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Thread: Subframe mounts torque?

  1. #1
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    Subframe mounts torque?

    Anyone have the torque figures for the subframe mount studs/nut and rear subframe mount torque?

    Bentley doesn't seem to cover.

    Thanks guys!

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    Isnt it considered the "connecting link to rear axle subframe"? 94 ft lbs?

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    I didn't see that, lemme check again.

    I see that now, but not sure. And, what of the rear subframe mount bolt torque?
    Last edited by 5mall5nail5; 07-22-2012 at 09:36 PM. Reason: Automerged Doublepost

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    I was talking about the big bolt that comes through the subframe. Which other ones are you talking about?

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    The subframers themselves and the big bolt (definitively).

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    Use a 1/2 impact and tighten them. No problems. Thats what we used on all the subframes at the dealer.
    Last edited by EuroPartConnect; 07-22-2012 at 10:04 PM.

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    I tightened to 110ft lb on both the e34 and the e21. No issues here

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    Gimme a minuite and I'll try to look it up. PDF is loading

    Looks like it's not gonna load, I can get it tomorrow if you don't get it by then.

    I'm guessing in the neighborhood of 90n-m

    Edit again:

    Google gave this:
    http://tech.bentleypublishers.com/th...threadID=36394

    It's in the PDF, looks to be 120 n-m but like I said, I can double check at work tomorrow.
    Last edited by Aradaiel; 07-22-2012 at 10:56 PM. Reason: Automerged Doublepost
    e46 m3, some 740 sport shorts, F30h, LR3 and a 540it

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    Yeah its not clear - I don't see 120 nm i see 127 mentioned twice though

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    1/2" impact is a measurement? lol

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    Quote Originally Posted by milKt View Post
    1/2" impact is a measurement? lol
    Not like is an aluminum bolt or a head bolt. Just so its tight is all that counts. Believe me I was all about torquing everything to spec, even brake caliper mounts,etc.When I started the top master techs would look at me like are you seriously looking up torque specs for everything, you must be new. After 4yrs working at a bmw dealer you learn what needs to be torqued properly and what can be tightened by hand or impact.
    Last edited by EuroPartConnect; 07-22-2012 at 11:33 PM.

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    Yeah, I don't torque subframe bolts with a wrench. I use my torque sticks and a 1/2" impact. I've verified it with a torque wrench to be within 5nm.

    Some people want to do it by the book, you can't fault them for that.
    e46 m3, some 740 sport shorts, F30h, LR3 and a 540it

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    By "connecting link to rear axle subframe" is it referring to the dogbones (pitman arms) or the actual rear subframe mount points to the chassis? Kinda confusing..

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    Quote Originally Posted by Aradaiel View Post
    Yeah, I don't torque subframe bolts with a wrench. I use my torque sticks and a 1/2" impact. I've verified it with a torque wrench to be within 5nm.

    Some people want to do it by the book, you can't fault them for that.
    If you use a torque stick, what torque stick are you using?

    I don't like the "hit it with an impact gun" because I run my impact at 120 psi and it produces like 250 ft lb....

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    I torque everything. My mechanic type friends point and laugh and I do not care. It isn't about speed for me, since I am paying to do it instead of vice versa.

    :shrug
    Quote Originally Posted by Layne View Post
    I can't speculate on what would cause the POOP alarm, but I would recommend pulling over immediately.

    Specialization is for insects

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    I went through this a while back. Here's what I found back then:

    Rear mount to body - 33 lb-ft
    Subframe to rear mount - 57 lb-ft

    I used this resource: http://www.bmwtechinfo.com/repair/main/


    Drivertain: Getrag 260/6, E34 M5 clutch, 15 lb FW, E36 M3 shifter, Portland Driveline driveshaft
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    Quote Originally Posted by 3axap View Post
    I went through this a while back. Here's what I found back then:

    Rear mount to body - 33 lb-ft
    Subframe to rear mount - 57 lb-ft

    I used this resource: http://www.bmwtechinfo.com/repair/main/

    Really? That's all? I stand corrected!
    Last edited by ross1; 07-23-2012 at 10:52 AM. Reason: Automerged Doublepost

  18. #18
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    That sounds like too little!


    Ahhhhhhhh

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    Quote Originally Posted by 5mall5nail5 View Post
    That sounds like too little!


    Ahhhhhhhh
    Taking them OFF twenty years hence certainly requires significantly more effort.

  20. #20
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    Yes but I mean as fasteners go, the subframes are like M12 or M14... 57 ft lb sounds too little.

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    Quote Originally Posted by 5mall5nail5 View Post
    Yes but I mean as fasteners go, the subframes are like M12 or M14... 57 ft lb sounds too little.
    Indeed. LB/BG is my spec for large fasteners, never failed yet.

    EDIT; Just looked in Bentley which indicates 57 ft/lb for TRAILING ARM to subframe gr.10.9 bolts, those are M10 if I recall. Can't find a spec for subframe bush
    Last edited by ross1; 07-23-2012 at 11:16 AM.

  22. #22
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    If you can't find the right torque, BMW gives you a handy dandy chart with fastener sizes and thread types with suggested torques in their manual. That should get you close to what it should be. Nothing on my car has fallen off yet from the torques I used


    Drivertain: Getrag 260/6, E34 M5 clutch, 15 lb FW, E36 M3 shifter, Portland Driveline driveshaft
    Suspension: Eibach springs, Koni adjustable shocks/struts, M5 antiroll bars front/rear, M5 thrust arm bushings, fully rebuilt suspension/steering
    Engine: Rebuilt top end and resealed. Turner Motorsport ECU chip.
    Lighting: Euro smilies w/ 5500k HID lights, clear front corner lights

  23. #23
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    Quote Originally Posted by 5mall5nail5 View Post
    If you use a torque stick, what torque stick are you using?

    I don't like the "hit it with an impact gun" because I run my impact at 120 psi and it produces like 250 ft lb....
    Our shop air is at a little more than that so you will be fine. You could of had the whole subframe in by now. I understand you wanting to go by the book but it's not that big of a deal on a bolt like this.

  24. #24
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    Quote Originally Posted by EuroPartConnect View Post
    Our shop air is at a little more than that so you will be fine. You could of had the whole subframe in by now. I understand you wanting to go by the book but it's not that big of a deal on a bolt like this.
    I am not stalling for tq measurements. I am waiting on orders of fasteners to come in. Its not air pressure that dictates torque. The gun and and the line size do too. There are some torque wrenches that are 400 ft lbs at 125 psi..

    I will measure the bolts and look up the torque specs equiv based on material type

  25. #25
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    These are M14x1.5 bolts, probably grade 8.8.

    Here is the page that says that the proper torque spec. is 140 Nm (line 3AZ below):



    Here is the torque table:


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