Author Topic: Need advice about welding leaf spring perches.  (Read 11355 times)

Offline team39763

  • Senior Member
  • ****
  • Posts: 1194
Need advice about welding leaf spring perches.
« on: May 01, 2011, 01:39:21 am »
I bought the Mopar 2.5" leafspring perches.  I noticed on the old flipkit brackets they had an offset pin hole to keep things spaced the same as stock.  My new perches have a large center hole aswell as a square hole on one side of it and a small round hole on the other side.  Am I supposed to be using that center hole on the perches or the offset hole?  I'll post a pic if needed.

Offline VileZambonie

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 19170
Re: Need advice about welding leaf spring perches.
« Reply #1 on: May 01, 2011, 09:21:05 am »
Umm... What are you welding the perches to? Are you building a custom rear end? Maybe you should locate them on the spring and move the axle in at ride height, set the pinion angle and tack them in place. If it's a stock rear end why are you even messing with it and why Mopar perches?
,                           ___ 
                         /  _ _ _\_
              ⌠¯¯¯¯¯'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline big bear

  • Junior Member
  • ***
  • Posts: 681
Re: Need advice about welding leaf spring perches.
« Reply #2 on: May 01, 2011, 09:31:48 am »
i was curious about why your running mopar perches also?

Offline Irish_Alley

  • Tim
  • Senior Member
  • ****
  • Posts: 13333
  • Family is not an important thing. It's everything.
Re: Need advice about welding leaf spring perches.
« Reply #3 on: May 01, 2011, 10:21:00 am »
They are kind of generic perches. When i got some for an axle that’s the ones i got but i can’t remember what type of holes or anything they had
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline team39763

  • Senior Member
  • ****
  • Posts: 1194
Re: Need advice about welding leaf spring perches.
« Reply #4 on: May 01, 2011, 02:15:57 pm »
They look like my stock ones, just thicker and they came in a Mopar box.

I'm welding the perches to the rearend.  It's a stock rearend with spring perches on the top and I want the spring perches on the bottom.  I'm planning to do it very similar to how Lorne set up his rearend.  I'll tackle it just as you said vile, locate it on the springs, set the pinion angle, then tack in place.

Offline bake74

  • Senior Member
  • ****
  • Posts: 5871
    • Build Thread
Re: Need advice about welding leaf spring perches.
« Reply #5 on: May 01, 2011, 03:37:57 pm »
     The large center hole is the one you use, remember to have the weight of the truck on the springs before you tack them to get the right pinion angle.
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
  74 k10, 77k10    Tom

Offline HAULIN IT

  • Senior Member
  • ****
  • Posts: 1542
Re: Need advice about welding leaf spring perches.
« Reply #6 on: May 03, 2011, 06:50:51 pm »
Team, The reason for the hole being off-set in your flipkit was because of the axle going foreward when you move it to the top of the springs (this is why I was concerned about Vile asking for a measurement from other guys trucks awhile back for the rearend centerline). If you use the center hole your wheelbase will be shorter by the amount between the axle centerline & the off-set hole in the flipkit bracket...about 5/8-3/4""? Not a big deal since both sides are still the same & the wheel opening is so big & isn't round. If it bothers you, drill a new hole/open up one of the smaller ones to fit your pin. There is nothing wrong with the hole not being in the center. Lorne   

Offline VileZambonie

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 19170
Re: Need advice about welding leaf spring perches.
« Reply #7 on: May 03, 2011, 09:07:06 pm »
Lorne,

I forgot about that thread. I found exact measurements based on reference points on the frame. You must have access to some body specifications for these trucks no? That helped me figure out exactly where I needed to measure off of.
,                           ___ 
                         /  _ _ _\_
              ⌠¯¯¯¯¯'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline HAULIN IT

  • Senior Member
  • ****
  • Posts: 1542
Re: Need advice about welding leaf spring perches.
« Reply #8 on: May 03, 2011, 10:55:27 pm »
Vile, Yes, I do...I have them stashed away somewhere. We wouldn't be fixing any of these trucks anymore at work, but I've kept/copied some of the pages "of interest". The last time I had them out, I had both the 2WD & 4x4 pages & was planning to convert a 2WD truck into a 4x4 with a friend. He had a real nice 3/4 ton 2WD, but wanted a 4x4...I had/have some parts laying around to do the deed, but he ended up selling the truck. The frame specs do come in handy at times for all sorts of things, glad to hear you got yours sorted out. Lorne 

Offline team39763

  • Senior Member
  • ****
  • Posts: 1194
Re: Need advice about welding leaf spring perches.
« Reply #9 on: May 04, 2011, 09:23:52 am »
I think my biggest concern is the driveshaft length.  When I bought the driveshaft I had the flipkit installed with the offset pin.

Offline Captkaos

  • OWNER and Administrator
  • Administrator
  • Senior Member
  • *****
  • Posts: 18454
    • http://www.73-87chevytrucks.com
Re: Need advice about welding leaf spring perches.
« Reply #10 on: June 30, 2011, 01:03:57 pm »
Lorne,
Care to share this info?

Offline HAULIN IT

  • Senior Member
  • ****
  • Posts: 1542
Re: Need advice about welding leaf spring perches.
« Reply #11 on: July 01, 2011, 12:04:05 am »
Chris, Would be glad to. I did locate a full set (2wd long & short, 4wd long & short, Blazer & Suburban) tonight. Most of them are from '84. The basics will be the same for all of the years, however there may be some slight differences in the years resulting in not every hole will match every year frame, ect. but it should be able to help many with a bit of checking "Do I have this hole in my frame or do I need to measure from here to here (from &/to a different hole or mount) that is the same on all of them?" One thing that I did find slightly amusing while getting them copied was the "discrepancies" from the different frames like across the front radiator support bushing mounts (we all know they are the same number based on rad supports being the same) however there is 1/4" difference in that measurement from 2wd long/short & Blazer or something like that. We have to remember that the tolerance in '84 was every bit 1/4"...3/8" would probably been a "good" frame repair back then.
Chris, Send me a PM of the mailing address where you would like them sent...I'm not very good with Computers, scanners, ect. & wouldn't know how to begin to do it electronically. Maybe you can figure a way to do something with them. They are rather long (18" I'd guess) so that may pose a problem. Lorne

Offline Captkaos

  • OWNER and Administrator
  • Administrator
  • Senior Member
  • *****
  • Posts: 18454
    • http://www.73-87chevytrucks.com
Re: Need advice about welding leaf spring perches.
« Reply #12 on: July 14, 2011, 09:59:33 am »
sent you a PM reply.