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.

CV Shaft or reweld perches? Need some advice...

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by BlazerBoy, Feb 1, 2001.

  1. BlazerBoy

    BlazerBoy 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    639
    Likes Received:
    0
    Location:
    Chicago IL.
    Well last night I spit out a ujoint out of the yoke on the front side of the rear driveshaft. I have a 4" lift I know my angles are off a little, but I have already put 6 1/2 degrees of shim in there and I think I need a few more degrees. What is the best way to fix this?? should I take out the shims and change the angles on my perches, or get a new cv joint driveshaft? How much does a cv joint driveshaft cost?? where is the best place to get one?? Also how come it seems that other trucks dont have such severe angles with there 4" lift? I have lowered the transfer case an inch, I have 6 1/2 degrees of shim with a 4' shackle flip. and this set up almost cured the vibration but I still feel it.... any advise is welcomed thanks...

    BlazerBoy
    http://generalblueballs.coloradok5.com
     
  2. BurbinOR

    BurbinOR 3/4 ton status

    Joined:
    Feb 17, 2000
    Posts:
    5,829
    Likes Received:
    0
    Location:
    Oregon
    That is one of the best questions. I personally will/would go to a CV shaft, spend the money up front and forget about dicking around with angles and vibrations. Think drivelineman can supply those to us...........? Last I heard, cost was around $250 for a new CV style driveshaft.

    <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>
     
  3. Brian 89KBlazer

    Brian 89KBlazer 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    779
    Likes Received:
    0
    Location:
    Ontario, Canada
    CV shaft or not, you've still got to reweld perches. If you want to a fix to remove the shims, you'll have to reweld and if you go to a CV shaft, you need to rotate the rear pinion to approx. 1-2 degrees below straight in line with the rear driveshaft. That's the route I'm going and I'd recommend. Like BlazzinOR said, it's a few bucks more up front but its a permanent fix.

    Good Luck
    Brian
    89KBlazer
     
  4. californiak5

    californiak5 1/2 ton status

    Joined:
    Oct 25, 2000
    Posts:
    820
    Likes Received:
    0
    Location:
    Oceanside, Ca. 92056
    I believe that he said that he had a 4" Shackle Flip on the truck. If that is the case he could most likely raise the T-case back up and remove the shims and the angle of the pinion should be about right for a C/V shaft. At least it was for my K5, others could be different.

    [​IMG] Born to Drive My K5 [​IMG]
     
  5. BlazerBoy

    BlazerBoy 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    639
    Likes Received:
    0
    Location:
    Chicago IL.
    yeah that is about that it looks like... If I take out the shiims it comes pretty close to where it should be for a cv shaft?? How much do these driveshafts cost...

    BlazerBoy
    http://generalblueballs.coloradok5.com
     
  6. tom

    tom 1/2 ton status

    Joined:
    May 20, 2000
    Posts:
    157
    Likes Received:
    0
    Location:
    So. Cal
    Boy am I confused. I thought the CV joint would go at the T-case end and the pinion should be raised (rotated) up to be nearly in line with the driveshaft. That way the CV takes the big angle at the t-case and since it is Constant Velocity it doesn't vibrate. The angle at the pinion is nesr zero so it doesn't vibtrate either. If this approach is right, then wouldn't you have to either reweld the perches or put in 10-14 degrees of shim? BTW, how much angle can a 1350 type joint take?
     
  7. Brian 89KBlazer

    Brian 89KBlazer 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    779
    Likes Received:
    0
    Location:
    Ontario, Canada
    Tom

    You've pretty much summed it up! I just neglected to read carefully before replying and missed the fact that he had a shackle flip already installed. [​IMG] If he didn't have the flip, then the axle (& pinion) would have to be rotated up to line up with the driveshaft (within 1-2 degrees below in line for axlewrap) using either shims or rewelded spring pads.

    Brian
    89KBlazer

    <P ID="edit"><FONT SIZE=-1>Edited by Brian 89KBlazer on 02/01/01 12:18 PM (server time).</FONT></P>
     
  8. BurbinOR

    BurbinOR 3/4 ton status

    Joined:
    Feb 17, 2000
    Posts:
    5,829
    Likes Received:
    0
    Location:
    Oregon
    Thanks for the clarification. Sounds like a CV joint is not the "end all do all" solution I had in mind. My goal was not having to tip the pinion angle up at all............sounds like double work to me. Might be a good solution to vibrations if there is no other solution.

    <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>
     
  9. bigblue

    bigblue 1/2 ton status

    Joined:
    Dec 6, 2000
    Posts:
    658
    Likes Received:
    0
    Location:
    southern california
    I just got the CV conversion and 6 inch lift. Dropping he T-case did wonders but I know the angle still is making the U joint unhappy. My goal was also not to have to drop the T-case, but I had to. good luck

    baja surf nazi
     
  10. Executioner

    Executioner 1/2 ton status

    Joined:
    Feb 22, 2000
    Posts:
    1,530
    Likes Received:
    0
    Location:
    Temp. Ft. Walton Beach Fl. home=Tucson, Az.
    Um, I think you are missing something here. You need to find out why(the root cause) the u-joint failed.
    My guess is your driveshaft may be on the short side, have you considered this ?
    Vibrations in the drivetrain can loosen(cause wear) up pinion bearings, both u-joints, and even cause damage to
    splines.
    Good luck
     
  11. BlazerBoy

    BlazerBoy 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    639
    Likes Received:
    0
    Location:
    Chicago IL.
    How do I determine if my drive shaft is too short??
    I mean I imagine it is because it is lifted with the stock shaft. But I know plenty of people with 4" lift and the stock shaft??? Also what are the strongest ujoints for my stock shaft?? I think you guys talk about spicer 1510 or something?? Where do I get these ujoints???

    BlazerBoy
    http://generalblueballs.coloradok5.com
     
  12. Overdrive

    Overdrive Registered Member

    Joined:
    Feb 28, 2000
    Posts:
    93
    Likes Received:
    0
    Location:
    Gilbert, Arizona
    I just went through the CV joint conversion (CV and proper total length). Mesa Driveshaft here in Mesa Arizona was great. Cost me $350 but it was worth it. I have a 77 K5' 4" springs all the way around. The replacement rear springs had small shims attached. Also droped the T-case. The CV took care of most of the vibration problems. I checked the driveshaft angle with an angle finder before the conversion and it was just at 15 degrees. I have no plans for anything further, like repositioning the spring mounts. I think the best thing to do after all I have done is just keep the u-joints lubed ever couple of months, always have a spare u-joint in the truck, and I am DEFINATELY fabricating a drive shaft loop to hold the sucker if it ever breaks again! One word of extreme CAUTION... do NOT put "heavy duty" u-joints in to replace the stock ones. Reason: it is better to break a joint on the trail than to destroy a yoke.... I have done this several times. Hope this helps.

    And as I have posted before, if you have a 203 t-case you can travel 205 miles on just the front driveshaft, in the middle of Thanksgiving night, driving at 45 miles per hour....

    Overdrive
     

Share This Page