Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

stripped U-bolt - torque values?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by djohnsn, Apr 12, 2001.

  1. djohnsn

    djohnsn 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    327
    Likes Received:
    2
    Location:
    Plano, Texas
    What do ya'll use for a torque value for U-bolts on a front 10-bolt? The shop manual says 150, but I stripped out a new (ProComp) U-bolt at 150. (The bolt was new, threads cleaned on both the bolt and nut with brake cleaner and allowed to dry.) I am purchasing another set today and don't want to strip these out!

    DJ
    78 K5
     
  2. lasvegas

    lasvegas 1/2 ton status

    Joined:
    Feb 27, 2001
    Posts:
    122
    Likes Received:
    0
    Location:
    Las Vegas, Nevada
    My local spring shop told me 125 for either the bolts that came with my lift kit or the custom ones I ended up having them make for me. They also recommended that I use a "tall nut" (I do not know the correct name) which is just about two times as tall as the nuts that came with my lift kit (plus no nylock). They hold better according to the shop and are less likely to strip.
     
  3. BurbinOR

    BurbinOR 3/4 ton status

    Joined:
    Feb 17, 2000
    Posts:
    5,829
    Likes Received:
    0
    Location:
    Oregon
    Don't take this as gospel, but I remember being told to "re-torque them to 100 lbs" a few years ago after I had front springs installed.

    <font color=orange>'79 - 406 TPI -<font color=orange> K5#5 - <font color=blue>See it at---&gt;<A target="_blank" HREF=http://www.blazzinor.coloradok5.com>http://www.blazzinor.coloradok5.com</A>
     
  4. UseYourBlinker

    UseYourBlinker 1 ton status

    Joined:
    Jun 7, 2000
    Posts:
    11,117
    Likes Received:
    0
    Location:
    .
    Mine are torqued to 100 also...

    [​IMG]
    <A target="_blank" HREF=http://community.webshots.com/user/vwryda>http://community.webshots.com/user/vwryda</A>
     
  5. AZK5

    AZK5 1/2 ton status

    Joined:
    Feb 22, 2000
    Posts:
    448
    Likes Received:
    0
    Location:
    Chandler, AZ
    What shop manual were you using? My shop manual says 125 ft lbs. Are you sure you weren't looking at the Newton Meter (NM) number which the shop manual lists both.
    CB
     
  6. '73 K5

    '73 K5 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    1,763
    Likes Received:
    0
    Location:
    Kansas
    When I did my lift last year I torqued them down to 125...thats what the Superlift paperwork said and its worked out just fine so far.

    '73 K5
    Chevy good...Ford bad
     
  7. fad2blk99

    fad2blk99 1/2 ton status

    Joined:
    Feb 19, 2001
    Posts:
    860
    Likes Received:
    0
    Location:
    Charleston, SC
    I used Superlift. I was having similar problems. They verified that the torque value is indeed 150 ft/lb. The torque value depends on the diameter of the bolt. It sould be able to take 150 ft/lbs. This is also what the factory specifies for stock set up. Try using anti-seize compound. This will prevent gawling of the threads and give you a better torque.
     
  8. djohnsn

    djohnsn 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    327
    Likes Received:
    2
    Location:
    Plano, Texas
    I am using 1978 and 1984 factory shop manuals. The 125 ft lbs is for the rear, with 150 ft lbs for the front.

    Wouldn't using antiseize distort the torque readings?

    DJ
    78 K5
     
  9. Storm Trooper

    Storm Trooper 1/2 ton status GMOTM Winner

    Joined:
    Nov 24, 2000
    Posts:
    4,640
    Likes Received:
    1
    Location:
    Dillon Colorado, Hang'in in the mountains. Renting
    My Chiltons $hit manual said 150lbs. but I only went to 100.
    I figured I would run it for a while, then retorque.
    I don't belive any of them because the rear U-bolts are larger than the front and should have different spec.s (don't you)
    dump the crap u-bolts you have, they should still take 125.

    [​IMG]
     
  10. lasvegas

    lasvegas 1/2 ton status

    Joined:
    Feb 27, 2001
    Posts:
    122
    Likes Received:
    0
    Location:
    Las Vegas, Nevada
    using anti-sieze affects torque reading. Your shop manual should say something like "All torque values are dry unless otherwise specified". 150 pounds wet is not the same as 150 dry.
     
  11. Gopherkiller

    Gopherkiller 1/2 ton status

    Joined:
    Aug 14, 2000
    Posts:
    188
    Likes Received:
    0
    Hi Guys, Well I watched when using the "cheap" U bolts that the bolts them selfs will strecth. I'll never use them. I ALLWAYS use good U bolts, with the long nuts (more threads,) and put "antisieze" on the threads. I allways retourque them after a few miles. I never use a tourque wrench, just my BIG impact. If they are good bolts they will take it. GOPHERKILLER
     
  12. fad2blk99

    fad2blk99 1/2 ton status

    Joined:
    Feb 19, 2001
    Posts:
    860
    Likes Received:
    0
    Location:
    Charleston, SC
    As an aircraft mechanic, when ever we use high torque values antisieze is a must due to the friction the higher torque values create. Antisieze is a must for a true torque value on high torque aplications as the friction creates resistance and the resistance affects torque. I've seldom seen it used in automotive applications except in high heat areas such as spark plugs and exhaust components. You also SHOULDN'T need it on new hardware. This is all according to aircraft technical manuals. -Tommy
     
  13. FWP

    FWP CRS

    Joined:
    Oct 11, 2000
    Posts:
    3,845
    Likes Received:
    3
    Location:
    Prescott Valley, AZ
    Didn't they engineer that thought into the original torque value for the size bolt and torque amount????

    [​IMG]
     
  14. Pure Insanity

    Pure Insanity 1/2 ton status

    Joined:
    Mar 17, 2001
    Posts:
    4,579
    Likes Received:
    0
    Location:
    Dade City, Florida
    let me check my impact to see what the ft/lbs is.hehe!i run mine down till they quit turnin.never had a prob.

    PURE INSANITY
    86 blazer see it at:<A target="_blank" HREF=http://www.zing.com/album/pictures.html?id=4292792569>http://www.zing.com/album/pictures.html?id=4292792569</A>
     

Share This Page