E46?

    Where in the Montreal area could I get it reinforced and checked? How much $$ are we looking at?

    Thanks

  2. #2
    BMW Club hamadyr's Avatar
    Join Date
    Feb 2006
    Location
    Montreal
    Age
    50
    Posts
    241

    Default

    You did not mention the year of the car you are looking at or its mileage. That being said, a comprehensive pre-purchase inspection by a competent specialist is the cheapest form of insurance available on the market today. In this case, it means someone who knows the particular make and model vehicle intimately.

    That being said, a quick internet search will show that the subframe mounting point failure on the E46 chassis is not an urban legend. BMW settled a class action in the US by inspecting and repairing unmodified vehicles. Factory approved repairs range from the injection of Epoxy Foam to the complete replacement of the rear floor. Naturally, the aftermarket has also come to the rescue with repair and reinforcement kits.

    Failures are common on early cars and diminish as bushing and eventually floor design evolved. The tipping point seems to be the LCI in 2002/2003 as failures seem to few and far between after that point. The more aggressive the driver, the more probable the failure…

    There are many competent shops in the Montreal area with the ability to diagnose and repair this issue.
    My personal favorites are:
    - WeTune : http://www.wetune.ca/
    - TC Automotive: http://www.tcautomotive.ca/

    Keep in mind that this is not an inexpensive repair if you want it done correctly.

  3. #3

    Default

    It's a 2003 with 120k km's. Apparently there are no cracks but I would like to get it done before it does and wonder how much it would be at a reputable shop.

  4. #4
    BMW Club hamadyr's Avatar
    Join Date
    Feb 2006
    Location
    Montreal
    Age
    50
    Posts
    241

    Default

    On a 2003 which has been shown mechanical sympathy, you may be right. Still, there is no substitute for a thorough PPI.

  5. #5
    Hiding in the bushes Gregster's Avatar
    Join Date
    Feb 2006
    Location
    Pointe Claire QC
    Posts
    2,795

    Default

    Quote Originally Posted by EspritV8 View Post
    It's a 2003 with 120k km's. Apparently there are no cracks but I would like to get it done before it does and wonder how much it would be at a reputable shop.
    They all crack! Some are worse than others but for the most part the cracks are small and often hard to see (hidden by the bushings). To see them properly requires removal of the rear subframe, grinding of the undercoating/paint then grinding out of the crack, drilling at both ends, welding, grinding the weld and putting in the plates. Did I mention more welding?

    There is simply too much "slop" in the subframe bushings that puts load on the mounting points. Whenever I do a reinforcement I install delrin subframe bushings or even aluminum (I have these in my car) slight increase in noise/harshness but you will never have to change them again and the "slop" feeling in the driveline is removed. Labor wise is around 10 hours plus parts, I suggest to clients to also have the trailing arm bushings changed as well. I'd also plan for replacement or rebuild of the VANOS unit on S54 if it hasn't been done already. Dr.Vano's sells them for a decent price

    This is a job I do fairly often and I actually consider it part of normal maintence. If you wish to discuss options I can be reached at 514-835-1728

  6. #6

    Default

    Thanks for the details. I thought vanos on the M3 was more reliable than other models... I'm guessing this also costs an arm and a leg??

  7. #7
    Hiding in the bushes Gregster's Avatar
    Join Date
    Feb 2006
    Location
    Pointe Claire QC
    Posts
    2,795

    Default

    Quote Originally Posted by EspritV8 View Post
    Thanks for the details. I thought vanos on the M3 was more reliable than other models... I'm guessing this also costs an arm and a leg??
    http://www.drvanos.com/index.php?opt...=blog&Itemid=6

    I'd also like to add the crank damper failure.. You'll need to stay up to date on valve adjustments as well.

  8. #8

    Default

    Thanks Greg for all the input. I've been looking for awhile now to get a decent manual E46. They all seem pretty overpriced, and the ones with the SMG are way more affordable. What do you think about the SMG? Garbage? Easy to convert to manual if I get bored? Cheap conversion or way to expensive to even consider it?

  9. #9
    Hiding in the bushes Gregster's Avatar
    Join Date
    Feb 2006
    Location
    Pointe Claire QC
    Posts
    2,795

    Default

    Quote Originally Posted by EspritV8 View Post
    Thanks Greg for all the input. I've been looking for awhile now to get a decent manual E46. They all seem pretty overpriced, and the ones with the SMG are way more affordable. What do you think about the SMG? Garbage? Easy to convert to manual if I get bored? Cheap conversion or way to expensive to even consider it?
    SMG itself is crap, I believe new E46 SMG pumps/actuators are no longer available. The conversion isn't cheap but it's not that expensive. It's the same transmission. You need to weld in a new mount, change the bell housing and a bunch of other little small parts. Here is a decent write up http://thegarage.jalopnik.com/how-to...t-t-1747802451

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •